Higher Cell Adhesion Research Articles

Intravaginal Administration of Human Type III Collagen-Derived Biomaterial with High Cell-Adhesion Activity to Treat Vaginal Atrophy in Rats.

Vaginal atrophy (VA) is the thinning and drying of the vaginal walls, which can lead to a variety of symptoms. VA is usually initiated by decreasing estrogen levels in post-menopausal women; so, the traditional treatment of VA is hormone therapy (HT). Here, we sought nonhormonal therapies aimed at treating this condition safely and effectively. Collagen is an excellent biomaterial and has important biological functions in skin and mucosal tissues. In particular, collagen can bind to epithelial cells to promote proliferation and differentiation. In this study, recombinant protein T16, which was derived from human type III collagen to provide potent cell-adhesion activity, was used as a safe alternative therapy to treat VA in ovariectomy rat models. After T16 was administered intravaginally for 2 weeks, the autologous collagen arrangement was improved in the epithelium and muscle layer of the rat vagina, and the thickness of epithelium tissue also increased significantly. Compared with the sham group, collagen therapy was found to influence the expression levels of several important proteins in the vaginal tissue, resulting in the upregulation of TIMP-1, Collagen I, Collagen III, Ki-67, VEGF, and AQP-2 and the downregulation of MMP-1 and IL-6. Cells in the collagen treatment group exhibited better proliferation and less apoptosis properties. These results not only provide support for additional animal experiments to further evaluate collagen therapy in VA treatment but also suggest the potential for wide applications of collagen biomaterials with high cell-adhesion activities.

Evaluation of paraffin wax and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) blend patch for tissue engineering

ABSTRACT In the study, we aimed to develop a multipurpose tissue patch for the repairment of various tissue defects. Poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) was blended with paraffin wax, and the chemical composition of the membranes was determined by the FTIR and RAMAN spectroscopy. The surface area of the PHBHHx and PHBHHx/Paraffin wax were determined as (38,79 m2/g) and (81,108 m2/g), respectively. The DMA and DSC results revealed that blending with paraffin wax, increased the percentage of elongation of the PHBHHx membrane by 7,6% and reduced the modulus of elasticity. While the elongation at break of PHBHHx tissue patch was 22,463% (standard error = ± 2,476), addition of Paraffin wax increased the value to 30,038% (standard error = ± 7,228). The antioxidant capacity significantly increased and p53/TP53 levels decreased after blending with paraffin. In conclusion, PHBHHx/paraffin wax blend patches can be considered as a promising biomaterial due to their high cell adhesion capacity depending on its increased surface area, fine anti-oxidant properties, and appropriate mechanical properties.

Mechanics Regulate Human Embryonic Stem Cell Self-Organization to Specify Mesoderm

Embryogenesis is directed by morphogens that induce differentiation within a defined tissue geometry. Tissue organization is mediated by cell-cell and cell-extracellular matrix (ECM) adhesions and is modulated by cell tension and tissue-level force. Whether cell tension regulates development by directly influencing morphogen signaling remains unclear. Human embryonic stem cells (hESCs) exhibit an intrinsic capacity for self-organization that motivates their use as a tractable model of early human embryogenesis. We engineered patterned substrates that enhance cell-cell interactions to direct the self-organization of cultured hESCs into “gastrulation-like” nodes. Tissue geometries that generate local nodes of high cell-adhesion tension and induce these self-organized tissue nodes drive BMP4-dependent gastrulation by enhancing phosphorylation and nuclear translocation of β-catenin to promote Wnt signaling and mesoderm specification. The findings underscore the interplay between tissue organization, cell tension, and morphogen-dependent differentiation, and demonstrate that cell- and tissue-level forces directly regulate cell fate specification in early human development.

The effect of nano-size second precipitates on the structure, apatite-inducing ability and in-vitro biocompatibility of Ti-29Nb-14Ta-4.5Zr alloy.

