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UV photofunctionalization of Zirconia-based materials for abutment fabrication is a promising approach that might influence the formation of a sound peri-implant seal, thus promoting long-term soft and hard tissue implant integration. This study aimed to evaluate the effect of UV treatment of test specimens made by two different ZnO2-based ceramic materials on the hydrophilicity, cell cytotoxicity, and proliferation of human gingival fibroblasts (HGFs). Two Zirconia-based materials, high-translucent and ultra-translucent multi-layered Zirconia (Katana, Kuraray Noritake, Japan), were used to prepare a total of 40 specimens distributed in two equally sized groups based on the material (n = 20). The same surface finishing protocol was applied for all specimens, as suggested by the manufacturer. Half the specimens from each group were treated with UV-C light for 48 h. Water contact angle (WCA), fibroblast cytotoxicity, and proliferation were investigated. The WCA values for the high-translucent Zirconia ranged from 69.9° ± 6.4° to 73.7° ± 13.9° for the treated/non-treated specimens and from 79.5° ± 12.8° to 83.4° ± 11.4° for the ultra-translucent multi-layered Zirconia, respectively. However, the difference was insignificant (F(16) = 3.50, p = 0.292). No significant difference was observed for the fibroblast cytotoxicity test. The results for proliferation revealed a significant difference, which was material-dependent (F(8) = 9.58, p = 0.005). We found that UV surface photofunctionalization of ZrO2-based materials alters the human gingival fibroblast cell viability, which might produce favourable results for cell proliferation.

To facilitate artificial bone construct integration into a patient's body, scaffolds are enriched with different biologically active molecules. Among various scaffold decoration techniques, coating surfaces with cell-derived extracellular matrix (ECM) is a rapidly growing field of research. In this study, for the first time, this technology was applied using primary dental pulp stem cells (DPSCs) and tested for use in artificial bone tissue construction.Rat DPSCs were grown on three-dimensional-printed porous polylactic acid scaffolds for 7 days. After the predetermined time, samples were decellularized, and the remaining ECM detailed proteomic analysis was performed. Further, DPSC-secreated ECM impact to mesenchymal stromal cells (MSC) behaviour as well as its role in osteoregeneration induction were analysed.It was identified that DPSC-specific ECM protein network ornamenting surface-enhanced MSC attachment, migration and proliferation and even promoted spontaneous stem cell osteogenesis. This protein network also demonstrated angiogenic properties and did not stimulate MSCs to secrete molecules associated with scaffold rejection. With regard to bone defects, DPSC-derived ECM recruited endogenous stem cells, initiating the bone self-healing process. Thus, the DPSC-secreted ECM network was able to significantly enhance artificial bone construct integration and induce successful tissue regeneration.DPSC-derived ECM can be a perfect tool for decoration of various biomaterials in the context of bone tissue engineering.

Background Curcumin, a natural polyphenolic substance, has been known for more than two millennia as having strong anti-inflammatory activity towards multiple ailments, including arthritis. The main drawback of curcumin is its poor solubility in water, which leads to low intestinal absorption and minimal bioavailability. In this study, we aimed to compare the anti-arthritic in vivo effect of different curcumin preparations – basic curcumin extract, micellar curcumin, curcumin mixture with piperine, and microencapsulated curcumin. Methods Arthritis was induced in Wistar rats by complete Freund’s adjuvant, and the severity of arthritis was evaluated daily using the arthritis score system. Curcumin preparations were given to animals per os daily for 20 consecutive days, starting at 6th day after arthritis induction. To determine the inflammatory background, pro-inflammatory cytokines were determined using the ELISA test. In addition, hematologic test, weight change, and limb swelling were tracked. Results Our results indicate that curcumin had a rather weak effect on arthritis progression in the Wistar rat model, microencapsulated curcumin effectively prevented the progression of arthritis – the disease stabilized after 10 days of supplementation. It also reduced the levels of immune cells (neutrophils and leukocytes), as well as pro-inflammatory cytokines – TNFα, IL-1, and IL-6, which levels were close to arthritis-free control. Other formulations of curcumin had lower or no effect on arthritis progression. Conclusion Our study shows that the same concentrations of curcumin had a distinctly expressed positive anti-inflammatory effect depending on the form of its delivery. Specifically, we found that microencapsulated curcumin had the most promising effect for treatment. Graphical abstract

