Bio-Medical Materials and Engineering - Volume 26, issue 1-2

Authors: Sugiyama, Tomoko | Uo, Motohiro | Wada, Takahiro | Hongo, Toshio | Omagari, Daisuke | Komiyama, Kazuo | Oikawa, Masakazu | Kusama, Mikio | Mori, Yoshiyuki

Article Type: Research Article

Abstract: Metal patch test is often used in clinical settings when metal-induced contact dermatitis is suspected. However, the transdermal permeation behavior of metal ions from the patch test remains unclear. Current patch tests using high concentrations of metal salt solutions have some side effects, e.g. acute skin reactions to high concentrations of metal salt. To resolve these, estimating metal ion transdermal permeation is wished. In this study, synchrotron radiation X-ray fluorescence (SR-XRF) and micro-focused particle-induced X-ray emission (micro-PIXE) were used to visualize the time-dependent Ni permeation in mouse skin. The cross-sectional diffusion of Ni was visualized in a time-dependent manner. …Our results indicate that maximum Ni permeation occurs after 24 h of patch treatment, and the permeated Ni content was high in the epidermis and spread into the dermis beyond the basal layer. This method may be useful to determine the appropriate solution concentration and duration of administration for the patch test. Show more

Keywords: Metal allergy, skin patch test, synchrotron radiation X-ray fluorescence analysis, particle-induced X-ray emission analysis, elemental distribution imaging

DOI: 10.3233/BME-151543

Citation: Bio-Medical Materials and Engineering, vol. 26, no. 1-2, pp. 1-8, 2015

Authors: Kokubun, Ryo | Wang, Wei | Zhu, Shengli | Xie, Guoqiang | Ichinose, Shizuko | Itoh, Soichiro | Takakuda, Kazuo

Article Type: Research Article

Abstract: Ti-based bulk metallic glasses are reported with high strength, low Young modulus and high corrosion resistance, suggesting their potentials in biomedical applications. However a thorough in vivo evaluation of its biocompatibilities has not been conducted yet. In this study, we implanted bars of Ti-based bulk metallic glass in the femoral bone of rats, followed up local tissue reaction as well as its component ions’ diffusion in local area and whole body. The Ti-based BMG (Ti40 Zr10 Cu34 Pd14 Sn2 ) alloy exhibited favorable features of both high strength and high elasticity. In vivo implant evaluation showed that it …has a good tissue compatibility, equivalent bone integration and bonding ability with Ti sample. No component ion diffusion was detected up to 3 months post implantation. The possibility and efficacy of its use for bone implant is confirmed. Thus further long term implant study is recommended. Show more

Keywords: Bulk metallic glass, Ti-based alloy, in vivo

DOI: 10.3233/BME-151546

Citation: Bio-Medical Materials and Engineering, vol. 26, no. 1-2, pp. 9-17, 2015

Authors: Wang, Xiaotong | Ma, Bing | Chang, Jiang

Article Type: Research Article

Abstract: BACKGROUND: Vascular extracellular matrices (vECMs) have shown potential for small-diameter blood vessel tissue engineering applications. However, problems such as chemical instability and easy calcification are still remained. Chemical crosslinking using crosslinkers such as glutaraldehyde (GA) can improve mechanical properties and proteolysis resistance of vECMs, but leads to calcification and cytotoxicity. Procyanidins (PC) can crosslink ECMs with anti-calcification property and cytocompatibility, but the mechanical properties and chemical stability are unsatisfactory. OBJECTIVE: A novel co-crosslinking technique using PC and GA was developed, which combines the advantages of both PC and GA for enhancing mechanical properties and stability of vECMs …with reduced calcification and cytotoxicity. METHODS: Fresh carotid were decellularized and then crosslinked by PC and subsequent GA for 6 h respectively. The mechanical properties, dynamic release of PC, enzymatic degradation, calcification and cytotoxicity of crosslinked samples were evaluated. RESULTS: The co-crosslinked vECMs showed enhanced tensile strength, chemical and biological stability, comparable anti-calcification property as compared to pure PC-crosslinked samples. Cytotoxicity assay showed that the co-crosslinked vECMs were cytocompatible for supporting the adhesion and proliferation of HUVECs. CONCLUSIONS: Co-crosslinking with PC and GA might be a useful method for preparation of vECM scaffolds with potential applications in small-diameter blood vessel tissue engineering. Show more

Keywords: Vascular extracellular matrix (vECM), co-crosslinking, procyanidins, glutaraldehyde

DOI: 10.3233/BME-151548

Citation: Bio-Medical Materials and Engineering, vol. 26, no. 1-2, pp. 19-30, 2015

Authors: Tesavibul, Passakorn | Chantaweroad, Surapol | Laohaprapanon, Apinya | Channasanon, Somruethai | Uppanan, Paweena | Tanodekaew, Siriporn | Chalermkarnnon, Prasert | Sitthiseripratip, Kriskrai

