Bio-Medical Materials and Engineering - Volume 35, issue 3

Authors: Murugan, Shunmuga Priyan | George, Godwin | Jaisingh, Julyes

Article Type: Research Article

Abstract: BACKGROUND: This investigation was conducted to encapsulate 316L SS with a Ti-based alloy coating. OBJECTIVE: The aim was to fabricate a coating using TiN, TiO2 , and TiCoCr powders on 316L SS through the physical vapor deposition (PVD) sputtering process. METHODS: The powders were consecutively coated on 316L SS through the PVD sputtering process with coating durations of 30, 60, and 90 min. Further microhardness, surface roughness, microabrasion, and adhesion strength tests were also carried out. RESULTS: A 60% improvement in abrasion resistance was observed in TiCoCr-coated samples compared to the uncoated substrate. The …X-ray diffraction results confirmed the optimal formation of Ti alloy coatings with corresponding orientation over the SS substrates. Moreover, TiCoCr with a 90 min coating duration had much better surface characteristics than TiO2 and TiN. CONCLUSION: The 90 min coating duration should be optimal for coating in steel for bio-implants. Show more

Keywords: Roughness, micro-abrasion, microhardness, adhesion

DOI: 10.3233/BME-230127

Citation: Bio-Medical Materials and Engineering, vol. 35, no. 3, pp. 219-235, 2024

Authors: He, Fan | Li, Minru | Hua, Lu | Guo, Tingting

Article Type: Research Article

Abstract: BACKGROUND: The incidence of arterial stenosis is increasing year by year. In order to better diagnose and treat arterial stenosis, numerical simulation technology has become a popular method. OBJECTIVE: A novel model is constructed to investigate the influence of microcirculation on the hemodynamics of artery bypass graft. METHODS: In this paper, a severely narrow artery bypass graft model is considered. The geometric shape includes a narrow artery tube and a bypass graft of the same diameter with a 45° suture angle. The fluid-structure interaction model is considered by finite element numerical calculation, and the flow is …simulated with microcirculation as the outlet boundary condition. The changes of blood flow velocity, pressure and wall shear stress are analyzed. RESULTS: The results show that blood almost entirely flows into the graft tube and there is no recirculation area at the anastomosis. CONCLUSION: The artery bypass graft model considering microcirculation function could simulate the physiological characteristics of blood flow more reasonably, and it provide helps for clinicians to diagnose and treat arterial stenosis. Show more

Keywords: Stenosis, microcirculation, artery bypass graft, hemodynamics, fluid-structure interaction

DOI: 10.3233/BME-230145

Citation: Bio-Medical Materials and Engineering, vol. 35, no. 3, pp. 237-248, 2024

Authors: Tan, Poh Ling | Kanesan, Jeevan | Chuah, Joon Huang | Badruddin, Irfan Anjum | Abdellatif, Abdallah | Kamangar, Sarfaraz | Hussien, Mohamed | Ali Baig, Maughal Ahmed | Ameer Ahammad, N.

Article Type: Research Article

Abstract: BACKGROUND: The scientific revolution in the treatment of many illnesses has been significantly aided by stem cells. This paper presents an optimal control on a mathematical model of chemotherapy and stem cell therapy for cancer treatment. OBJECTIVE: To develop effective hybrid techniques that combine the optimal control theory (OCT) with the evolutionary algorithm and multi-objective swarm algorithm. The developed technique is aimed to reduce the number of cancerous cells while utilizing the minimum necessary chemotherapy medications and minimizing toxicity to protect patients’ health. METHODS: Two hybrid techniques are proposed in this paper. Both techniques combined OCT …with the evolutionary algorithm and multi-objective swarm algorithm which included MOEA/D, MOPSO, SPEA II and PESA II. This study evaluates the performance of two hybrid techniques in terms of reducing cancer cells and drug concentrations, as well as computational time consumption. RESULTS: In both techniques, MOEA/D emerges as the most effective algorithm due to its superior capability in minimizing tumour size and cancer drug concentration. CONCLUSION: This study highlights the importance of integrating OCT and evolutionary algorithms as a robust approach for optimizing cancer chemotherapy treatment. Show more

Keywords: Hybrid optimal control, particle swarm optimization, evolutionary algorithms, constrained optimization, multi-objective optimization

DOI: 10.3233/BME-230150

Citation: Bio-Medical Materials and Engineering, vol. 35, no. 3, pp. 249-264, 2024

Authors: Tian, Yongzheng | Sun, Ruilong | Li, Yunfei | Liu, Peng | Fan, Bo | Xue, Yun