Topography of the scaffold is one of the most important factors defining the quality of artificial bone. However, the production of precise micro- and nano-structured scaffolds, which is known to enhance osteogenic differentiation, is expensive and time-consuming. Meanwhile, little is known about macro-patterns (larger than cell diameter) effect on cell fate, while this kind of structures would significantly facilitate the manufacturing of artificial skeleton. Therefore, this research is focused on polylactic acid scaffold's macro-pattern impact on rat's dental pulp stem cells (DPSCs) morphology, proliferation, and osteogenic differentiation. For this study, two types of scaffolds were 3D printed: wavy and porous. Wavy scaffolds consisted of 188 μm wide joined threads, meaning that cells might have been curved on the filament as well as compressed in the groove. Porous scaffolds were designed to avoid groove formation and consisted of 500 μm threads, arranged in the woodpile manner, forming 300 μm diameter pores. We found that both macro-surfaces influenced DPSC morphology compared to control. As a consequence, enhanced DPSC proliferation and increased osteogenic differentiation potential was registered in cells grown on these scaffolds. Finally, our results showed that the construction of an artificial bone did not necessarily require the precise structuring of the scaffold, because both types of macro-topographic PLA scaffolds were sufficient enough to induce spontaneous DPSC osteogenic differentiation. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 174-186, 2019.

3D printing of polylactic acid (PLA) and hydroxyapatite (HA) or bioglass (BG) bioceramics composites is the most promising technique for artificial bone construction. However, HA and BG have different chemical composition as well as different bone regeneration inducing mechanisms. Thus, it is important to compare differentiation processes induced by 3D printed PLA + HA and PLA + BG scaffolds in order to evaluate the strongest osteoconductive and osteoinductive properties possessing bioceramics. In this study, we analysed porous PLA + HA (10%) and PLA + BG (10%) composites' effect on rat's dental pulp stem cells fate in vitro. Obtained results indicated, that PLA + BG scaffolds lead to weaker cell adhesion and proliferation than PLA + HA. Nevertheless, osteoinductive and other biofriendly properties were more pronounced by PLA + BG composites. Overall, the results showed a strong advantage of bioceramic BG against HA, thus, 3D printed PLA + BG composite scaffolds could be a perspective component for patient-specific, cheaper and faster artificial bone tissue production.

In complex clinical conditions when physiological bone regeneration is insufficient, there is a need to develop synthetic material-based scaffolds. The morphologic properties of porous scaffolds are of crucial importance. The dimensional accuracy of 3D printed scaffolds can be affected by a variety of factors.Three groups of 3D printed scaffolds were investigated: PLA1 (pure polylactic acid) printed with an FDM Ultimaker Original printer, PLA2 and composite PLA/hydroxyapatite (PLA/HAp) scaffolds printed with a Pharaoh XD 20. PLA/HAp filament was created with hot-melt extrusion (HME) equipment. The morphology of the prepared scaffolds was investigated with SEM, micro-CT and superimposition techniques, gravimetric and liquid displacement methods.Layer heights of PLA1 scaffolds varied the most. PLA1 scaffold volume statistically significantly differed from PLA2 (p 0.001) and PLA/HAp (p 0.01) groups. Filament composition had no effect on the volumes of the scaffolds printed with the Pharaoh XD 20 printer (p 0.05). The total porosity of printed PLA/HAp scaffolds deviated the least from the original STL model.This study showed that PLA/10% HAp filament fabricated with HME and printed with FFF 3D printer produced equal or even better accuracy of printed scaffolds than scaffolds printed with pure PLA filament. Further research is needed to analyze the effect of HAp on 3D scaffold morphology, accuracy, mechanical and biologic properties.

