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Malwina Sosnowska,1 Marta Kutwin,1 Sławomir Jaworski,1 Barbara Strojny,1 Mateusz Wierzbicki,1 Jarosław Szczepaniak,1 Maciej Łojkowski,2 Wojciech Święszkowski,2 Jaśmina Bałaban,1 André Chwalibog,3 Ewa Sawosz11Department of Animal Nutrition and Biotechnology, Warsaw University of Life Sciences, Warsaw 02-786, Poland; 2Faculty of Materials Science and Engineering, Warsaw University of Technology, Warsaw 00-661, Poland; 3Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg 1870, DenmarkIntroduction and objective: Degradation of the extracellular matrix (ECM) changes the physicochemical properties and dysregulates ECM–cell interactions, leading to several pathological conditions, such as invasive cancer. Carbon nanofilm, as a biocompatible and easy to functionalize material, could be used to mimic ECM structures, changing cancer cell behavior to perform like normal cells.Methods: Experiments were performed in vitro with HS-5 cells (as a control) and HepG2 and C3A cancer cells. An aqueous solution of fullerene C60 was used to form a nanofilm. The morphological properties of cells cultivated on C60 nanofilms were evaluated with light, confocal, electron and atomic force microscopy. The cell viability and proliferation were measured by XTT and BrdU assays. Immunoblotting and flow cytometry were used to evaluate the expression level of proliferating cell nuclear antigen and determine the number of cells in the G2/M phase.Results: All cell lines were spread on C60 nanofilms, showing a high affinity to the nanofilm surface. We found that C60 nanofilm mimicked the niche/ECM of cells, was biocompatible and non-toxic, but the mechanical signal from C60 nanofilm created an environment that affected the cell cycle and reduced cell proliferation.Conclusion: The results indicate that C60 nanofilms might be a suitable, substitute component for the niche of cancer cells. The incorporation of fullerene C60 in the ECM/niche may be an alternative treatment for hepatocellular carcinoma.Keywords: liver cancer cells, fullerene, extracellular matrix, adhesion, cell cycle

Magnesium (Mg) alloys are used as biomaterials because of their biocompatibility and stiffness which is similar to that of human bone tissue. This reduces the stress shielding complications associated with bone resorption. Mg is one of the fundamental divalent ions that have an effect on bone-forming cells and also plays an important role in bone metabolism. This is supported by the results of in vivo studies, which indicate that Mg degradation does not damage surrounding tissue and promotes bone remodelling [1]. One of the main drawbacks limiting the wide use of Mg alloys in biomedicine is their low corrosion resistance, and associated high hydrogen release in the surrounding environment which causes pain in the area of implant placement [1-3]. Additive manufacturing is an attractive alternative to conventional manufacturing of Mg alloys, and researchers have so far studied the properties of the following Mg-based alloys:Mg-Al-Zn, Mg-Zn-Zr, and REE-containing alloys [4]. In this research, we propose to develop degradation of Mg-based alloys enriched with Li and Ca which will decrease the density of the alloys and simultaneously improve mechanical properties of the alloys. It is expected to create refined microstructure which should lead to the lowering of the intensity of the occurring corrosion mechanisms. We decided to focused on the Mg-4Li-0.5Ca with single a (Mg) phase. As a reference cast material with the same composition was used. Micro-computed tomography was used to check the porosity of the materials produced. The microstructure of alloys was analyzed through electron back scattered diffraction and phase composition was analyzed using X-ray. Corrosion resistance of both alloys were performed using various electrochemical techniques in phosphate-buffered saline solution (PBS). The materials corrosion rate was investigated by hydrogen evolution tests, and corroded specimens were characterized by SEM and optical profilometer. [ABSTRACT FROM AUTHOR]

