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Rafał Pokrowiecki,1,2 Tomasz Zaręba,3 Barbara Szaraniec,4 Krzysztof Pałka,5 Agnieszka Mielczarek,6 Elżbieta Menaszek,7 Stefan Tyski3,8 1Center for Cranio-Maxillo-Facial Surgery, Voivodeship Children’s Hospital, Olsztyn, 2Department of Oral Surgery, Jagiellonian Medical University, Kraków, 3Department of Antibiotics and Microbiology, National Medicines Institute, Warsaw, 4Faculty of Material Science and Ceramics, AGH University of Science and Technology, Kraków, 5Department of Materials Engineering, Lublin University of Technology, Lublin, 6Department of Conservative Dentistry, Medical University of Warsaw, Warsaw, 7Department of Cytobiology, Collegium Medicum, Jagiellonian University, Kraków, 8Department of Pharmaceutical Microbiology, Medical University of Warsaw, Warsaw, Poland Abstract: The addition of an antibacterial agent to dental implants may provide the opportunity to decrease the percentage of implant failures due to peri-implantitis. For this purpose, in this study, the potential efficacy of nanosilver-doped titanium biomaterials was determined. Titanium disks were incorporated with silver nanoparticles over different time periods by Tollens reaction, which is considered to be an eco-friendly, cheap, and easy-to-perform method. The surface roughness, wettability, and silver release profile of each disc were measured. In addition, the antibacterial activity was also evaluated by using disk diffusion tests for bacteria frequently isolated from the peri-implant biofilm: Streptococcus mutans, Streptococcus mitis, Streptococcus oralis, Streptococcus sanguis, Porphyromonas gingivalis, Staphylococcus aureus, and Escherichia coli. Cytotoxicity was evaluated in vitro in a natural human osteoblasts cell culture. The addition of nanosilver significantly increased the surface roughness and decreased the wettability in a dose-dependent manner. These surfaces were significantly toxic to all the tested bacteria following a 48-hour exposure, regardless of silver doping duration. A concentration of 0.05 ppm was sufficient to inhibit Gram-positive and Gram-negative species, with the latter being significantly more susceptible to silver ions. However, after the exposure of human osteoblasts to 0.1 ppm of silver ions, a significant decrease in cell viability was observed by using ToxiLight™ BioAssay Kit after 72 hours. Data from the present study indicated that the incorporation of nanosilver may influence the surface properties that are important in the implant healing process. The presence of nanosilver on the titanium provides an antibacterial activity related to the bacteria involved in peri-implantitis. Finally, the potential toxicological considerations of nanosilver should further be investigated, as both the antibacterial and cytotoxic properties may be observed at similar concentration ranges. Keywords: biomaterials, dental plaque, peri-implantitis, peri implant mucositis, silver, nanotechnology, nanomedicine

In cat breeding, an important step is reproduction and obtaining healthy offspring. The main factor determining the survival of newborn kittens is the normal course and length of pregnancy. The purpose of this study was to determine the effect of gestation length on the early development of kittens. It was shown that kittens (premature kittens) later double their body weight (p <.01), have lower daily gains (p <.01) and higher body weight during eye‐opening (p <.01), which occurs later than in kittens born on time. In addition, due to a shorter period of prenatal development, they require more time until the day of eye‐opening, which, together with the length of pregnancy, was defined as development age. [ABSTRACT FROM AUTHOR]

