Bio-Medical Materials and Engineering - Volume 33, issue 1

Authors: Hirota, Masatsugu | Hayakawa, Tohru

Article Type: Research Article

Abstract: BACKGROUND: The adsorption of salivary pellicle proteins onto the material surface is key for denture plaque formation. OBJECTIVE: We aimed to investigate the adsorption of bovine serum albumin (BSA) and mucin (MCN) onto denture base metal materials using a 27-MHz quartz crystal microbalance (QCM) method. METHODS: A gold (Au), titanium (Ti), and cobalt chromium alloy (Co–Cr) sensors were employed for QCM measurements. Adsorbed amounts of BSA or MCN were calculated by observing the frequency decrease, and the apparent reaction rate, k obs , was obtained by the curve fitting of the frequency shift against the …adsorption time. RESULTS: The adsorbed amounts of BSA on Ti were significantly lower than those on Au and Co–Cr. For MCN adsorption, Au showed significantly greater amounts of adsorption than Co–Cr. The k obs of Ti for BSA adsorption was significantly smaller than for the Co–Cr. The k obs of Ti, and Co–Cr for MCN adsorption were significantly smaller than for the Au. A clear correlation was not determined between adsorbed amounts of BSA or MCN onto each sensor and the surface topography or contact angles. CONCLUSIONS: The difference of denture base metals and the difference of salivary proteins influences the adsorption behavior of salivary proteins. Show more

Keywords: QCM, salivary protein, bovine serum albumin, mucin, denture plaque, denture base metal

DOI: 10.3233/BME-206013

Citation: Bio-Medical Materials and Engineering, vol. 33, no. 1, pp. 1-11, 2022

Authors: Athani, Abdulgaphur | Ghazali, Nik Nazri Nik | Badruddin, Irfan Anjum | Kamangar, Sarfaraz | Anqi, Ali E. | Algahtani, Ali

Article Type: Research Article

Abstract: BACKGROUND: The blood flow in the human artery has been a subject of sincere interest due to its prime importance linked with human health. The hemodynamic study has revealed an essential aspect of blood flow that eventually proved to be paramount to make a correct decision to treat patients suffering from cardiac disease. OBJECTIVE: The current study aims to elucidate the two-way fluid-structure interaction (FSI) analysis of the blood flow and the effect of stenosis on hemodynamic parameters. METHODS: A patient-specific 3D model of the left coronary artery was constructed based on computed tomography (CT) images. …The blood is assumed to be incompressible, homogenous, and behaves as Non-Newtonian, while the artery is considered as a nonlinear elastic, anisotropic, and incompressible material. Pulsatile flow conditions were applied at the boundary. Two-way coupled FSI modeling approach was used between fluid and solid domain. The hemodynamic parameters such as the pressure, velocity streamline, and wall shear stress were analyzed in the fluid domain and the solid domain deformation. RESULTS: The simulated results reveal that pressure drop exists in the vicinity of stenosis and a recirculation region after the stenosis. It was noted that stenosis leads to high wall stress. The results also demonstrate an overestimation of wall shear stress and velocity in the rigid wall CFD model compared to the FSI model. Show more

Keywords: Left coronary artery, image processing, CFD, FSI, blood flow modeling

DOI: 10.3233/BME-201171

Citation: Bio-Medical Materials and Engineering, vol. 33, no. 1, pp. 13-30, 2022

Authors: Miyachi, Ryo | Koike, Nana | Kodama, Suzu | Miyazaki, Junya

Article Type: Research Article

Abstract: BACKGROUND: Although trunk muscles are involved in many important functions, evaluating trunk muscle strength is not an easy task. If trunk muscle mass and thickness could be used as indicators of trunk muscle strength, the burden of measurement would be reduced, but the relationship between trunk muscle strength and trunk muscle mass and thickness has not been clarified. OBJECTIVE: The purpose of this study was to clarify the relationship between trunk muscle strength and trunk muscle mass by bioelectrical impedance analysis and trunk muscle thickness by ultrasound imaging in healthy adults. METHODS: One hundred and twenty-one …healthy university students were included in this study. Trunk flexion/extension muscle strength and trunk muscle mass by bioelectrical impedance analysis, and trunk muscle thickness by ultrasound imaging were measured. RESULTS: Both trunk flexion strength and trunk extension strength were significantly correlated with trunk muscle mass and oblique and rectus abdominis muscle thickness. Multiple regression analysis showed that trunk extension muscle strength had an independent relationship with trunk muscle mass. CONCLUSIONS: This study demonstrated that trunk muscle mass or trunk muscle thickness can be used as an alternative means for evaluating trunk muscle strength, making the evaluation of trunk muscles less burdensome. Show more