The apatite formation and in-vitro biocompatibility of Ti-29Nb-14Ta-4.5Zr (TNTZ) alloy reinforced by various nano-sized phases of α″, α, and ω in the β matrix have been studied. The electrochemical performances of the elaborated microstructures have been assessed through potentiodynamic polarization in the simulated body fluid (SBF) and interestingly, the β+ω specimen exhibited an extraordinary corrosion resistance compared to the others. This was attributed to the uniform distribution, spherical morphology and coherent interface of the ω nano-precipitates. The polarization tests in simulated body fluid showed the high tendency of apatite formation on the surface of the β- matrix contained ω precipitates. The in-vitro cytotoxicity analysis employing MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay showed >85% cell viability of the TNTZ alloy reinforced by nano-ω precipitations. Since this specimen showed the highest cell adhesion as well, it introduces this structure as a promising high potential candidate for biomedical applications due to its high corrosion resistance, biocompatibility, ultra-low cytotoxicity, and good cell adhesion.

Biofabrication of Gelatin Tissue Scaffolds with Uniform Pore Size via Microbubble Assembly

The control of pore size and uniform porosity remains as an important challenge in gelatin scaffolds. The precise control in building blocks of tissue scaffolds without any additional porogen is possible with costly equipment and techniques, though some pre‐requirements for polymeric material, such as photo‐polymerizability or sintering ability, may be needed prior to construction. Herein, a method for the fabrication of gelatin scaffolds with homogenous porosity using simple T‐junction microfluidics is described. The size of the microbubbles is precisely controlled with 5% deviation from the average. Porous gelatin scaffolds are obtained by building‐up the monodispersed microbubbles in dilute cross‐linker solutions. The effect of cross‐linker density on pore diameter is also investigated. After cross‐linking, pore size of the resultant five scaffold groups are precisely controlled as 135 ± 11, 193 ± 11, 216 ± 9, 231 ± 5, and 250 ± 12 µm. Porosity ratios above 65% are achieved in every sample group. According to the cell culture experiments, structures support high cell adhesion, viability, and migration through the porous network via interconnectivity. This study offers a practical and economical approach for the preparation of porous gelatin scaffolds with homogenous porosity which can be utilized in diverse tissue engineering applications.

Polycaprolactone/gelatin-based scaffolds with tailored performance: in vitro and in vivo validation.

Nanofibrous scaffolds composed of polycaprolactone (PCL) and gelatin (Ge) were obtained through a hydrolytic assisted electrospinning process. The PCL-to-Ge proportion (100/0 to 20/80), as well as the dissolution time (24, 48, 72, 96, 120 h) into a 1:1 formic/acetic acid solvent before electrospinning were modified to obtain the different samples. A strong influence of these factors on the physicochemical properties of the scaffolds was observed. Higher Ge percentage reduced crystallinity, allowed a uniform morphology and increased water contact angle. The increase in the dissolution time considerably reduced the molar mass and, subsequently, fibre diameter and crystallinity were affected. During in vitro biocompatibility tests, higher cell adhesion and proliferation were found for the 60/40, 50/50 and 40/60 PCL/Ge compositions that was corroborated by MTT assay, fluorescence and microscopy. A weakened structure, more labile to the in vitro degradation in physiologic conditions was found for these compositions with higher dissolution times (72 and 96 h). Particularly, the 40/60 PCL/Ge scaffolds revealed an interesting progressive degradation behaviour as a function of the dissolution time. Moreover, these scaffolds were non-inflammatory, as revealed by the pyrogen test and after the 15-day subcutaneous in vivo implantation in mice. Finally, a reduction of the scar tissue area after infarction was found for the 40/60 PCL/Ge scaffolds electrospun after 72 h implanted in rat hearts. These results are especially interesting and represent a feasible way to avoid undesired inflammatory reactions during the scaffold assimilation.

Microcarriers with Controllable Size via Electrified Liquid Jets and Phase Separation Technique Promote Cell Proliferation and Osteogenic Differentiation.

Differently sized poly(lactic-co-glycolic) microspheres were efficiently prepared with electrified liquid jets and a phase separation technique for a wide range of applications. Higher polymer concentrations tended to form larger microcarriers. Polymer concentration can obviously affect bead or fiber formation resulting beads and fiber morphologies. As the voltage of electrostatic field and the needle size increased, the size of microcarriers decreased remarkably. The most suitable concentration of ethanol in the collecting solution might be lower than 55%. The resulting composite microcarriers have significantly narrow size distribution, controllable sizes, and high cell adhesion, growth, and osteodifferentiation abilities.