Tissue engineering combines artificial scaffolds and living cells in order to reconstruct damaged tissues and organs. The biodegradable scaffolds should maintain their mechanical properties during first stages of the regeneration. The aim of this study was to investigate the extent the degradation affects the mechanical stability of novel biodegradable composite scaffolds in relation to their composition. The scaffolds were made using fused deposition modeling. They were composed of ternary composites containing poly( ε-caprolactone) (PCL), 5 wt% of tricalcium phosphate (TCP) and 5, 15, and 25 wt% of poly(lactide- co-glycolide) (PLGA). Scaffolds made of pristine PCL and binary composite PCL-TCP were tested as reference samples. The degradation experiment was carried out in simulated body fluid at 37°C for 12 weeks. Mechanical tests were carried out in a mechanical tester. Strain was measured using digital image correlation and crossbar displacement. Chemical composition had a significant effect on initial mechanical properties and their changes during degradation. The initial apparent Young's modulus of ternary composite scaffolds was two times higher than that of PCL-TCP. Higher PLGA concentration yielded faster decrease of the mechanical properties. At the end of the experiment, there were no significant differences of the modulus among all tested materials although degradation of the ternary composite scaffolds was significantly advanced. POLYM. COMPOS., 38:2402-2410, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Magnesium (Mg) alloys are used as biomaterials because of their biocompatibility and stiffness which is similar to that of human bone tissue. This reduces the stress shielding complications associated with bone resorption. Mg is one of the fundamental divalent ions that have an effect on bone-forming cells and also plays an important role in bone metabolism. This is supported by the results of in vivo studies, which indicate that Mg degradation does not damage surrounding tissue and promotes bone remodelling [ref]. One of the main drawbacks limiting the wide use of Mg alloys in biomedicine is their low corrosion resistance, and associated high hydrogen release in the surrounding environment which causes pain in the area of implant placement [1-3]. Additive manufacturing is an attractive alternative to conventional manufacturing of Mg alloys, and researchers have so far studied the properties of the following Mg-based alloys: Mg-Al-Zn, Mg-Zn-Zr, and REE- containing alloys [4]. In this research, we propose to develop possibilities of fabrication of Mg-based alloys enriched with Li and Ca which will decrease the density of the alloys and simultaneously improve mechanical properties of the alloys. It is expected to create ultra-refined microstructure which should lead to the lowering of the intensity of the occurring corrosion mechanisms. We decided to work on the Mg-4Li- 0.5.a and Mg-8Li-0.5Ca compositions. As a reference cast materials with the same composition were used. The microstructure of alloys was analyzed through electron back scattered diffraction and phase composition was analyzed using X-ray. Corrosion resistance of both alloys were performed using various electrochemical techniques in phosphate-buffered saline solution (PBS). The materials corrosion rate was investigated by hydrogen evolution tests, and corroded specimens were characterized by SEM and optical profilometer observations. Our results show that ultrafine grained microstructure was formed in Mg-4Li-Ca and Mg-8Li-Ca. It should be the main reason of the corrosion resistance improvement. [ABSTRACT FROM AUTHOR]

Poly(ε-caprolactone), PCL, is of great interest for fabrication of biodegradable scaffolds due to its high compatibility with various manufacturing techniques, especially Fused Deposition Modeling (FDM). However, slow degradation and low strength make application of PCL limited only to longer-term bioresorbable and non-load bearing implants. To overcome latter drawbacks, ternary PCL-based composite fibrous scaffolds consisting of 70-95 wt % PCL, 5 wt % Tricalcium Phosphate (TCP) and 0-25 wt % poly(lactide- co-glycolide) (PLGA) were fabricated using FDM. In the present study, the effect of composition of the scaffolds on their mechanical properties, degradation kinetics, and surface properties (wettability, surface energy, and roughness) was investigated and correlated with response of human bone marrow mesenchymal stromal cells (HBMC). The presence of PLGA increased degradation kinetics, surface roughness and significantly improved scaffold colonization. Of the evaluated surface properties only the wettability was correlated with the surface area colonized by HBMC. This study demonstrates that introduction of PLGA into PCL-TCP binary composite could largely abolish the disadvantages of the PCL matrix and improve biocompatibility by increasing wettability and polar interactions rather than surface roughness. Additionally, we showed great potential of multicellular spheroids as a sensitive in vitro tool for detection of differences in chemistry of 3D scaffolds. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103: 2394-2404, 2015. [ABSTRACT FROM AUTHOR]