Dental implant abutment and prosthetic materials, their surface treatment, and cleaning modalities are important factors for the formation of a peri-implant soft tissue seal and long-term stability of bone around the implant. This study aimed to investigate the influence of a polymeric material surface cleaning method on the surface roughness, water contact angle, and human gingival fibroblasts (HGF) proliferation. Polymeric materials tested: two types of milled polymethylmethacrylate (PMMA-Ker and PMMA-Bre), three-dimensionally (3D) printed polymethylmethacrylate (PMMA-3D), polyetheretherketone (PEEK), and polyetherketoneketone (PEKK). Titanium (Ti) and zirconia oxide ceramics (ZrO-HT) were used as positive controls. A conventional surface cleaning protocol (CCP) was compared to a multi-step research cleaning method (RCP). Application of the RCP method allowed to reduce Sa values in all groups from 0.14&ndash, 0.28 &micro, m to 0.08&ndash, 0.17 &micro, m (p &lt, 0.05 in PMMA-Ker and PEEK groups). Moreover, the water contact angle increased in all groups from 74&ndash, 91&deg, to 83&ndash, 101&deg, (p &lt, 0.05 in the PEKK group), except ZrO-HT&mdash, it was reduced from 98.7 &plusmn, 4.5&deg, to 69.9 &plusmn, 6.4&deg, 0.05). CCP resulted in higher variability of HGF viability after 48 and 72 h. RCP application led to higher HGF viability in PMMA-3D and PEKK groups after 48 h, but lower for the PMMA-Ker group (p &lt, 0.05). After 72 h, no significant differences in HGF viability between both cleaning methods were observed. It can be concluded that the cleaning method of the polymeric materials affected surface roughness, contact angle, and HGF viability at 48 h.

Topography of the scaffold is one of the most important factors defining the quality of artificial bone. However, the production of precise micro- and nano-structured scaffolds, which is known to enhance osteogenic differentiation, is expensive and time-consuming. Meanwhile, little is known about macro-patterns (larger than cell diameter) effect on cell fate, while this kind of structures would significantly facilitate the manufacturing of artificial skeleton. Therefore, this research is focused on polylactic acid scaffold's macro-pattern impact on rat's dental pulp stem cells (DPSCs) morphology, proliferation, and osteogenic differentiation. For this study, two types of scaffolds were 3D printed: wavy and porous. Wavy scaffolds consisted of 188 μm wide joined threads, meaning that cells might have been curved on the filament as well as compressed in the groove. Porous scaffolds were designed to avoid groove formation and consisted of 500 μm threads, arranged in the woodpile manner, forming 300 μm diameter pores. We found that both macro-surfaces influenced DPSC morphology compared to control. As a consequence, enhanced DPSC proliferation and increased osteogenic differentiation potential was registered in cells grown on these scaffolds. Finally, our results showed that the construction of an artificial bone did not necessarily require the precise structuring of the scaffold, because both types of macro-topographic PLA scaffolds were sufficient enough to induce spontaneous DPSC osteogenic differentiation. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 174-186, 2019.

The study aimed to 1) evaluate the cytotoxicity of luting cements: Hoffmann's Zinc Phosphate (Hoffmann's ZP), GC Fuji Plus Resin Modified Glass Ionomer (Fuji Plus RMGI) and 3M ESPE RelyX Unicem Resin Cement (RelyX Unicem RC) and 2) test if pre-washing reduces the cements' cytotoxicity. In vitro human gingival fibroblast (HGF) culture model was chosen. The cytotoxicity was evaluated by MTT test, the cell viability -by staining the cells with AO/EB dye mixture. The means±SD of Cell Survival Ratio (CSR%) were compared among different cement types under two testing conditions, with or without cement pre-washing. The CSR%s were compared by ANOVA and linear multiple regression (LMR). Hoffmann's ZPC was less cytotoxic, while Fuji Plus RMGIC and RelyX Unicem RC were more cytotoxic (ANOVA, p

Improvement in the yield of adult organism stem cells, and the ability to manage their differentiation and survival potential are the major goals in their application in regenerative medicine and in the adult stem cell research. We have demonstrated that adult rabbit muscle-derived cell lines with an unlimited proliferative potential in vitro can differentiate into myogenic, osteogenic, adipogenic and neurogenic lineages. Studies of cell survival in vitro showed that differentiated cells, except neurogenic ones, are more resistant to apoptosis inducers compared to proliferating cells. Resistance to death signals correlated with the level of protein kinase AKT phosphorylation. Skeletal muscle-derived cell lines can be multipurpose tools in therapy. Enhanced resistance of differentiated cells to certain types of damage shows their potential for long-term survival and maintenance in an organism. This article was published online on 29 January 2013. An error was subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected 6 March 2013.