Biofabrication of Gelatin Tissue Scaffolds with Uniform Pore Size via Microbubble Assembly

AbstractThe control of pore size and uniform porosity remains as an important challenge in gelatin scaffolds. The precise control in building blocks of tissue scaffolds without any additional porogen is possible with costly equipment and techniques, though some pre‐requirements for polymeric material, such as photo‐polymerizability or sintering ability, may be needed prior to construction. Herein, a method for the fabrication of gelatin scaffolds with homogenous porosity using simple T‐junction microfluidics is described. The size of the microbubbles is precisely controlled with 5% deviation from the average. Porous gelatin scaffolds are obtained by building‐up the monodispersed microbubbles in dilute cross‐linker solutions. The effect of cross‐linker density on pore diameter is also investigated. After cross‐linking, pore size of the resultant five scaffold groups are precisely controlled as 135 ± 11, 193 ± 11, 216 ± 9, 231 ± 5, and 250 ± 12 µm. Porosity ratios above 65% are achieved in every sample group. According to the cell culture experiments, structures support high cell adhesion, viability, and migration through the porous network via interconnectivity. This study offers a practical and economical approach for the preparation of porous gelatin scaffolds with homogenous porosity which can be utilized in diverse tissue engineering applications.

A high-toughness and high cell adhesion polyvinyl alcohol（PVA-hyaluronic acid (HA)-human-like collagen (HLC) composite hydrogel for cartilage repair

Polyvinyl alcohol (PVA) has good mechanical stability and flexibility. However, PVA hydrogels of low compressive strength and low cell adhesion is still considered difficult to apply to tissue engineering cartilage. In this paper, we prepared PVA-HA-HLC hydrogel by freeze-thaw method. The results showed that the hydrogel had an average pore diameter of 100–300 μm, a porosity of 94.52%, a maximum compressive strain of 90%, and a compressive strength of 5.56 MPa. Animal cartilage defect test results showed that PVA-HA-HLC hydrogel repaired cartilage defects. In short, PVA-HA-HLC hydrogels could be used as cartilage repair scaffold.

Screening of perfused combinatorial 3D microenvironments for cell culture

Biomaterials combining biochemical and biophysical cues to establish close-to-extracellular matrix (ECM) models have been explored for cell expansion and differentiation purposes. Multivariate arrays are used as material-saving and rapid-to-analyze platforms, which enable selecting hit-spotted formulations targeting specific cellular responses. However, these systems often lack the ability to emulate dynamic mechanical aspects that occur in specific biological milieus and affect physiological phenomena including stem cells differentiation, tumor progression, or matrix modulation. We report a tailor-made strategy to address the combined effect of flow and biochemical composition of three-dimensional (3D) biomaterials on cellular response. We suggest a simple-to-implement device comprising (i) a perforated platform accommodating miniaturized 3D biomaterials and (ii) a bioreactor that enables the incorporation of the biomaterial-containing array into a disposable perfusion chamber. The system was upscaled to parallelizable setups, increasing the number of analyzed platforms per independent experiment. As a proof-of-concept, porous chitosan scaffolds with 1 mm diameter were functionalized with combinations of 5 ECM and cell-cell contact-mediating proteins, relevant for bone and dental regeneration, corresponding to 32 protein combinatorial formulations. Mesenchymal stem cells adhesion and production of an early osteogenic marker were assessed on-chip on static and under-flow dynamic perfusion conditions. Different hit-spotted biomaterial formulations were detected for the different flow regimes using direct image analysis. Cell-binding proteins still poorly explored as biomaterials components – amelogenin and E-cadherin – were here shown as relevant cell response modulators. Their combination with ECM cell-binding proteins – fibronectin, vitronectin, and type 1 collagen – rendered specific biomaterial combinations with high cell adhesion and ALP production under flow. The developed versatile system may be targeted at widespread tissue regeneration applications, and as a disease model/drug screening platform. Statement of SignificanceA perfusion system that enables cell culture in arrays of three-dimensional biomaterials under dynamic flow is reported. The effect of 31 cell-binding protein combinations in the adhesion and alkaline phosphatase (ALP) production of mesenchymal stem cells was assessed using a single bioreactor chamber. Flow perfusion was not only assessed as a classical enhancer/accelerator of cell growth and early osteogenic differentiation. We hypothesized that flow may affect cell-protein interactions, and that key components driving cell response may differ under static or dynamic regimes. Indeed, hit-spotted formulations that elicited highest cell attachment and ALP production on static cell culture differed from the ones detected for dynamic flow assays. The impacting role of poorly studied proteins as E-cadherin and amelogenin as biomaterial components was highlighted.