An optimal method for composites preparation as an input to rapid prototyping fabrication of scaffolds with potential application in osteochondral tissue engineering is still needed. Scaffolds in tissue engineering applications play a role of constructs providing appropriate mechanical support with defined porosity to assist regeneration of tissue. The aim of the presented study was to analyze the influence of composite fabrication methods on scaffolds mechanical properties. The evaluation was performed on polycaprolactone (PCL) with 5 wt% beta-tricalcium phosphate (TCP) scaffolds fabricated using fused deposition modeling (FDM). Three different methods of PCL-TCP composite preparation: solution casting, particles milling, extrusion and injection were used to provide material for scaffold fabrication. The obtained scaffolds were investigated by means of scanning electron microscope, x-ray micro computed tomography, thermal gravimetric analysis and static material testing machine. All of the scaffolds had the same geometry (cylinder, 4×6 mm) and fiber orientation (0/60/120°). There were some differences in the TCP distribution and formation of the ceramic agglomerates in the scaffolds. They depended on fabrication method. The use of composites prepared by solution casting method resulted in scaffolds with the best combination of compressive strength (5.7±0.2 MPa) and porosity (48.5±2.7 %), both within the range of trabecular bone.

Postępująca inwazja bakteryjna w tkankach zęba prowadzi do zapalenia miazgi, powstawania w niej mikroropnii, zniszczenia a w konsekwencji do zapalenia ozębnej. Z tego względu celem leczenia endodontycznego stało się trójwymiarowe oczyszczenie kanału korzeniowego od jego ujścia do przewężenia fizjologicznego. Dlatego celem pracy jest analiza konfiguracji, ilości kanałów korzeniowych, istnienia kanałów bocznych oraz delty korzeniowej w grupie pierwszych zębów trzonowych stałych w uzębieniu ludzkim. Jednocześnie ocenie poddawana jest dodatkowo swoistość badania radiologicznego (zdjęcia zębowe), poprzez porównanie zdjęć rentgenowskich wykonanych przed preparacją zębów z obrazem systemu kanałowego uzyskanego na podstawie mikrotomografii oraz po wykonaniu szlifów poprzecznych i ich obserwacji na mikroskopie świetlnym. Celem tej oceny jest zaprezentowanie rozbieżności pomiędzy oceną radiologiczną systemu kanałowego a kliniczną.

Dariusz Smolen1, Tadeusz Chudoba1, Iwona Malka1, Aleksandra Kedzierska1, Witold Lojkowski1, Wojciech Swieszkowski2, Krzysztof Jan Kurzydlowski2, Malgorzata Kolodziejczyk-Mierzynska3, Malgorzata Lewandowska-Szumiel31Polish Academy of Science, Institute of High Pressure Physics, Warsaw, Poland; 2Faculty of Materials Engineering, Warsaw University of Technology, Warsaw, Poland; 3Department of Histology and Embryology, Center of Biostructure Research, Medical University of Warsaw, Warsaw, PolandAbstract: A microwave, solvothermal synthesis of highly biocompatible hydroxyapatite (HAp) nanopowder was developed. The process was conducted in a microwave radiation field having a high energy density of 5 W/mL and over a time less than 2 minutes. The sample measurements included: powder X-ray diffraction, density, specific surface area, and chemical composition. The morphology and structure were investigated by scanning electron microscopy as well as transmission electron microscopy (TEM). The thermal behavior analysis was conducted using a simultaneous thermal analysis technique coupled with quadruple mass spectrometry. Additionally, Fourier transform infrared spectroscopy tests of heated samples were performed. A degradation test and a biocompatibility study in vitro using human osteoblast cells were also conducted. The developed method enables the synthesis of pure, fully crystalline hexagonal HAp nanopowder with a specific surface area close to 240 m2/g and a Ca/P molar ratio equal to 1.57. TEM measurements showed that this method results in particles with an average grain size below 6 nm. A 28-day degradation test conducted according to the ISO standard indicated a 22% loss of initial weight and a calcium ion concentration at 200 µmol/dm3 in the tris(hydroxymethyl)aminomethane hydrochloride test solution. The cytocompatibility of the obtained material was confirmed in a culture of human bone derived cells, both in an indirect test using the material extract, and in direct contact. A quantitative analysis was based on the 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide. Viability assay as well as on DNA content measurements in the PicoGreen test. Indirect observations were performed at one point in time according to the ISO standard for in vitro cytotoxicity (ie, after 24 hours of cell exposure to the extracts). The direct contact tests were completed at three time points: after 24 hours, on day 7, and on day 14 of a culture in an osteogenic medium. All of the tests revealed good tolerance of cells toward the material; this was also shown by means of live/dead fluorescent staining. Both quantitative results and morphological observations revealed much better cell tolerance toward the obtained HAp compared to commercially available HAp NanoXIM, which was used as a reference material.Keywords: bone regeneration, bone substitute, microwave, HAp

