In Vitro Bioactivity and Biocompatibility of Bio-Inspired Ti-6Al-4V Alloy Surfaces Modified by Combined Laser Micro/Nano Structuring

The bioactivity and biocompatibility play key roles in the success of dental and orthopaedic implants. Although most commercial implant systems use various surface microstructures, the ideal multi-scale topographies capable of controlling osteointegration have not yielded conclusive results. Inspired by both the isotropic adhesion of the skin structures in tree frog toe pads and the anisotropic adhesion of the corrugated ridges on the scales of Morpho butterfly wings, composite micro/nano-structures, including the array of micro-hexagons and oriented nano-ripples on titanium alloy implants, were respectively fabricated by microsecond laser direct writing and femtosecond laser-induced periodic surface structures, to improve cell adherence, alignment and proliferation on implants. The main differences in both the bioactivity in simulated body fluid and the biocompatibility in osteoblastic cell MC3T3 proliferation were measured and analyzed among Ti-6Al-4V samples with smooth surface, micro-hexagons and composite micro/nano-structures, respectively. Of note, bioinspired micro/nano-structures displayed the best bioactivity and biocompatibility after in vitro experiments, and meanwhile, the nano-ripples were able to induce cellular alignment within the micro-hexagons. The reasons for these differences were found in the topographical cues. An innovative functionalization strategy of controlling the osteointegration on titanium alloy implants is proposed using the composite micro/nano-structures, which is meaningful in various regenerative medicine applications and implant fields.

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Combined effects of multi-scale topographical cues on stable cell sheet formation and differentiation of mesenchymal stem cells

Biomaterials Science ◽

10.1039/c7bm00134g ◽

2017 ◽

Vol 5 (10) ◽

pp. 2056-2067 ◽

Cited By ~ 6

Author(s):

Sisi Li ◽

Shreyas Kuddannaya ◽

Yon Jin Chuah ◽

Jingnan Bao ◽

Yilei Zhang ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Cell Sheet ◽

Specific Cell ◽

Combined Effects ◽

Multi Scale ◽

Cell Responses ◽

Topographical Cues

To decipher specific cell responses to diverse and complex in vivo signals, it is essential to emulate specific surface chemicals, extra cellular matrix (ECM) components and topographical signals through reliable and easily reproducible in vitro systems.

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Cardiac myocytes respond differentially and synergistically to matrix stiffness and topography

10.1101/682930 ◽

2019 ◽

Author(s):

William Wan ◽

Kristen K. Bjorkman ◽

Esther S. Choi ◽

Amanda L. Panepento ◽

Kristi S. Anseth ◽

...

Keyword(s):

Cell Culture ◽

Cardiac Myocyte ◽

Cardiac Tissue ◽

Cellular Level ◽

Neonatal Rat ◽

Substrate Stiffness ◽

Tissue Stiffness ◽

Topographical Cues ◽

Cellular Alignment

AbstractDuring cardiac disease progression, myocytes undergo molecular, functional and structural changes, including increases in cell size and shape, decreased myocyte alignment and contractility. The heart often increases extracellular matrix production and stiffness, which affect myocytes. The order and hierarchy of these events remain unclear as available in vitro cell culture systems do not adequately model both physiologic and pathologic environments. Traditional cell culture substrates are 5-6 orders of magnitude stiffer than even diseased native cardiac tissue. Studies that do account for substrate stiffness often do not consider intercellular alignment and vice versa. We developed a cardiac myocyte culture platform that better recapitulates native tissue stiffness while simultaneously introducing topographical cues that promote cellular alignment. We show that stiffness and topography impact myocyte molecular and functional properties. We used a spatiotemporally-tunable, photolabile hydrogel platform to generate a range of stiffness and micron-scale topographical patterns to guide neonatal rat ventricular myocyte morphology. Importantly, these substrate patterns were of subcellular dimensions to test whether cells would spontaneously respond to topographical cues rather than an imposed geometry. Cellular contractility was highest and the gene expression profile was most physiologic on gels with healthy cardiac tissue stiffness. Surprisingly, while elongated patterns in stiff gels yielded the greatest cellular alignment, the cells actually had more pathologic functional and molecular profiles. These results highlight that morphological measurements alone are not a surrogate for overall cellular health as many studies assume. In general, substrate stiffness and micropatterning synergistically affect cardiac myocyte phenotype to recreate physiologic and pathologic microenvironments.Significance StatementHeart disease is accompanied by organ- and cellular-level remodeling, and deconvoluting their interplay is complex. Cellular-level change is best studied in vitro due to greater control and uniformity of cell types compared to animals. One common metric is degree of cellular alignment as misalignment of myocytes is a hallmark of disease. However, most studies utilize featureless culture surfaces that are orders of magnitude stiffer than, and do not mimic the scaffolding of, the heart. We developed a hydrogel platform with tunable stiffness and patterns providing topographical alignment cues. We cultured heart cells on and characterized multifactorial responses to these dynamic surfaces. Interestingly, conditions that yielded greatest alignment did not yield the healthiest functional and molecular state. Thus, morphology alone is not an indicator of overall cellular health.