Keywords: Trunk muscle, muscle strength, bioelectrical impedance analysis, ultrasound imaging

DOI: 10.3233/BME-211218

Citation: Bio-Medical Materials and Engineering, vol. 33, no. 1, pp. 31-40, 2022

Authors: Mukai, Manabu | Uchida, Kentaro | Sugo, Ken | Nakasu, Masanori | Nakajima, Takehiko | Takata, Ken | Takaso, Masashi | Urabe, Ken

Article Type: Research Article

Abstract: BACKGROUND: Periprosthetic joint infection is a major complication of total joint arthroplasty, with treatment requiring a two-stage exchange procedure and 6 weeks of systemic antibiotics. However, depending on the infection site, intravenous delivery of antibiotics like vancomycin (VCM) can have poor tissue transferability, thus reducing their therapeutic effect. OBJECTIVE: This study demonstrates the 24-week in vivo release profile and antibacterial activity of VCM from calcium phosphate cement impregnated with VCM (CPC/VCM) and compares them with those from polymethylmethacrylate impregnated with VCM (PMMA/VCM). METHODS: Rats were implanted with the test specimens between the fascia and quadriceps. After …implantation for 24 weeks, the test specimens were removed and residual VCM was extracted to calculate the concentration of VCM released into rat tissues. We also examined the antibacterial activity of releasable VCM from the removed test specimens by placing them directly onto the surface of agar. RESULTS: CPC/VCM released greater concentrations of VCM for a longer period of time within the 24 weeks than PMMA/VCM. Moreover, CPC/VCM released 1.4 to 26.1-fold more VCM than PMMA/VCM. Using Staphylococcus aureus , antibacterial activity was logarithmically correlated with VCM concentration across the entire concentration range tested (12.5–800 μg/mL). While the area within which inhibition was observed—the inhibition zone—for both CPC/VCM and PMMA/VCM formed and gradually shrank with time after implantation, that for CPC/VCM was significantly larger than that for PMMA/VCM in each week after implantation. CONCLUSION: CPC/VCM releases greater amounts of VCM with antibacterial activity for longer periods of time than PMMA/VCM, suggesting that CPC is effective for facilitating the release of antibiotics for local action in patients with established postoperative infection. Show more

Keywords: Antibacterial activity, calcium phosphate cement, polymethylmethacrylate, vancomycin, in vivo

DOI: 10.3233/BME-211243

Citation: Bio-Medical Materials and Engineering, vol. 33, no. 1, pp. 41-50, 2022

Authors: Takahashi, Yuki | Sato, Takashi | Mochizuki, Tomoharu | Watanabe, Satoshi | Tanifuji, Osamu | Katsumi, Ryota | Endo, Naoto

Article Type: Research Article

Abstract: BACKGROUND: After total knee arthroplasty (TKA), the femur tends to be located posteriorly under weight-bearing (WB) conditions, and a paradoxical femoral anterior motion occurs, leading to joint instability. OBJECTIVE: We aimed to clarify factors which affect the postoperative femoral anteroposterior position relative to the tibia under WB conditions (A-P position) in medial pivot (MP) TKA. METHODS: Among 126 knees (81 women) with primary TKA using MP prosthesis for varus osteoarthritic knees, 70 knees had cruciate-retaining inserts (CR) with the reduced conformity and 56 knees had cruciate-substituting inserts (CS) with the full conformity. Using the three-dimensional (3D) …assessment system, the associations between the A-P position and the factors including pre- and postoperative lower extremity alignment, component positions, and posterior femoral condylar offset (PCO), were assessed regarding the type of inserts. RESULTS: Significant correlations were seen between the A-P position and posterior tibial slope (PTS), medial PCO, and lateral PCO. Regarding the difference between the two inserts, the PTS, medial PCO, and lateral PCO significantly correlated with the A-P position in the CR, but only the PTS correlated in the CS. CONCLUSIONS: The increased PTS and decreased PCO were the dominant factors for the A-P position in MP TKA. Show more