Films and microstructured scaffolds have been fabricated using direct laser writing out of different polymers: hybrid organic-inorganic ORMOCORE b59, acrylate-based AKRE23, novel organic-inorganic Zr containing hybrid SZ2080, and biodegradable PEG-DA-258. Adult myogenic stem cells were grown on these surfaces in vitro. Their adhesion, growth, and viability test results suggest good potential applicability of the materials in biomedical practice. Pieces of these polymers were implanted in rat’s paravertebral back tissue. Histological examination of the implants and surrounding tissue ex vivo after 3 weeks of implantation was conducted and results show the materials to be at least as biocompatible as surgical clips or sutures. The applied direct laser writing technique seems to offer good future prospects in a polymeric 3D scaffold design for artificial tissue engineering with autologous stem cells.

Apoptosis in heart failure has been intensively investigated in vitro and in vivo. Stem cells have therapeutic value in the direct treatment of diseases, including cardiovascular disease. The main drawback of stem cell therapy is their poor survival in the diseased tissues. Since intracellular mitogen-activated protein kinases (MAPKs) actively participate in the regulation of cell survival and of proapoptotic signals, the ability to manipulate the mechanisms of MAPKs activation in myogenic stem cells might increase the survival of transplanted stem cells. Our results clearly demonstrate sustained activation of all three MAPKs, ERK, JNK and p38 in myogenic stem cells after exposure to the NO inducer, NOC-18. Inhibition of MAPKs phosphorylation by specific inhibitors revealed the anti-apoptotic role of MAPKs in myogenic stem cells.

Deoxynivalenol (DON) is a mycotoxin produced by what are thought to be the most prevalent toxin-producing fungi of the Fusarium genus. Here, we present the results of apoptosis induction, phosphorylation of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinases (MAPKs), and expression of the c-Jun protein after DON treatment, in a pre-B lymphocyte REH cell line. In addition, human pre-T lymphocyte Jurkat, hamster kidney-derived BHK21 and mouse hepatoma MH-22a cells were used in comparative experiments in vitro. We found that the DON effect was cell origin-dependent and dose-dependent, with a significant slow-down of cell proliferation and increase of apoptotic cells in blood cell lines. BHK21 and MH-22a cells were less sensitive to the DON effect. In blood-derived REH and Jurkat cells, DON-induced apoptotic changes were preceded by an increase in JNK and p38 MAPKs phosphorylation, as well as in c-Jun expression. However, the activation of JNK phosphorylation and c-Jun expression were transient, but did not coincide with each other. An inhibitor of JNK1/2, SP600125, had a negligible negative effect on REH cell viability after DON treatment, demonstrating that JNK does not contribute to DON-induced apoptosis. In contrast, studies on the role of p38 MAPK revealed that p38 signalling is required for DON-induced apoptosis in REH cells.

The study aimed to 1) evaluate the cytotoxicity of luting cements: Hoffmann's Zinc Phosphate (Hoffmann's ZP), GC Fuji Plus Resin Modified Glass Ionomer (Fuji Plus RMGI) and 3M ESPE RelyX Unicem Resin Cement (RelyX Unicem RC) and 2) test if pre-washing reduces the cements' cytotoxicity. In vitro human gingival fibroblast (HGF) culture model was chosen. The cytotoxicity was evaluated by MTT test, the cell viability -by staining the cells with AO/EB dye mixture. The means±SD of Cell Survival Ratio (CSR%) were compared among different cement types under two testing conditions, with or without cement pre-washing. The CSR%s were compared by ANOVA and linear multiple regression (LMR). Hoffmann's ZPC was less cytotoxic, while Fuji Plus RMGIC and RelyX Unicem RC were more cytotoxic (ANOVA, p0.001). The type of cement and cement pre-washing jointly explained 90% of cell survival (LMR, p0.001, adjusted squared R=0.889). The commonly used luting cements such as Hoffmann's ZP, Fuji Plus RMGI and RelyX Unicem RC may have a cytotoxic potential.