The synergistic integration of microfluidic technologies with additive manufacturing systems is advancing the development of innovative platforms to 3D bioprint scaffolds for tissue engineering with unparalleled biological relevance. Significant interest is growing in realizing porous functionally graded materials (pFGMs) that can resemble the hierarchical organization of porosity found in bone tissue. This study introduces a method for fabricating porous scaffolds based on the real-time generation of a liquid foam, which is gelled, forming porous fibers that are organized into structured matrixes using a 3D bioprinting system. The primary advantage of this approach is the possibility to adjust bubble size during printing dynamically, modifying the characteristics of the deposited foamed filaments online and in one step. As a result, locally-defined and tailor-made pores can be distributed in 3D structures with high spatial accuracy. Besides the mechanical and morphological characterization of diverse microarchitectures, we also explored the biocompatibility of the proposed approach by directly embedding osteosarcoma cells within the biomaterial. Results demonstrated the biocompatibility of the proposed methodology and revealed the influence of the interior microporosity on cell proliferation, highlighting the potential for creating tailored tissue microenvironments. The findings underscore the versatility of the presented 3D bioprinting system and its potential in fabricating biomimetic scaffolds with tailored morphological gradients, representing a substantial advancement in pFGM synthesis, with direct implications in regenerative medicine and tissue engineering.

Limited data are available on the causes of hydrops fetalis in dogs. Congenital heart defects may be an important contributing factor. Standard autopsy often fails to provide a comprehensive and accurate diagnosis on very small hearts. This study was carried out on five French bulldog puppies all presenting with advanced hydrops fetalis and four diagnosed with pulmonary hypoplasia at autopsy. The body weight of the dogs ranged from 142 to 687 g and the heart with lungs weighed from 4.5 to 23.6 g. The hearts and pulmonary vessels were filled with barium contrast, and micro-CT scans of the physiologically connected heart and lungs were performed. In all five puppies, we confirmed congenital heart defects including: Puppy #1. Perimembranous ventricular septal defect and aortic dextroposition; Puppy #2. Interrupted aortic arch with aortic valve dysplasia and aortic stenosis; Puppy #3. Tricuspid valve dysplasia and bicuspid pulmonary trunk valve; Puppy #4. Aortic stenosis and ventricular septal defect; Puppy #5. Tricuspid valve dysplasia. Additionally, four puppies had pulmonary vascular hypoplasia. Contrast-enhanced micro-CT can provide highly accurate diagnosis of complex congenital heart and lung defects. Examination of the heart in conjunction with the lungs appears to be a rational approach in animals with hydrops fetalis., Competing Interests: Declarations. Competing interests: The authors declare no competing interests. Ethics declarations: All procedures were in line with Polish law regulations. Written permission for all examination was granted by participating owners. The study was carried out in accordance with the standards recommended by the EU Directive 2010/63/EU for animal experiments and Good Laboratory Practice and The Act of the Polish Parliament of 15 January 2015 on the Protection of Animals Used for Scientific or Educational Purposes (Journal of Laws 2015, item 266). According to Polish legal regulations (The Act of the Polish Parliament of 15 January 2015 on the Protection of Animals Used for Scientific or Educational Purposes, Journal of Laws 2015, item 266) no formal ethics consent was required for this study except for the informed consent of participants. Therefore, the written informed consent for participation in the study was obtained by us from all owners who decided to participate in the study. Not a single animal was euthanized for the purpose of the above study., (© 2025. The Author(s).)