Keywords: Femoral anteroposterior position, three-dimensional lower extremity alignment assessment system, posterior tibial slope, posterior condylar offset, total knee arthroplasty

DOI: 10.3233/BME-211299

Citation: Bio-Medical Materials and Engineering, vol. 33, no. 1, pp. 51-64, 2022

Authors: Tang, Ruo-Fu | Zhou, Xiao-Zhong | Niu, Lie | Qi, Yi-Ying

Article Type: Research Article

Abstract: BACKGROUND: Cartilage tissue lacks the ability to heal. Cartilage tissue engineering using cell-free scaffolds has been increasingly used in recent years. OBJECTIVE: This study describes the use of a type I collagen scaffold combined with WNT5A plasmid to promote chondrocyte proliferation and differentiation in a rabbit osteochondral defect model. METHODS: Type I collagen was extracted and fabricated into a collagen scaffold. To improve gene transfection efficiency, a cationic chitosan derivative N,N,N-trimethyl chitosan chloride (TMC) vector was used. A solution of TMC/WNT5A complexes was adsorbed to the collagen scaffold to prepare a WNT5A scaffold. Osteochondral defects were …created in the femoral condyles of rabbits. The rabbits were divided into defect, scaffold, and scaffold with WNT5A groups. At 6 and 12 weeks after creation of the osteochondral defects, samples were collected from all groups for macroscopic observation and gene expression analysis. RESULTS: Samples from the defect group exhibited incomplete cartilage repair, while those from the scaffold and scaffold with WNT5A groups exhibited “preliminary cartilage” covering the defect. Cartilage regeneration was superior in the scaffold with WNT5A group compared to the scaffold group. Safranin O staining revealed more proteoglycans in the scaffold and scaffold with WNT5A groups compared to the defect group. The expression levels of aggrecan, collagen type II, and SOX9 genes were significantly higher in the scaffold with WNT5A group compared to the other two groups. CONCLUSIONS: Type I collagen scaffold showed effective adsorption and guided the three-dimensional arrangement of stem cells. WNT5A plasmid promoted cartilage repair by stimulating the expression of aggrecan, type II collagen, and SOX9 genes and proteins, as well as inhibiting cartilage hypertrophy. Show more

Keywords: Cartilage regeneration, type I collagen, in situ tissue engineering, WNT5A, in vivo study

DOI: 10.3233/BME-211277

Citation: Bio-Medical Materials and Engineering, vol. 33, no. 1, pp. 65-76, 2022

Authors: Chang, Yili | Zhang, Fubao | Liu, Feng | Shi, Lianshui | Zhang, Lin | Zhu, Hongshui

Article Type: Research Article

Abstract: BACKGROUND: Craniofacial soft-tissue defects mostly have an impact on the treatment of various oral diseases. Tissue expander is an important technique for tissue reconstruction, especially for soft tissues in reconstructive surgery. OBJECTIVE: This research aimed to develop a new self-swelling tissue expander, namely hydrogel, for soft tissue reconstruction in craniofacial region. METHODS: In vitro, the chemical and physical characteristics of hydrogel were evaluated by SEM, swelling rate, mechanical testing, EDS, and FT-IR. In vivo, the craniofacial implant model of SD rats were divided into group A as control, group B with hydrogels for 1 week expansion, …group C for 2 weeks and group D for 4 weeks (n = 5), and the effects were analyzed by HE staining, histological and radiographic evaluation. RESULTS: The in vitro results suggested that dry hydrogel possessed a uniform surface with micropores, the surface of post-swelling hydrogel formed three-dimensional meshwork. Within 24 hours, hydrogels expanded markedly, then slowed down. The mechanical property of hydrogels with longer expansion was better, whose main elements were carbon and oxygen. FT-IR also verified its molecular structure. In vivo, the wounds of rats recovered well, hydrogels could be removed as one whole piece with original shape and examined by radiographic evaluation, besides, the expanded skin and developed fibrous capsule formed surrounding hydrogels. CONCLUSION: The new expander was designed successfully with good chemical and physical characteristics, and could be applied in an animal model to help tissue reconstruction. Show more

Keywords: Tissue expander, biomaterials, rat, tissue reconstruction

DOI: 10.3233/BME-211224

Citation: Bio-Medical Materials and Engineering, vol. 33, no. 1, pp. 77-90, 2022