The life expectancy of adult butterflies is highly diverse. Substantial variation may be found among closely related species, and even on the intraspecific level, where it could be associated with sex, genetic differentiation, diet and weather conditions. We compared the demographic parameters of populations of the regionally endangered Boloria eunomia butterfly living in two different habitats. Across its boreal‐mountane distribution range in Europe, B. eunomia occurs in two ecotypes associated with wet meadows and raised bogs using distinct both larval and nectar plants. We carried out simultaneous studies of both ecotypes through mark–recapture surveys of two large populations in NE Poland, located close to each other. A total number of 1124 and 644 individuals were marked at the bog and meadow sites respectively, and 51 and 33% of them were recaptured at least once. The estimated adult population size of the bog population (about 3000) was twice as large as that of the meadow population, which however was characterized by more than three‐fold higher density. The emergence of imagoes was highly synchronized, and protandry was evident. The sex ratio was slightly male‐biased and the mean capture probability was significantly higher for males. More importantly, the estimated life span of males was considerably shorter than that of females at each site. Finally, both sexes of the 'meadow' ecotype lived significantly longer than those from the raised bog. The detected pattern can be related to distinct larval food plants and/or nectar resources, different pressures from predators, genetic variation and morphological differences affecting thermal properties. Further investigations would be useful to reveal if the shorter adult life span translates into reduced viability of bog populations and consequently whether they are potentially more threatened, at least in the southern margins of the distribution range in Central Europe. We compared the demographic parameters of two local large populations of Boloria eunomia butterfly living in two different habitat through intensive mark–recapture surveys. We found out that (1) the sex ratio was slightly male‐biased and (2) the mean capture probability was significantly higher for males but (3) the estimated life span of males was considerably shorter than that of females at each site. However, (4) both sexes of the 'meadow' ecotype lived significantly longer than those from the raised bog. The detected pattern can be related to distinct larval food plants and/or nectar resources, different pressures from predators, genetic variation and morphological differences affecting thermal properties. [ABSTRACT FROM AUTHOR]

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Dental composites are gaining great popularity in restorative dentistry because of their aesthetic appeal and capacity to replicate the natural color of teeth. Nevertheless, their lifespan and durability rely on various factors, such as the polishing technique and the environmental conditions they are exposed to. The study aimed to assess the influence of the method of final polishing of dental composite on the surface roughness and microhardness of materials also considering the environment of different pHs. Disc-shaped samples (5 mm diameter and 2 mm thickness) have been prepared for microhardness and roughness tests from two dental composites: A2 Clearfil Majesty ES 2 Classic and A2D Clearfil Majesty Premium. One-third of samples were polished with polishing discs, OptiDisc, another one-third of samples were polished with Eve Diacomp Twist rubbers and polishing brush with diamond particles, and rest of the samples were stored without any polishing (the control group). Tested materials were incubated in distilled water or acidic buffer (pH = 2) for 3 weeks at a temperature of 37 °C. No statistically significant differences were found for roughness for the two materials tested after incubation in liquids. A decrease in Vicker microhardness was found for Clearfil Majesty ES 2 Classic after soaking in a low pH liquid, and no such relationship was found for Clearfil Majesty Premium. The improved resistance of these materials to the negative oral environment may result in the longer survival of composite restorations in patients with poor diet or diseases, causing a decrease in oral pH.

Injuries to the articular cartilage of the human knee joint, commonly resulting from trauma, inflammation, or age- and activity-related wear and tear, have significant implications, primarily leading to osteoarthritis (OA). Conservative treatments for such injuries often yield suboptimal clinical outcomes. Surgical interventions using current methods may not consistently provide satisfactory results, largely due to the formation of low-quality scar tissue lacking the biomechanical properties of hyaline cartilage. In this retrospective study, we compared the results of two promising methods for regenerating cartilage defects in the knee joints using scaffolds soaked with stem cells of different origins: bone marrow aspirate concentrate mesenchymal stem cells (BMAC-MSCs) and human umbilical cord-derived mesenchymal stem cells (hUCB-MSCs). We evaluated 39 patients (39 knees, hUCB-MSCs: 20 knees, BMAC: 19 knees) at the 12-month follow-up using VAS, KOOS, Lysholm scales and radiologically with M-MOCART 2.0 score. The analysis demonstrated substantial overall improvement in both groups, notably reflected in enhanced quality of life for the patients. Interestingly, the final scores in the hUCB-MSCs group were comparable to those in the BMAC-MSCs group, with no statistically significant differences observed, despite variations in preoperative age and lesion size. Notably, the hUCB-MSCs group consisted of significantly older individuals with larger lesion sizes. Both procedures were found to be safe, and improvement was observed in both groups, which holds promise for future clinical investigations.