This work presents the latest results on direct laser writing of polymeric materials for tissue engineering applications. A femtosecond Yb:KGW laser (300 fs, 200 kHz, 515 nm) was used as a light source for non-linear lithography. Fabrication was implemented in various photosensitive polymeric materials, such as: hybrid organic- inorganic sol-gel based on silicon-zirconium oxides, commercial ORMOCER® class photoresins. These materials were structured via multi-photon polymerization technique with submicron resolution. Porous three-dimensional scaffolds for artificial tissue engineering were fabricated with constructed system and were up to several millimeters in overall size with 10 to 100 μm internal pores. Biocompatibility of the used materials was tested in primary rabbit muscle-derived stem cell culture in vitro and using laboratory rats in vivo. This interdisciplinary study suggests that proposed technique and materials are suitable for tissue engineering applications. © 2012 Society of Photo-Optical Instru

Improvement in the yield of adult organism stem cells, and the ability to manage their differentiation and survival potential are the major goals in their application in regenerative medicine and in the adult stem cell research. We have demonstrated that adult rabbit muscle-derived cell lines with an unlimited proliferative potential in vitro can differentiate into myogenic, osteogenic, adipogenic and neurogenic lineages. Studies of cell survival in vitro showed that differentiated cells, except neurogenic ones, are more resistant to apoptosis inducers compared to proliferating cells. Resistance to death signals correlated with the level of protein kinase AKT phosphorylation. Skeletal muscle-derived cell lines can be multipurpose tools in therapy. Enhanced resistance of differentiated cells to certain types of damage shows their potential for long-term survival and maintenance in an organism. This article was published online on 29 January 2013. An error was subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected 6 March 2013.

In this work, a combination of Direct Laser Writing (DLW), PoliDiMethylSiloxane (PDMS) soft lithography and UV lithography was used to create cm- scale microstructured polymer scaolds for cell culture experiments out of dierent biocompatible materials: novel hybrid organic-inorganic SZ2080, PDMS elastomer, biodegradable PEG- DA-258 and SU-8. Rabbit muscle-derived stem cells were seeded on the fabricated dierent periodicity scaolds to evaluate if the relief surface had any eect on cell proliferation. An array of microlenses was fabricated using DLW out of SZ2080 and replicated in PDMS and PEG-DA-258, showing good potential applicability of the used techniques in many other elds like micro- and nano- uidics, photonics, and MicroElectroMechanical Systems (MEMS). The synergetic employment of three dierent fabrication techniques allowed to produce desired objects with low cost, high throughput and precision as well as use materials that are dicult to process by other means (PDMS and PEG-DA-258). DLW is a relatively slow fabrication method, since the object has to be written point-by-point. By applying PDMS soft lithography, we were enabled to replicate laser-fabricated scaolds for stem cell growth and micro-optical elements for lab-on-a-chip applications with high speed, low cost and good reproducible quality.

Fabrication of scaffolds for cell growth with appropriate mechanical characteristics is top-most important for successful creation of tissue. Due to ability of fast fabrication of periodic structures with a different period, the holographic lithography technique is a suitable tool for scaffolds fabrication. The scaffolds fabricated by holographic lithography can be used in various biomedical investigations such as the cellular adhesion, proliferation and viability. These investigations allow selection of the suitable material and geometry of scaffolds which can be used in creation of tissue. Scaffolds fabricated from di-acrylated poly(ethylene glycol) (PEG-DA-258) over a large area by holographic lithography technique are presented in this paper. The PEG-DA scaffolds fabricated by holographic lithography showed good cytocompatibility for rabbit myogenic stem cells. It was observed that adult rabbit muscle-derived myogenic stem cells grew onto PEG-DA scaffolds. They were attached to the pillars and formed cell-cell interactions. It demonstrates that the fabricated structures have potential to be an interconnection channel network for cell-to-cell interactions, flow transport of nutrients and metabolic waste as well as vascular capillary ingrowth. These results are encouraging for further development of holographic lithography by improving its efficiency for microstructuring three-dimensional scaffolds out of biodegradable hydrogels