Synthesis and characterization of electrospun nanofibrous tissue engineering scaffolds generated from in situ polymerization of ionomeric polyurethane composites

Tissue scaffolds need to be engineered to be cell compatible, have timely biodegradable character, be functional with respect to providing niche cell support for tissue repair and regeneration, readily accommodate multiple cell types, and have mechanical properties that enable the simulation of the native tissue. In this study, electrospun degradable polar hydrophobic ionic polyurethane (D-PHI) scaffolds were generated in order to yield an extracellular matrix-like structure for tissue engineering applications. D-PHI oligomers were synthesized, blended with a degradable linear polycarbonate polyurethane (PCNU), and electrospun with simultaneous in situ UV cross-linking in order to generate aligned nanofibrous scaffolds in the form of elastomeric composite materials. The D-PHI/PCNU scaffold fibre morphology, cross-linking efficiency, surface nature, mechanical properties, in vivo degradation and integration, as well as in vitro cell compatibility were characterized. The results showed that D-PHI/PCNU scaffolds had a high cross-linking efficiency, stronger polar nature, and lower stiffness relative to PCNU scaffolds. In vivo, the D-PHI/PCNU scaffold degraded relatively slowly, thereby enabling new tissue time to form and yielding very good integration with the latter tissue. Based on a study with A10 vascular smooth muscle cells, the D-PHI/PCNU scaffold was able to support high cell viability, adhesion, and expression of typical smooth muscle cell markers after a 7-day culture period, which was comparable to PCNU scaffolds. These characterization results demonstrate that the unique properties of a D-PHI/PCNU scaffold, combined with the benefits of electrospinning, could allow for the generation of a tissue engineered scaffold that mimics important aspects of the native extracellular matrix and could be used for functional tissue regeneration. Statement of SignificanceTissue engineered scaffolds should recapitulate native extracellular matrix features. This study investigates the processing of a classical polycarbonate polyurethane (PCNU) with a cross-linked and degradable ionomeric polyurethane (D-PHI), polymerized via in situ rapid light curing to yield a 3-dimensional co-electrospun nanofibre matrix with chemical diversity and low modulus character. This research advances the use of D-PHI for tissue engineering applications by providing a facile means of changing physical and chemical properties in classical PCNUs without the need to adjust spinning viscosities of the base polymer. Further, the in vivo and cell culture findings set the stage for introducing unique elastic materials which inherently support wound healing, repair, and regeneration in tissues, for applications that require the recapitulation of native extracellular matrix physical features.

Rapid mineralization of hierarchical poly(l-lactic acid)/poly(ε-caprolactone) nanofibrous scaffolds by electrodeposition for bone regeneration.

Introduction: Hierarchical nanofibrous scaffolds are emerging as a promising bone repair material due to their high cell adhesion activity and nutrient permeability. However, the existing method for hierarchical nanofibrous scaffolds fabrication is complicated and not perfectly suitable for further biomedical application in view of both structure and function. In this study, we constructed a hierarchical nanofibrous poly (l-lactic acid)/poly(ε-caprolactone) (PLLA/PCL) scaffold and further evaluated its bone healing ability.Methods: The hierarchical PLLA/PCL nanofibrous scaffold (PLLA/PCL) was prepared by one-pot TIPS and then rapidly mineralized at room temperature by an electrochemical deposition technique. After electrode-positioning at 2 V for 2 hrs, a scaffold coated with hydroxyapatite (M-PLLA/PCL) could be obtained.Results: The pore size of the M-PLLA/PCL scaffold was hierarchically distributed so as to match the biophysical structure for osteoblast growth. The M-PLLA/PCL scaffold showed better cell proliferation and osteogenesis activity compared to the PLLA/PCL scaffold. Further in vivo bone repair studies indicated that the M-PLLA/PCL scaffold could accelerate defect healing in 12 weeks.Conclusion: The results of this study implied that the as-prepared hydroxyapatite coated hierarchical PLLA/PCL nanofibrous scaffolds could be developed as a promising material for efficient bone tissue repair after carefully tuning the TIPS and electrodeposition parameters.