Whey protein isolate (WPI) hydrogels are attractive biomaterials for application in bone repair and regeneration. However, their main limitation is low mechanical strength. Therefore, to improve these properties, the incorporation of ceramic phases into hydrogel matrices is currently being performed. In this study, novel whey protein isolate/calcium silicate (WPI/CaSiO 3 ) hydrogel biomaterials were prepared with varying concentrations of a ceramic phase (CaSiO 3 ). The aim of this study was to investigate the effect of the introduction of CaSiO 3 to a WPI hydrogel matrix on its physicochemical, mechanical, and biological properties. Our Fourier Transform Infrared Spectroscopy results showed that CaSiO 3 was successfully incorporated into the WPI hydrogel matrix to create composite biomaterials. Swelling tests indicated that the addition of 5% ( w / v ) CaSiO 3 caused greater swelling compared to biomaterials without CaSiO 3 and ultimate compressive strength and strain at break. Cell culture experiments demonstrated that WPI hydrogel biomaterials enriched with CaSiO 3 demonstrated superior cytocompatibility in vitro compared to the control hydrogel biomaterials without CaSiO 3 . Thus, this study revealed that the addition of CaSiO 3 to WPI-based hydrogel biomaterials renders them more promising for bone tissue engineering applications.

Halogenated, labeled with deuterium, tritium or doubly labeled with deuterium and tritium in the 3S position of the side chain isotopomers of L-phenylalanine and phenylpyruvic acid were synthesized. Isotopomers of halogenated L-phenylalanine were obtained by addition of ammonia from isotopically enriched buffer solution to the halogenated derivative of (E)-cinnamic acid catalyzed by phenylalanine ammonia lyase. Isotopomers of halogenated phenylpyruvic acid were obtained enzymatically by conversion of the appropriate isotopomer of halogenated L-phenylalanine in the presence of phenylalanine dehydrogenase. As a source of deuterium was used deuterated water, as a source of tritium was used a solution of highly diluted tritiated water. The labeling takes place in good yields and with high deuterium atom% abundance., (© 2023 John Wiley & Sons Ltd.)

Fracture toughness is one of the main factors influencing the durability of light-cured composites used for dental restorations and fillings. One of the methods of increasing the fracture toughness is the modification of the matrix with liquid acrylonitrile-free liquid rubber. This study aimed to assess the miscibility of acrylonitrile-free liquid rubber with a blend of resins and their stability over time, and to determine the optimal amount of liquid rubber (LR) in the blend due to mechanical properties. Two blends of dimethacrylate resins were used: resin "F" composed of BisGMA (60 wt.%), TEGDMA (20 wt.%), BisEMA (10 wt.%) and UDMA (10 wt.%), and "C" resin containing BisGMA (40 wt.%), TEGDMA (40 wt.%), BisEMA (10 wt.%) and UDMA (10 wt.%). The modifier Hypro ® 2000X168LC VTB liquid rubber was used in at 1%, 2%, 3%, 4%, 5%, 10%, 15% and 20% by weight in the resin blend. The miscibility was assessed by microscopy. The fracture toughness, flexural strength and Young's modulus were determined in the bending test. The results showed that the solubility of the liquid rubber depends on the ratio of BisGMA/TEGDMA in the resins. In resins with 40 wt.% TEGDMA, the LR solubility was as high as 5%, while resins with 20 wt.% TEGDMA, the liquid rubber did not dissolve. The LR-resin mixtures showed good time stability, and no changes in the size or morphology of the rubber domains were found after 24 h of mixing. The maximum fracture toughness (2.46 MPa m 1/2 ) was obtained for 5 wt.% LR in resin F and for 15 wt.% LR in resin C (2.53 MPa m 1/2 ). The modification with liquid rubber resulted in an exponential reduction in both flexural strength and Young's modulus. The analysis of the results of the mechanical tests allowed us to determine the optimal amount of LR for both resins. For resin F it was 5.4 wt.%, and for resin C it was 8.3 wt.%. It can be stated that the optimal amount of liquid rubber increases with its solubility in the resin.

Hydroxyapatites of high calcium and phosphate ions adsorption capacity are highly bioactive. However, they cause the removal of these ions from tissue liquids and cell culture media, thus reducing viability and proliferation potential of osteoblasts. Addition of small amount of gypsum (calcium sulfate dihydrate) to such hydroxyapatite-based composites may help to compensate the ions removal and stimulate the osteoblasts growth and proliferation. Therefore, the aim of this work was to enrich the highly porous hydroxyapatite-based composite with gypsum and verify its effect on ions adsorption as well as osteoblasts viability and proliferation. The results showed that addition of 1.5-1.75% gypsum caused short-term calcium ions compensation in media incubated with the composite and time-shifted increase of osteoblasts proliferation. Moreover, presence of gypsum in the composite increased the content of large pores in SBF-incubated biomaterials with no effect on their microstructure or mechanical parameters. Overall, gypsum addition improves the compatibility of hydroxyapatite-based materials with no critical disadvantages for other properties., 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 © 2022 Elsevier B.V. All rights reserved.)