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Osteogenic Differentiation, Antibacterial Activity and Biocompatibility of Zinc Oxide Minerals Substituted Hydroxyapatite Composite Coating on Titanium Alloy for Electrodeposition Technique

Asian Journal of Chemistry ◽

10.14233/ajchem.2020.22822 ◽

2020 ◽

Vol 32 (10) ◽

pp. 2633-2638

Author(s):

C. Santha ◽

S. Sathishkumar ◽

S. Sivakumar ◽

C. Sridevi ◽

A. Kamaraj

Keyword(s):

Antibacterial Activity ◽

Titanium Alloy ◽

Osteogenic Differentiation ◽

Composite Coating ◽

Cell Lines ◽

Composite Coatings ◽

Osteoblastic Cell ◽

Electrodeposition Technique ◽

X Ray

In present work, ZnO/Ce, Ag-HAP composite coating on titanium alloy is developed using electrodeposition technique. The surface characteristics of composite coatings were investigated by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) equipped with energy dispersive X-ray analysis (EDAX). The synthesized composite coatings showed the better antibacterial activity. in vitro Cell viability and osteogenic differentiation of the coatings was also studied by MC3T3-E1 human osteoblastic cell lines. The composite coating was found to be non-toxic against MC3T3-E1 cell lines at different incubation day proved the excellent bioactive of these coatings.

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Bioengineered in vitro skeletal muscles as new tools for muscular dystrophies preclinical studies

Journal of Tissue Engineering ◽

10.1177/2041731420981339 ◽

2021 ◽

Vol 12 ◽

pp. 204173142098133

Author(s):

Juan M. Fernández-Costa ◽

Xiomara Fernández-Garibay ◽

Ferran Velasco-Mallorquí ◽

Javier Ramón-Azcón

Keyword(s):

Skeletal Muscle ◽

Tissue Engineering ◽

Electrical Stimulation ◽

Skeletal Muscles ◽

Screening Tools ◽

Muscular Dystrophies ◽

Preclinical Studies ◽

Technological Advances ◽

Topographical Cues

Muscular dystrophies are a group of highly disabling disorders that share degenerative muscle weakness and wasting as common symptoms. To date, there is not an effective cure for these diseases. In the last years, bioengineered tissues have emerged as powerful tools for preclinical studies. In this review, we summarize the recent technological advances in skeletal muscle tissue engineering. We identify several ground-breaking techniques to fabricate in vitro bioartificial muscles. Accumulating evidence shows that scaffold-based tissue engineering provides topographical cues that enhance the viability and maturation of skeletal muscle. Functional bioartificial muscles have been developed using human myoblasts. These tissues accurately responded to electrical and biological stimulation. Moreover, advanced drug screening tools can be fabricated integrating these tissues in electrical stimulation platforms. However, more work introducing patient-derived cells and integrating these tissues in microdevices is needed to promote the clinical translation of bioengineered skeletal muscle as preclinical tools for muscular dystrophies.

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Understanding the multi-scale structure, physicochemical properties and in vitro digestibility of citrate naked barley starch induced by non-thermal plasma

Food & Function ◽

10.1039/d1fo00678a ◽

2021 ◽

Author(s):

Huishan Shen ◽

Xiangzhen Ge ◽

Bo Zhang ◽

Chunyan Su ◽

Qian Zhang ◽

...

Keyword(s):

Physicochemical Properties ◽

Thermal Plasma ◽

Scale Structure ◽

In Vitro Digestibility ◽

Multi Scale ◽

Naked Barley ◽

Starch Modification ◽

Plasma Pretreatment ◽

Non Thermal Plasma

Non-thermal plasma is an emerging and effective starch modification technology. In this paper, plasma pretreatment was used to modify the citrate naked barley starch for enhancing the accessibility of citric...

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A Novel Bioreactor for the Mechanical Stimulation of Clinically Relevant Scaffolds for Muscle Tissue Engineering Purposes

Processes ◽

10.3390/pr9030474 ◽

2021 ◽

Vol 9 (3) ◽

pp. 474

Author(s):

Silvia Todros ◽

Silvia Spadoni ◽

Edoardo Maghin ◽

Martina Piccoli ◽

Piero G. Pavan

Keyword(s):

Mechanical Stimulation ◽

Strain Range ◽

Tensile Tests ◽

Muscular Tissue ◽

Fe Model ◽

Mechanical Stimuli ◽

Physiological Strain ◽

Cellular Alignment ◽

Stimulation Of

Muscular tissue regeneration may be enhanced in vitro by means of mechanical stimulation, inducing cellular alignment and the growth of functional fibers. In this work, a novel bioreactor is designed for the radial stimulation of porcine-derived diaphragmatic scaffolds aiming at the development of clinically relevant tissue patches. A Finite Element (FE) model of the bioreactor membrane is developed, considering two different methods for gripping muscular tissue patch during the stimulation, i.e., suturing and clamping with pliers. Tensile tests are carried out on fresh and decellularized samples of porcine diaphragmatic tissue, and a fiber-reinforced hyperelastic constitutive model is assumed to describe the mechanical behavior of tissue patches. Numerical analyses are carried out by applying pressure to the bioreactor membrane and evaluating tissue strain during the stimulation phase. The bioreactor designed in this work allows one to mechanically stimulate tissue patches in a radial direction by uniformly applying up to 30% strain. This can be achieved by adopting pliers for tissue clamping. Contrarily, the use of sutures is not advisable, since high strain levels are reached in suturing points, exceeding the physiological strain range and possibly leading to tissue laceration. FE analysis allows the optimization of the bioreactor configuration in order to ensure an efficient transduction of mechanical stimuli while preventing tissue damage.

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