Article Type: Review Article

Abstract: BACKGROUND: Bone defects arising from diverse causes, such as traffic accidents, contemporary weapon usage, and bone-related disorders, present significant challenges in clinical treatment. Prolonged treatment cycles for bone defects can result in complications, impacting patients’ overall quality of life. Efficient and timely repair of bone defects is thus a critical concern in clinical practice. OBJECTIVE: This study aims to assess the scientific progress and achievements of magnesium phosphate bone cement (MPC) as an artificial bone substitute material. Additionally, the research seeks to explore the future development path and clinical potential of MPC bone cement in addressing challenges associated …with bone defects. METHODS: The study comprehensively reviews MPC’s performance, encompassing e.g. mechanical properties, biocompatibility, porosity, adhesion and injectability. Various modifiers are also considered to broaden MPC’s applications in bone tissue engineering, emphasizing drug-loading performance and antibacterial capabilities, which meet clinical diversification requirements. RESULTS: In comparison to alternatives such as autogenous bone transplantation, allograft, polymethyl methacrylate (PMMA), and calcium phosphate cement (CPC), MPC emerges as a promising solution for bone defects. It addresses limitations associated with these alternatives, such as immunological rejection and long-term harm to patients. MPC can control heat release during the curing process, exhibits superior mechanical strength, and has the capacity to stimulate new bone growth. CONCLUSION: MPC stands out as an artificial bone substitute with appropriate mechanical strength, rapid degradation, non-toxicity, and good biocompatibility, facilitating bone repair and regeneration. Modification agents can enhance its clinical versatility. Future research should delve into its mechanical properties and formulations, expanding clinical applications to create higher-performing and more medically valuable alternatives in bone defect repair. Show more

Keywords: Biomaterials, bone regeneration, magnesium phosphate cement, bone cement, strength of materials

DOI: 10.3233/BME-230164

Citation: Bio-Medical Materials and Engineering, vol. 35, no. 3, pp. 265-278, 2024

Authors: Liu, Xiaojiang | Guo, Zongfeng | Li, Jun | Wu, Demo | Liu, Zhongping | Guan, Cheng | Guan, Yixiang | Lu, Xiaomin

Article Type: Research Article

Abstract: BACKGROUND:  Glioblastoma is the most aggressive brain tumor with poor prognosis. Although Resveratrol (Rsv) is known to have therapeutic effects on glioma, the effects of gold-conjugated resveratrol nanoparticles (Rsv-AuNPs) on glioma cells are rarely reported. OBJECTIVE: We aimed to investigate the effects of Rsv-AuNPs on glioma cells and its underlying mechanism. METHOD: Human glioma cell line U87 was treated with different concentrations of Rsv-AuNPs. CCK-8, transwell, and wound healing assay were performed to measure the effects of Rsv-AuNPs on cell proliferation, invasion, and migration ability, respectively. Flow cytometry assay was used to detect the effects of …Rsv-AuNPs on apoptosis. Changes of protein expressions related to proliferation, invasion, migration, and apoptosis were measured by Western blot assay. In addition, the inhibitory role of Rsv-AuNPs in the PI3K/AKT/mTOR signaling pathway was verified by using PI3K inhibitor LY294002.  RESULTS: Rsv-AuNPs treatment significantly suppressed proliferation, migration, and invasion of U87 cells (all P < 0.05) and increased the apoptosis rate (P < 0.05). The changes of proteins related to proliferation, migration, invasion and apoptosis were consistent (all P < 0.05). Moreover, Rsv-AuNPs treatment significantly inhibited the phosphorylation of PI3K, AKT and mTOR proteins in U87 cells (P < 0.05). CONCLUSION: The present study found that Rsv-AuNPs inhibited the proliferation, migration, and invasion of U87 cells and induced apoptosis by inhibiting the activation of PI3K/AKT/mTOR signaling pathway. In the future, Rsv-AuNPs might be applied to the clinical treatment of glioma through more in-depth animal and clinical research. Show more

Keywords: Gold-conjugated resveratrol nanoparticles, glioma cell, mechanism

DOI: 10.3233/BME-230171

Citation: Bio-Medical Materials and Engineering, vol. 35, no. 3, pp. 279-292, 2024

Authors: Sakoda, Hideyuki | Tsuboko, Yusuke | Okamoto, Yoshihiro | Yamamoto, Eiichi | Imagama, Takashi | Sakai, Takashi | Hamada, Hidetoshi | Sugano, Nobuhiko

Article Type: Research Article

Abstract: BACKGROUND: The ultra-high molecular weight polyethylene (UHMWPE) component of artificial joints is one of the most important factors affecting the clinical outcomes of joint arthroplasty. Although the possibility of in vivo UHMWPE degradation caused by absorbed lipids has been reported, a quantitative evaluation of this phenomenon has not yet been performed. OBJECTIVE: This study aimed to establish the lipid index (LI) as a quantitative indicator of the amount of absorbed lipids and the first step to quantify their effects on UHMWPE. METHODS: The LI was defined using the infrared spectrum obtained with a Fourier-transform infrared …spectrophotometer and verified using the retrieved UHMWPE components. RESULTS: The LI was consistent with the amount of extract recovered in reflux extraction with hexane. In addition, the LI could replace lipid extraction for calculating the oxidation index (OI) because the value obtained by subtracting the LI from the OI showed good agreement with the OI obtained after lipid extraction. CONCLUSION: The LI represents the amount of lipids absorbed by UHMWPE and is useful for quantitatively evaluating the effects of lipids on UHMWPE. In addition, the LI enables OI measurements that are unaffected by absorbed lipids without requiring troublesome lipid-extraction procedures. Show more