Article Type: Research Article

Abstract: The fabrication of hydroxyapatite scaffolds for bone tissue engineering applications by using lithography-based additive manufacturing techniques has been introduced due to the abilities to control porous structures with suitable resolutions. In this research, the use of hydroxyapatite cellular structures, which are processed by lithography-based additive manufacturing machine, as a bone tissue engineering scaffold was investigated. The utilization of digital light processing system for additive manufacturing machine in laboratory scale was performed in order to fabricate the hydroxyapatite scaffold, of which biocompatibilities were eventually evaluated by direct contact and cell-culturing tests. In addition, the density and compressive strength of the scaffolds …were also characterized. The results show that the hydroxyapatite scaffold at 77% of porosity with 91% of theoretical density and 0.36 MPa of the compressive strength are able to be processed. In comparison with a conventionally sintered hydroxyapatite, the scaffold did not present any cytotoxic signs while the viability of cells at 95.1% was reported. After 14 days of cell-culturing tests, the scaffold was able to be attached by pre-osteoblasts (MC3T3-E1) leading to cell proliferation and differentiation. The hydroxyapatite scaffold for bone tissue engineering was able to be processed by the lithography-based additive manufacturing machine while the biocompatibilities were also confirmed. Show more

Keywords: Additive manufacturing, biocompatibility, tissue engineering, hydroxyapatite scaffolds

DOI: 10.3233/BME-151549

Citation: Bio-Medical Materials and Engineering, vol. 26, no. 1-2, pp. 31-38, 2015

Authors: Liu, Hengquan | Li, Junfeng | Zhou, Shijie | Long, Jiangping | Dong, Lihua | Wei, Guixiang

Article Type: Research Article

Abstract: Surface modification is one approach to enhance the biocompatibility of implanted cardiovascular devices. In this work, a copper-containing film used to blood contacted biomaterials was prepared by vacuum arc deposition. The phase composition of the films was investigated via X-ray diffraction, and the adherence strength of the films was evaluated with conventional deformation tests. Blood compatibility of the films was characterized by hemolysis ratio, clotting time and platelet adhesion etc. The surface of inferior vena cava filters were smooth and uniform, no cracks or delaminations were observed on the deformed surface. These results indicate that the mechanical behavior of the …films is suitable for withstanding deformation stresses as operation in clinic. Good blood compatibility of the copper-containing films was identified through experiment in vitro , the activated partial thromboplastin times (APTTs) of Cu/Ti films were similar to that of the uncoated substrate, and Cu/Ti films were also found to inhibit platelet adhesion comparing to the nitinol substrate. However, with increasing ratio of Cu/Ti, the hemolysis ratio increased, resulting in platelet damage. These results indicate that the copper-containing film has potential application on blood contacted devices. Show more

Keywords: Copper-containing film, mechanical behavior, blood compatibility

DOI: 10.3233/BME-151547

Citation: Bio-Medical Materials and Engineering, vol. 26, no. 1-2, pp. 39-47, 2015

Authors: Srinivas, M. | Basil, Tony | Mohan, C. Krishna

Article Type: Research Article

Abstract: Cardiovascular diseases (CVD) are a leading cause of unnecessary hospital admissions as well as fatalities placing an immense burden on the healthcare industry. A process to provide timely intervention can reduce the morbidity rate as well as control rising costs. Patients with cardiovascular diseases require quick intervention. Towards that end, automated detection of abnormal heartbeats captured by electronic cardiogram (ECG) signals is vital. While cardiologists can identify different heartbeat morphologies quite accurately among different patients, the manual evaluation is tedious and time consuming. In this chapter, we propose new features from the time and frequency domains and furthermore, feature normalization …techniques to reduce inter-patient and intra-patient variations in heartbeat cycles. Our results using the adaptive learning based classifier emulate those reported in existing literature and in most cases deliver improved performance, while eliminating the need for labeling of signals by domain experts. Show more

Keywords: Cardiovascular, classifier, electrocardiogram, ventricular ectopic beats, supra ventricular ectopic beats

DOI: 10.3233/BME-151552

Citation: Bio-Medical Materials and Engineering, vol. 26, no. 1-2, pp. 49-55, 2015

Authors: Hayashi-Sakai, Sachiko | Kondo, Tatsuya | Kasuga, Yuto | Sakamoto, Makoto | Endo, Hideaki | Sakai, Jun

Article Type: Research Article

Abstract: The purpose of the present study was to develop a novel-designed phantom that could be scanned with a sample in the same image, that specialize for quantitative analyses of human dentin mineral density using the X-ray attenuation method. A further attempt was made to demonstrate the intracoronal dentin mineral density using this phantom in mandibular incisors. The phantom prepared with a 15 mm hole in the center of an acrylic resin bar having an outside diameter of 25 mm and 8 small holes (diameter, 3 mm) were made at equal intervals around the center. Liquid dipotassium hydrogen phosphate (K2 HPO4 ) solutions were …established at 0.4, 0.6, 0.8 and 1.0 g/cm3 , and were arranged to these holes. The mean value of the intracoronal dentin mineral density was 1.486 ± 0.016 g/cm3 in the present study. As the results of the present study corresponded to previous reports, this new phantom was considered to be useful. This phantom enables the analysis of samples that are not readily available by conventional mechanical tests and may facilitate biomechanical investigations using X-ray images. It was suggested that this system is a simple, accurate and novel mineralization measuring system. Show more

