Bio-Medical Materials and Engineering - Volume 22, issue 5

Authors: Arca, Turkan | Proffitt, Joanne | Genever, Paul

Article Type: Research Article

Abstract: Biomimetic scaffolds, delivered to the patient with or without cell loading, can offer improved treatments for a range of damaged or diseased tissues. In this work we evaluated the capacity of a cross-linked collagen-based implant material (Permacol™) to support the survival and growth of multipotent stromal cells or mesenchymal stem cells (MSCs) for potential applications in soft-tissue reconstruction and compared it to uncross-linked collagen. We showed, using confocal imaging, histology, quantitative analysis of seeding efficiencies by the MTT assay and Live/Dead analysis, that Permacol™ supported the adherence, growth and survival of MSCs preserving a healthy cell phenotype. MSCs infiltrated both …matrices, although migration rates were significantly higher on uncross-linked matrices for some donors. Our work demonstrates that Permacol™ could maintain human MSCs in long-term culture supporting its use as a cell-seeded biomaterial for durable and strong repair in tissue reconstruction. Show more

Keywords: Mesenchymal human stem cells, collagen implant material, regenerative, surgical

DOI: 10.3233/BME-2012-0716

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 5, pp. 261-276, 2012

Authors: Rieder, Philippe | Scherrer, Susanne | Filieri, Anna | Wiskott, H.W. Anselm | Durual, Stéphane

Article Type: Research Article

Abstract: Introduction: When applied onto SLA titanium, Titanium Nitride Oxide (TiNOx) coatings are known for their stimulating effect on osteoblast proliferation while maintaining a high degree of differentiation. Objective: To determine whether the stimulating effect of TiNOx coatings is or is not dependent of the metal substrate. Methods: A TiNOx coating was deposited on roughened stainless steel (SS-SLA-TiNOx). The proliferation and differentiation of human primary osteoblasts were determined and compared to that observed on standard SLA titanium. To this end, cell proliferation and gene expression were monitored for a time course of 3 weeks, with or without additional stimulation …by 100 nM 1.25(OH)2 vitamin D3. Results: A 1.5 fold increase in the proliferation rate of cells grown on SS-SLA-TiNOx as compared to Ti-SLA surfaces was observed. A high level of differentiation was also noted. Conclusion: TiNOx coatings yield similar proliferation and differentiation rates when applied onto roughened Ti and SS. This might translate into a more effective osseointegration of endosseous implants made of stronger metals than Ti. Show more

Keywords: Titanium-nitride-oxide coating, primary osteoblast, cell proliferation, cell differentiation, surface modification

DOI: 10.3233/BME-2012-0717

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 5, pp. 277-281, 2012

Authors: Kuboki, Yoshinori | Furusawa, Toshitake | Sato, Masaaki | Sun, Yongkun | Unuma, Hidero | Fujisawa, Ryuichi | Abe, Shigeaki | Akasaka, Tsukasa | Watari, Fumio | Takita, Hiroko | Sammons, Rachel

Article Type: Research Article

Abstract: The biochemical mechanism behind the strong binding between titanium and living bone has not been fully elucidated, in spite of worldwide clinical application of this phenomenon. We hypothesized that one of the core mechanisms may reside in the interaction between certain proteins in the host tissues and the implanted titanium. To verify the interaction between titanium and proteins, we chose the technique of chromatography in that titanium spherical beads (45 μm) were packed into a column to obtain a bed volume of 16×50 mm, which was eluted with phosphate buffered saline (PBS) and a straight gradient system made by using …PBS and 25 mM NaOH. Fetal calf serum, albumin, lysozyme, casein, phosvitin and dentin phosphoprotein (phosphophoryn) were applied to the column. Most part of albumin and lysozyme eluted with the breakthrough peak, indicating practically no affinity to titanium. Fetal bovine serum also eluted mostly as the breakthrough peak, but distinct retained peak was observed. On the other hand, α-casein, phosvitin and phosphophoryn exhibited a distinct retained peak separated from the breakthrough peak. We proposed that phosphate groups (phosphoserines) in the major phosphoproteins, α-casein, phosvitin and phosphophoryn may be involved in the binding of these proteins with titanium. Show more

Keywords: Titanium binding proteins, chromatography, phosphoprotein, caseins, phosvitin, dentin phosphoprotein

DOI: 10.3233/BME-2012-0718

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 5, pp. 283-288, 2012

Authors: Zhao, Lang | Wu, Chengtie | Lin, Kaili | Chang, Jiang

Article Type: Research Article

Abstract: Ideal scaffolds for bone tissue engineering require 3D interconnected porous structures, enough mechanical strength for hand of treatment as well as proper bioactivity and biodegradability. Calcium silicate (CaSiO3 , CS) scaffolds have been studied for bone tissue engineering application due to their excellent bioactivity. However, the main disadvantages of CS scaffolds are their low mechanical strength and high alkaline ionic products. In this study, sintered CS scaffolds were prepared and coated with poly(lactic-co-glycolic acid) (PLGA), and the effect of PLGA coating on the mechanical, biodegradable, bioactive properties and drug release of porous CS scaffolds were investigated. The results showed that …the PLGA-coated CS scaffolds maintained large pore size and high porosity. The compressive strength of PLGA/CS scaffolds was significantly improved compared to pure CS scaffolds, and increased with the increase of intrinsic viscosity and concentration of PLGA. In addition, the PLGA coating neutralized alkaline level resulted from the ionic products of CS scaffolds and reduced the pH value of biological solution during the degradation of scaffolds. It was found that PLGA/CS scaffolds still maintained excellent apatite-mineralization ability in SBF. Furthermore, the PLGA coating effectively inhibited the burst release and maintained a sustained release of drugs from the CS scaffolds. Our results indicate that the PLGA/CS scaffolds have great potential for bone tissue engineering application by the virtue of improved mechanical strength, and excellent bioactivity, degradation as well as drug-delivery property. Show more