Keywords: Peak separation, FTIR, retrieval study, UHMWPE component, oxidation index

DOI: 10.3233/BME-230183

Citation: Bio-Medical Materials and Engineering, vol. 35, no. 3, pp. 293-302, 2024

Authors: Wang, Binyu | Zang, Lianru | Lu, Yingxi | Zhan, Mengying | Sun, Tingting | Zhou, Yu | Song, Chengli

Article Type: Research Article

Abstract: BACKGROUND: The clinical outcomes of bipolar radiofrequency (RF) lipolysis, a prevalent non-invasive fat reduction procedure, hinge on the delicate balance between effective lipolysis and patient safety, with skin overheating and subsequent tissue damage as primary concerns. OBJECTIVE: This study aimed to investigate a novel bipolar radiofrequency lipolysis technique, safeguarding the skin through an innovative PID temperature control algorithm. METHODS: Utilizing COMSOL Multiphysics simulation software, a two-dimensional fat and skin tissue model was established, simulating various PID temperature control schemes. The crux of the simulation involved a comparative analysis of different PID temperatures at 45 °C, 50 …°C, and 55 °C and constant power strategies, assessing their implications on skin temperature. Concurrently, a custom bipolar radiofrequency lipolysis device was developed, with ex vivo experiments conducted using porcine tissue for empirical validation. RESULTS: The findings indicated that with PID settings of K p = 7, K i = 2, and K d = 0, and skin temperature control at 45 °C or 50 °C, the innovative PID-based epidermal temperature control strategy successfully maintained the epidermal temperature within a safe range. This maintenance was achieved without compromising the effectiveness of RF lipolysis, significantly reducing the risk of thermal damage to the skin layers. CONCLUSION: Our research confirms the substantial practical utility of this advanced PID-based bipolar RF lipolysis technique in clinical aesthetic procedures, enhancing patient safety during adipose tissue ablation therapies. Show more

Keywords: Bipolar radiofrequency lipolysis, PID temperature control algorithm, simulation calculations, skin overheating, thermal damage

DOI: 10.3233/BME-230185

Citation: Bio-Medical Materials and Engineering, vol. 35, no. 3, pp. 303-321, 2024

Authors: Mukasheva, Fariza | Zhanbassynova, Ainur | Erisken, Cevat

Article Type: Research Article

Abstract: BACKGROUND: The ligament is the soft tissue that connects bone to bone and, in case of severe injury or rupture, it cannot heal itself mainly because of its poor vascularity and dynamic nature. Tissue engineering carries the potential to restore the injured tissue functions by utilization of scaffolds mimicking the structure of native ligament. Collagen fibrils in the anterior cruciate ligament (ACL) have a diameter ranging from 20 to 300 nm, which defines the physical and mechanical properties of the tissue. Also, the ACL tissue exhibited a bimodal distribution of collagen fibrils. Currently, the ability to fabricate scaffolds replicating this structure …is a significant challenge. OBJECTIVE: This work aims at i) measuring the diameter of collagens of bovine ACL tissue, ii) investigating the fabrication of sub-100 nm fibers, and iii) fabricating aligned scaffolds with bimodal diameter distribution (with two peaks) resembling the healthy ACL structure. It is hypothesized that such scaffolds can be produced by electrospinning polycaprolactone (PCL) solutions. METHODS: To test the hypothesis, various PCL solutions were formulated in acetone and formic acid in combination with pyridine, and electrospun to generate sub-100 nm fibers. Next, this formulation was adjusted to produce nanofibers with a diameter between 100 nm and 200 nm. Finally, these solutions were combined in the co-electrospinning process, i.e., two-spinneret electrospinning, to fabricate biomimetic scaffolds with a bimodal distribution. RESULTS: Electrospinning of 8% and 15% PCL solutions, respectively, resulted in the production of fibers with diameters below and above 100 nm. The combined scaffold exhibited a bimodal distribution of aligned fibers with peaks around 80 and 180 nm, thus mimicking the collagen fibrils of healthy ACL tissue. CONCLUSION: This research is expected to have a society-wide impact because it aims to enhance the health condition and life quality of a wide range of patients. Show more

Keywords: Ligament, polycaprolactone, electrospinning, fiber diameter distribution, bimodal

DOI: 10.3233/BME-230193

Citation: Bio-Medical Materials and Engineering, vol. 35, no. 3, pp. 323-335, 2024