To assess qualitative and quantitative cytotoxicity effect on permanent prosthetic materials to human gingival fibroblasts.Human gingival tissues were collected (with informed consent) from patients undergoing periodontal surgical procedures and fibroblasts were cultured in vitro. Cell type was determined by performing proteomic analysis. Selected prosthetic materials including titanium, feldspathic ceramic, gold and chrome-cobalt alloy specimens (5×2 mm) were fabricated. The toxicity of prepared specimens was tested by exposing them to cell culture medium for 48, 72, 96 and 120 hours at 37°C under sterile conditions. Cell viability was estimated using MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay. The data concerning cell viability were statistically analyzed using two-way ANOVA test and Tukey multiple comparison test.Results obtained after 48 hours showed no toxic effect of titanium compared to control group. Cytotoxic effect was observed in gold alloy and feldspathic ceramic, however, it was not significant compared to control group. Chrome-cobalt alloy significantly reduced cell viability compared to control group (p≤0.001). Cytotoxicity diminished with increasing incubation time of specimens. After 120 hours of incubation all tested materials, except chrome-cobalt alloy, had no cytotoxicity.Titanium proved to be non-toxic. Gold alloy and feldspathic ceramic had short-term cytotoxic effect. Chrome-cobalt alloy had highest cytotoxic effect on fibroblast cells.

A tightly focused ultrafast pulsed laser beam is guided into the volume of the photosensitive material and induces nonlinear photomodification. By translating the sample, the position of the focus is changed relatively, thus point-by-point complex 3D structures can be written inside the bulk. In this report, we present a Laser Two-Photon Polymerization (LTPP) setup for three-dimensional micro/nanostructuring for applications in photonics, microoptics, micromechanics, microfluidics and biomedicine. This system enables fabrication of functional devices over a large area (up to several cm in lateral size) with reproducible sub-micrometer resolution (up to 200 nm). In our experiments a Yb:KGW active media laser oscillator (75 fs, 200 kW, 515 nm frequency doubled, 80 MHz) was used as an irradiation source. The sample was mounted on XYZ wide range linear motor driven positioning stages having 10 nm positioning resolution. These stages enable an overall travelling range of 100 mm into X and Y directions and 50 mm in Z direction and support a linear scanning speed of up to 300 mm/s. Control of all the equipment was automated via custom made computer software "3D-Poli" specially designed for LTPP applications. The model of the structure can be imported as CAD file, this enables rapid and flexible structuring out of various photopolymers like ORMOCERs, ORMOSILs, acrylates and PEGDAs which are commonly used in conventional UV mask, nanoimprint and μ-stereolithographies. In this paper, we demonstrate polymeric microstructures fabricated over a large area on glass, plastic and metal substrates. This opens a way to produce functional devices like photonic crystals, microlenses, micromechanic and microfluidic components and artificial scaffolds as templates for cell growth. Additionally, results of primary myogenic stem cells expanding on microfabricated polymeric scaffolds are provided. Cell proliferation tests show the material and structure to be biocompatible for the biomedical practice.

2,3-Dihydro-1H-1,5-benzodiazepine amidines were prepared by nucleophilic substitution of 2,3,4,5-tetrahydro-1H-1,5-benzodiazepine-2-thiones. Evaluation of the 13 synthesised amidines as antitumour agents was carried out in vitro against 60 human tumour cell lines at the National Cancer Institute, Bethesda, USA. The screening revealed a moderate cell growth inhibition of two derivatives on all cell lines at concentrations ranging from 10(-5) to 10(-4) mol/l. Log P values were theoretically calculated. The more active derivatives were found to exhibit a higher lipophilicity.

Summary form only given. We present direct laser fabrication of 3D microstructured scaffolds consisting out of a few polymeric materials owning different biological properties. Direct laser writing in photo/thermo-sensitive materials using ultra short light pulses of high repetition laser provides unmatched flexibility in controllable 3D microstructuring in a variety of bio-materials [1], as well as manufacturing throughput empowers overall structure size of more than 1 mm3, making it an attractive method to fabricate scaffolds for cell studies and tissue engineering applications [2, 3]. In this work, a femtosecond direct laser writing system was supplemented by a machine vision [4] to relocate the sample between different fabrication steps.