Bone tissue regeneration can be affected by various architectonical features of 3D porous scaffold, for example, pore size and shape, strut size, curvature, or porosity. However, the design of additively manufactured structures studied so far was based on uniform geometrical figures and unit cell structures, which often do not resemble the natural architecture of cancellous bone. Therefore, the aim of this study was to investigate the effect of architectonical features of additively manufactured (aka 3D printed) titanium scaffolds designed based on microtomographic scans of fragments of human femurs of individuals of different ages on in vitro response of human bone-derived mesenchymal stem cells (hMSC). Four different types of titanium scaffold (33Y, 48Y, 56Y, and 63Y, where the number indicates the age of the individual) were fabricated using laser beam powder bed fusion (PBF-LB) and characterized with respect to the dimensional features, permeability, and stiffness. hMSC were seeded onto the scaffolds and MTS, DNA, alkaline phosphatase, and alizarin red assays were used to study cell viability, proliferation, and osteogenic differentiation. Microcomputed tomography revealed that the largest average pore size was in scaffolds 63Y (543 ± 200 μm), which was nearly twice as large as the smallest pores in scaffolds 56Y. Moreover, scaffolds 63Y exhibited the highest porosity (~61%), while the other architectures had porosity of ~43%-44%. Scaffolds 63Y also had the lowest surface area-to-volume ratio (11.07 ± 0.05 mm -1 ), whereas scaffolds 56Y had the highest (14.80 ± 0.06 mm -1 ). Furthermore, scaffolds 33Y had the largest strut size (398 ± 124 μm), exceeding the size in scaffolds 56Y (the smallest strut size) by over 1.5 times. CFD simulations indicated that the hydraulic permeability was the highest for scaffolds 63Y (5.24 × 10 -9  m 2 ; order of magnitude higher than in the other architectures). Stiffness of the investigated scaffolds, determined by finite element modeling, ranged from ~29 GPa (63Y) to ~60 GPa (56Y). This study demonstrates that the highest manufacturing accuracy in 3D printed structures based on architectural designs inspired by cancellous bone could be achieved when the structures were characterized by moderate strut sizes, the largest pores, and the highest porosity and permeability. The scaffold with the highest porosity and permeability (i.e., 63Y) yielded the lowest cell retention. Regarding the osteogenic differentiation, a correlation was found between the mineralization of the deposited extracellular matrix and the hydraulic permeability, pore size, and surface area-to-volume ratio but not the porosity., (© 2025 Wiley Periodicals LLC.)

In this study, the interaction of pure Mg and WE43 alloy under the presence of osteoblast (OB) and osteoclast (OC) cells and their influence on the degradation of materials have been deeply analyzed. Since OB and OC interaction has an important role in bone remodeling, we examined the surface morphology and dynamic changes in the chemical composition and thickness of the corrosion layers formed on pure Mg and WE43 alloy by direct monoculture and coculture of pre-differentiated OB and OC cells in vitro. Electrochemical techniques examined the corrosion performance. The corrosion products were characterized using a combination of the focused ion beam (FIB), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). Cell viability and morphology were assessed by fluorescent microscopy and SEM. Our findings demonstrate cell spread and attachment variations, which differ depending on the Mg substrates. It was clearly shown that cell culture groups delayed degradation processes with the lowest corrosion rate observed in the presence of OBOC coculture for the WE43 substrate. Ca-P enrichment was observed in the outer-middle region of the corrosion layer but only after 7 days of OBOC coculture on WE43 and after 14 days on the pure Mg specimens. STATEMENT OF SIGNIFICANCE: Magnesium metallic materials that can degrade over time provide distinct opportunities for orthopedic application. However, there is still a lack, especially in elucidating cell-material interface characterization. This study investigated the influence of osteoblast-osteoclast coculture in direct Mg-material contact. Our findings demonstrated that pre-differentiated osteoblasts and osteoclasts cocultured on Mg substrates influenced the chemistry of the corrosion layers. The cell spread and attachment were Mg substrate-dependent. The findings of coculturing bone cells directly on Mg materials within an in vitro model provide an effective approach for studying the dynamic degradation processes of Mg alloys while also elucidating cell behavior and their potential contribution to the degradation of these alloys., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)