Synthesis and Characterization of Electrospun Nanofibrous Tissue Engineering Scaffolds Generated from in Situ Polymerization of Ionomeric Polyurethane Composites

Tissue scaffolds need to be engineered to be cell compatible, have timely biodegradable character, be functional with respect to providing niche cell support for tissue repair and regeneration, readily accommodate multiple cell types, and have mechanical properties that enable the simulation of the native tissue. In this study, electrospun degradable polar hydrophobic ionic polyurethane (D-PHI) scaffolds were generated in order to yield an extracellular matrix-like structure for tissue engineering applications. D-PHI oligomers were synthesized, blended with a degradable linear polycarbonate polyurethane (PCNU), and electrospun with simultaneous in situ UV cross-linking in order to generate aligned nanofibrous scaffolds in the form of elastomeric composite materials. The D-PHI/PCNU scaffold fibre morphology, cross-linking efficiency, surface nature, mechanical properties, in vivo degradation and integration, as well as in vitro cell compatibility were characterized. The results showed that D-PHI/PCNU scaffolds had a high cross-linking efficiency, stronger polar nature, and lower stiffness relative to PCNU scaffolds. In vivo, the D-PHI/PCNU scaffold degraded relatively slowly, thereby enabling new tissue time to form and yielding very good integration with the latter tissue. Based on a study with A10 vascular smooth muscle cells, the D-PHI/PCNU scaffold was able to support high cell viability, adhesion, and expression of typical smooth muscle cell markers after a 7-day culture period, which was comparable to PCNU scaffolds. These characterization results demonstrate that the unique properties of a D-PHI/PCNU scaffold, combined with the benefits of electrospinning, could allow for the generation of a tissue engineered scaffold that mimics important aspects of the native extracellular matrix and could be used for functional tissue regeneration.

Enhancing the Stability, Hydrophilicity, Mechanical and Biological Properties of Electrospun Polycaprolactone in Formic Acid/Acetic Acid Solvent System

Electrospun polycaprolactone is widely used in the medical field. Formic acid/acetic acid (FA/AA) solvent system is one of the safest solvents used for the production of nano-range polycaprolactone (PCL) fibers, although it has a very low stability. In the present study, the stability of PCL in FA/AA system was enhanced by sodium hydrogen carbonate (NaHCO3) addition with three different concentrations (1, 5 and 10 wt%). The resultant electrospun fiber properties were compared to that treated by alkaline hydrolysis. The viscosity and conductivity of PCL solutions were measured before the electrospinning process. Moreover, the obtained electrospun PCL mats were characterized by SEM, FT-IR, XRD, contact angle measurements, degradability, swelling, and mechanical properties, as well as their ability to enhance the proliferation and adhesion of mesenchymal stem cells (MSCs). It was found that NaHCO not only enhanced the fiber properties, such as hydrophilicity, degradability and mechanical properties but also had a significant effect on the stability of polycaprolactone in FA/AA solvent system, as well as an enhanced MSCs proliferation and adhesion. Although hydrolyzed PCL showed high cell viability and adhesion, it showed much lower mechanical properties (0.7 MPa) compared to neat PCL (1.3 MPa) and PCL-NaHCO3 (5.1 MPa). In conclusion, the addition of NaHCO3 to PCL solution prior to the electrospinning process represents a novel and an effective approach to improve the physicochemical properties and biological behavior of electrospun PCL mats for tissue engineering application.

In Vitro Assessment of the Functional Dynamics of Titanium with Surface Coating of Hydroxyapatite Nanoparticles.

Manipulation of implant surface characteristics constitutes a promising strategy for improving cell growth and tissue response on a variety of materials with different surface topographies. Mesenchymal progenitor cells with a capacity to respond to titanium surface stimuli and differentiate into osteoblasts were used to perform comparative tests between two different implant topographies, including their functional interaction with pre-osteoblasts directly seeded onto the implants. Functional analysis of nanostructured implant surfaces was performed by in vitro assay analysis. The machined surface of titanium implants (mach group) was used as a control and compared with a nanoparticle HA activated surface implant (nano group), developed by the deposition of pure crystalline hydroxyapatite. Cell culture on the nano group surface resulted in higher cell adhesion and cultured osteoblast viability compared with the mach group. Scanning electron microscope (SEM) images revealed a stable interaction, indicated by the presence of focal cell adhesion formation. These results together with positive mineralization assays showed the nano group to be an excellent scaffold for bone-implant integration.