Keywords: CaSiO_3 scaffolds, PLGA, compressive strength, drug release

DOI: 10.3233/BME-2012-0719

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 5, pp. 289-300, 2012

Authors: Yanagibayashi, Satoshi | Kishimoto, Satoko | Ishihara, Masayuki | Murakami, Kaoru | Aoki, Hiroshi | Takikawa, Megumi | Fujita, Masanori | Sekido, Mitsuru | Kiyosawa, Tomoharu

Article Type: Research Article

Abstract: To create a moist environment for wound healing, a hydrocolloid-sheet composed of alginate, chitin/chitosan and fucoidan (ACF-HS) has been developed as a functional wound dressing. ACF-HS gradually adsorbed medium without any maceration and the medium adsorption in vitro reached constant after 18 h. ACF-HS could effectively interact with and protect a healing-impaired wound in diabetic db/db mice, providing a good moist healing environment with exudate. Furthermore, the wound dressing could have other properties like ease of application and removal, and proper adherence. The aim of this study was to evaluate an accelerating effect of ACF-HS on wound healing for healing-impaired …wounds in diabetic db/db mice. Round full-thickness skin defects (12 mm in diameter) were made on the back of db/db mice to prepare healing-impaired wounds. After applying ACF-HS to the wounds, the mice were later killed and histological sections of the wound were prepared. Histological examinations showed significantly advanced granulation tissue and capillary formations in the wounds treated with ACF-HS on days 4, 9 and 14 compared with those in commercially available hydrocolloid wound dressing and non-treatment (control). Thus, ACF-HS may serve as a new wound dressing for diabetic healing-impaired wounds. Show more

Keywords: Alginate, chitin/chitosan, fucoidan, hydrocolloid-sheet, wound dressing

DOI: 10.3233/BME-2012-0720

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 5, pp. 301-310, 2012

Authors: Otsuka, Makoto | Kamei, Mina

Article Type: Research Article

Abstract: The purpose of this study was to evaluate drug content of hospital powder preparations using non-destructive, non-contact, short-term measurements with near-infrared spectroscopy (NIR). Antipyrine (0–50%) was mixed with additive powder, and packed with semi-transparent (SP) or transparent (TP) paper to obtain single packaged samples (SPP and TPP). Double packaged samples were obtained by packing TPP with TP. NIR spectra of the packaged samples were recorded using a NIR spectrometer with a fiber-optic probe. The best calibration model was determined to minimize the standard error of cross-validation (SEP) by the leave-out-one method in principal component regression (PCR). The calibration models for …SPP and TPP were calculated to be the minimum SEP based on one- and four-PC models by the PCR method, respectively. Plots of predicted and actual drug contents for SPP and TPP showed a straight line with a slope of 0.946 and 0.948, and γ of 0.965 and 0.980, respectively. On the other hand, the calibration model for the single and double TPP was obtained based on a three-PC model, and the plot of predicted and actual drug content showed a straight line with a slope of 0.942 and γ of 0.977. Show more

Keywords: Near-infrared spectroscopy, chemoinformetrics, drug content, hospital powder preparation, robust calibration model

DOI: 10.3233/BME-2012-0721

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 5, pp. 311-319, 2012

Authors: Lin, Hsin-Yi | Yeh, Chih-Tsung

Article Type: Research Article

Abstract: Controlled release carriers are often made into microspheres or tablets. Systematic and quantitative characterization of porous tissue engineered scaffolds as release carriers have not been done. Chitosan and chitosan crosslinked with various concentrations of genipin were made into porous tissue engineered scaffolds. Their thermal and enzymatic stabilities, hydrophobicities, porous structures, swelling and release properties, and compressional moduli were measured. The effects of scaffolds loaded with pentoxifylline (PTX) in suppressing inflammatory reactions in vitro were quantified. Fourier Transform Infrared spectra showed new bond formation after crosslinking chitosan with genipin. As genipin increased from 0.01% to 0.1%, the crosslinked chitosan scaffolds …swelled 0.5% to 1.8% less, had 1.9–5% decrease in PTX release efficiencies, became less wettable, were less favorable for initial cell attachment, had 4–20% increase in Young's modulus and were more resistant to enzymatic degradation. In vitro tests showed that when PTX was released more slowly from crosslinked scaffolds, PTX became more effective in suppressing macrophage cells from releasing IL-6 and TNF-α. Show more

Keywords: Chitosan, genipin, porous scaffolds, crosslinking, controlled release, anti-inflammation

DOI: 10.3233/BME-2012-0722

Citation: Bio-Medical Materials and Engineering, vol. 22, no. 5, pp. 321-332, 2012