Keywords: Mineral density, phantom, design, teeth, dentin

DOI: 10.3233/BME-151545

Citation: Bio-Medical Materials and Engineering, vol. 26, no. 1-2, pp. 57-65, 2015

Authors: Anuradha, P. | Varma, N.K. Sapna | Balakrishnan, Avinash

Article Type: Research Article

Abstract: The present research was aimed at developing surface coatings on NiTi archwires capable of protection against nickel release and to investigate the stability, mechanical performance and prevention of nickel release of titanium sputter coated NiTi arch wires. Coated and uncoated specimens immersed in artificial saliva were subjected to critical evaluation of parameters such as surface analysis, mechanical testing, element release, friction coefficient and adhesion of the coating. Titanium coatings exhibited high reliability on exposure even for a prolonged period of 30 days in artificial saliva. The coatings were found to be relatively stable on linear scratch test with reduced frictional …coefficient compared to uncoated samples. Titanium sputtering adhered well with the Ni–Ti substrates at the molecular level, this was further confirmed by Inductive coupled plasma emission spectroscopy (ICPE) analysis which showed no dissolution of nickel in the artificial saliva. Titanium sputter coatings seem to be promising for nickel sensitive patients. The study confirmed the superior nature of the coating, evident as reduced surface roughness, friction coefficient, good adhesion and minimal hardness and elastic modulus variations in artificial saliva over a given time period. Show more

Keywords: NiTi alloy, Ni allergy, sputtering, titanium, nanoindentation

DOI: 10.3233/BME-151550

Citation: Bio-Medical Materials and Engineering, vol. 26, no. 1-2, pp. 67-77, 2015

Authors: Zhu, Zhengbin | Han, Hui | Zhu, Jinzhou | Zhang, Jing | Du, Run | Ni, Jingwei | Ying, Chen | An, Xuanqi | Zhang, Ruiyan

Article Type: Research Article

Abstract: BACKGROUND: Drug-eluting balloons (DEB) may be promising technology for treating atherosclerotic arterial disease. In fact, several DEBs have been clinically available for the treatment of coronary in-stent restenosis (ISR), de novo coronary lesions, and peripheral artery disease. OBJECTIVE: We sought to elucidate the mechanism of action and in vivo safety and efficacy of a novel iopromide-based paclitaxel-eluting balloon. METHODS: In vitro cytotoxicity of a novel DEB on human umbilical vein endothelial cells (HUVECs) and in vivo pharmacokinetics of DEB in a rabbit aorta abdominalis were assessed. Then, bare metal stents (BMS) …were implanted at both the proximal and distal sites of the rabbit aorta abdominalis. Stented vascular segments were immediately dilated with a bare balloon (control group) or the DEB (DEB group) randomly. Histological evaluation was performed in all treated segments at 28 days. Because paclitaxel is a tubulin-disrupting agent that binds preferentially to β -tubulin, we measured β -tubulin expression in aortal stent specimens via immunohistochemistry. RESULTS: We observed that DEB was compatible and could reduce neointimal hyperplasia compared with the bare balloon. Meanwhile, immunohistochemistry revealed that β -tubulin expression in the DEB group increased compared with the control group, indirectly suggesting successful uptake of paclitaxel by vessel walls after DEB dilation. CONCLUSIONS: The novel DEB is safe and has a favorable vascular healing response on neointimal hyperplasia. Show more

Keywords: Neointimal hyperplasia, paclitaxel-eluting balloon, pharmacokinetics

DOI: 10.3233/BME-151551

Citation: Bio-Medical Materials and Engineering, vol. 26, no. 1-2, pp. 79-88, 2015

Authors: Shankar, S. | Kesavan, D.

Article Type: Research Article

Abstract: The wear of the bearing surfaces of total disc replacement (TDR) is a key problem leads to reduction in the lifetime of the prosthesis and it mainly occurs due to the range of clearances of the articulating surface between the superior plate and core. The objective of this paper is to estimate the wear using finite element concepts considering the different radial clearances between the articulating surfaces of ceramic on ceramic type Lumbar Total Disc Replacement (LTDR). The finite element (FE) model was subjected to wear testing protocols according to loading profile of International Standards Organization (ISO) 18192 standards through …10 million cycles. The radial clearance value of 0.05 mm showed less volumetric wear when compared with other radial clearance values. Hence, low radial clearance values are suitable for LTDR to minimize the wear. Show more

Keywords: Wear, total disc replacement, ceramic on ceramic, radial clearance, finite element method

DOI: 10.3233/BME-151544

Citation: Bio-Medical Materials and Engineering, vol. 26, no. 1-2, pp. 89-96, 2015