Thermal annealed silk fibroin membranes for periodontal guided tissue regeneration.

Guided tissue regeneration (GTR) is a surgical procedure applied in the reconstruction of periodontal defects, where an occlusive membrane is used to prevent the fast-growing connective tissue from migrating into the defect. In this work, silk fibroin (SF) membranes were developed for periodontal guided tissue regeneration. Solutions of SF with glycerol (GLY) or polyvinyl alcohol (PVA) where prepared at several weight ratios up to 30%, followed by solvent casting and thermal annealing at 85 °C for periods of 6 and 12 h to produce high flexible and stable membranes. These were characterized in terms of their morphology, physical integrity, chemical structure, mechanical and thermal properties, swelling capability and in vitro degradation behavior. The developed blended membranes exhibited high ductility, which is particular relevant considering the need for physical handling and adaptability to the defect. Moreover, the membranes were cultured with human periodontal ligament fibroblast cells (hPDLs) up to 7 days. Also, the higher hydrophilicity and consequent in vitro proteolytic degradability of these blends was superior to pure silk fibroin membranes. In particular SF/GLY blends demonstrated to support high cell adhesion and viability with an adequate hPDLs' morphology, make them excellent candidates for applications in periodontal regeneration.

Ciprofloxacin‐Loaded Ceramic/Polymer Composite Coatings on Ti with Improved Antibacterial and Corrosion Resistance Properties for Orthopedic Applications

AbstractPast few decades witnessed the upcoming of osteomyelitis which is a challenging infectious bone disease. Complications related to this infection is encountered by local drug delivery via orthopedic surgery. In this work, TiO2‐SiO2 based bioceramics coatings were fabricated on Ti alloy by anodization method using sulphuric acid and Sodium silicofluoride (SSF) as an electrolyte. Plasma polymerized ethylenediamine (PPEDA) thin film deposited on composites by inductively coupled plasma chemical vapor deposition and followed by ciprofloxacin were used as a model drug by electrodeposition method. The resultant coatings were characterized by FTIR, XRD, FESEM, EDAX and AFM techniques. The mechanical behavior of the composite coatings was evaluated using thickness and hardness tester and electrochemical properties were studied in Ringer's solution. Similarly, CIP@PPEDA/TiO2‐SiO2 composite coating on Ti alloy shows good corrosion resistance and better antibacterial efficacy as well as L929 fibroblast cell line, which exhibited a high cell adhesion and high cell viability compared than TiO2‐SiO2 and PPEDA/TiO2‐SiO2 coatings. All these results suggest that, this newly developed composite coating exhibits superior bioactivity and improved anticorrosion performance on Ti specimen and can be a potential candidate for orthopedic applications.

Comparative studies on thin polycaprolactone-tricalcium phosphate composite scaffolds and its interaction with mesenchymal stem cells

BackgroundHybrid scaffolds combining biodegradable polymers and ceramic particles for control of cell adhesion and proliferation are interesting materials for tissue engineering applications. Combinations of biodegradable polymers and ceramics are to provide higher beneficial functionalities to tissue engineering scaffolds with addition of different cell specific bio-factors. Many such hybrid combinations have been reported by several researchers around the world by using various methods and solvents as well as bioactive matrix polymers to fabricate such biomaterials. However, thin hybrid scaffolds with high porosity, cell adhesion factors and biodegradability, as well as the ability to support stem cells often require tedious processes like electrospinning, freeze drying, etc. A simple method to develop porous biodegradable hybrid scaffolds with proper cell adhesion factors is still the need of the hour in tissue engineering and regenerative medicine.MethodThin biodegradable poly(ε-caprolactone) (PCL) based hybrid scaffolds were developed in combination with α-tricalcium phosphate (TCP) particles, gelatin and fibronectin separately and the fabricated scaffolds were evaluated systematically using human mesenchymal stem cells (hMSCs) for tissue engineering applications. A simple modified solvent casting method combined with gas foaming process was used to develop porous thin hybrid structures and compared their properties with those of corresponding non-porous hybrid scaffolds. The TCP particles distribution, morphology, biodegradability and functional groups of the different hybrid scaffolds were analyzed using energy-dispersive X-ray spectroscopy (EDX), light microscopy/scanning electron microscopy (SEM), buffer solutions and Fourier-transform infrared spectroscopy (FTIR), respectively The cellular and tissue regeneration behaviors such as in vitro cell attachment (live/dead assay), cell proliferation (CCK-8 assay) and histological studies were performed using hMSCs.ResultsThin PCL-based hybrid scaffolds were fabricated using modified solvent casting method. Homogeneous distribution of TCP particles in the scaffolds were confirmed by EDX. Cellular interactions of the hybrid scaffolds demonstrated overall higher cell adhesion, proliferation and tissue regeneration on the non-porous thin films of PCL-TCP, PCL-TCP-gelatin and PCL-TCP-fibronectin. Coating of fibronectin was remarkable in induction of cell adhesion and proliferation.ConclusionsThe experimental results revealed that diversely designed PCL-TCP thin hybrid films showed high cell interaction and proliferation with hMSCs. From the results of the cell viability, attachment, proliferation and histological analyses as well as their biodegradation and coating effects, we conclude that these thin PCL-TCP hybrid films are suitable for tissue engineering applications.

High Epithelial Cell Adhesion Molecule–Positive Circulating Tumor Cell Count Predicts Poor Survival of Patients with Unresectable Hepatocellular Carcinoma Treated with Transcatheter Arterial Chemoembolization

PurposeTo assess the role of epithelial cell adhesion molecule (EpCAM)–positive circulating tumor cell (CTC) count in predicting survival outcomes of transcatheter arterial chemoembolization in patients with unresectable hepatocellular carcinoma (HCC). Materials and MethodsEpCAM-positive CTC counts were prospectively determined via CellSearch in peripheral blood of 97 patients with unresectable HCC treated with chemoembolization. The impact of each CTC cutoff point on overall survival (OS) was evaluated by univariate Cox regression analysis. Based on hazard ratio, patients were divided into 3 groups with low (CTC count 0/1), moderate (CTC count 2–5), and high (CTC count ≥ 6) levels. Correlation of CTC counts with survival was assessed by Cox proportional-hazards model. ResultsEighty-nine patients met inclusion criteria and were enrolled. On multivariate Cox regression analysis, CTC count was found to be an independent predictor of OS (P = .049) and progression-free survival (PFS; P = .007) in patients treated with chemoembolization. After adjustment for confounding factors, mortality risks in the high- and moderate-level groups were 2.819 times (95% confidence interval [CI], 1.218–6.526; P = .016) and 1.301 times (95% CI, 0.630–2.685; P = .477) greater, respectively, than in the low-level group. The risk of progression was 3.705 fold higher in the high-level group (95% CI, 1.628–8.433; P = .002) and 1.648 fold higher in the moderate-level group (95% CI, 0.843–3.223; P = .144) vs the low-level group. ConclusionsHigh EpCAM-positive CTC count predicts poor survival of patients with unresectable HCC treated with chemoembolization.

Biological and Mechanical Properties of Platelet-Rich Fibrin Membranes after Thermal Manipulation and Preparation in a Single-Syringe Closed System

Platelet-rich fibrin (PRF) membrane is a three-dimensional biodegradable biopolymer, which consists of platelet derived growth factors enhancing cell adhesion and proliferation. It is widely used in soft and hard tissue regeneration, however, there are unresolved problems with its clinical application. Its preparation needs open handling of the membranes, it degrades easily, and it has a low tensile strength which does not hold a suture blocking wider clinical applications of PRF. Our aim was to produce a sterile, suturable, reproducible PRF membrane suitable for surgical intervention. We compared the biological and mechanical properties of PRF membranes created by the classical glass-tube and those that were created in a single-syringe closed system (hypACT Inject), which allowed aseptic preparation. HypACT Inject device produces a PRF membrane with better handling characteristics without compromising biological properties. Freeze-thawing resulted in significantly higher tensile strength and higher cell adhesion at a lower degradation rate of the membranes. Mesenchymal stem cells seeded onto PRF membranes readily proliferated on the surface of fresh, but even better on freeze/thawed or freeze-dried membranes. These data show that PRF membranes can be made sterile, more uniform and significantly stronger which makes it possible to use them as suturable surgical membranes.