The aim of this study was to evaluate the effect of modification with liquid rubber on the adhesion to tooth tissues (enamel, dentin), wettability and ability to inhibit bacterial biofilm formation of resin-based dental composites. Two commercial composites (Flow-Art-flow type with 60% ceramic filler and Boston-packable type with 78% ceramic filler; both from Arkona Laboratorium Farmakologii Stomatologicznej, Nasutów, Poland) were modified by addition of 5% by weight (of resin) of a liquid methacrylate-terminated polybutadiene. Results showed that modification of the flow type composite significantly ( p < 0.05) increased the shear bond strength values by 17% for enamel and by 33% for dentine. Addition of liquid rubber significantly ( p < 0.05) reduced also hydrophilicity of the dental materials since the water contact angle was increased from 81-83° to 87-89°. Interestingly, modified packable type material showed improved antibiofilm activity against Steptococcus mutans and Streptococcus sanguinis (quantitative assay with crystal violet), but also cytotoxicity against eukaryotic cells since cell viability was reduced to 37% as proven in a direct-contact WST-8 test. Introduction of the same modification to the flow type material significantly improved its antibiofilm properties (biofilm reduction by approximately 6% compared to the unmodified material, p < 0.05) without cytotoxic effects against human fibroblasts (cell viability near 100%). Thus, modified flow type composite may be considered as a candidate to be used as restorative material since it exhibits both nontoxicity and antibiofilm properties.

Curdlan hydrogel obtained after thermal gelling exhibits elasticity and high water-absorbing capacity. However, its modifications leading to the increase of biofunctionality usually alter its solubility and reduce mechanical parameters. Therefore, curdlan hydrogel was modified by deposition of polydopamine to improve its capacity to bind biologically active molecules with free amino groups. It exhibited the unchanged structure, mechanical properties and increased soaking capacity. Aminoglycoside antibiotic (gentamicin) as a model molecule was effectively immobilized to such modified curdlan via quinone moiety (but not amino groups) of polydopamine. Approximately 50 % of the immobilized drug was released following Fickian diffusion and inhibited the bacterial growth in matrix-surrounding medium in prolonged manner. The remaining drug amount was stably attached and prevented the hydrogel against bacterial adhesion even when all the mobile drug has been released. Therefore, polydopamine-modified curdlan hydrogel shows the potential for fabrication of functional materials for different purposes, including drug-loaded biomaterials., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

This study reports a novel impedimetric immunosensor for protein D detection in purified and bacterial (Haemophilus influenzae, Hi) samples. The detection was based on antigen recognition by anti-protein D antibodies (apD) immobilised at the maze-like boron-doped carbon nanowall electrodes (B:CNW). The B:CNW electrodes were synthesised, and their surface was characterised by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) methods. The sensor was prepared in a two-step procedure: apD were covalently linked on the previously modified B:CNW electrodes using diazonium salt. Modification steps were controlled by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) measurements. The immunosensor exhibited excellent electrochemical performance, stability, satisfactory sensitivities, and linear ranges for antigen detection. Protein D was detected down to 2.39 × 10 2 fg/mL with a linear range extending from 3.37 × 10 -11 to 3.37 × 10 -3 μg/mL (in purified sample). Next, Hi's LOD was 5.20 × 10 2 CFU/mL with a linear range of 8.39 × 10 1 -8.39 × 10 3 CFU/mL. Selectivity studies showed no reaction with negative samples as Streptococcus pyogenes, Streptococcus pneumoniae or Bordetella parapertussis bacteria. Therefore, the new approach is suitable for rapid and quantitative detection of Hi, and is a good candidate for further tests on clinical samples., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The ternary HAp/curdlan/nanomagnetite hybrids with ceramic and polymer phase incorporation of magnetite nanoparticles (MNPs) were fabricated to study their heating ability under action of the alternating magnetic field (AMF), 808 nm near infrared laser radiation (NIR) and their synergic stimulation. The energy conversion was evaluated in terms of the specific absorption rate (SAR) as a function of the MNPs concentration in composites and to estimate their potential in temperature-controlled regenerative processes and hyperthermia. Measurements were carried out on dry and Ringer's solution soaked composite materials in order to mimic in situ conditions. It was found that the MNPs release during prolonged experiment is limited and has no significant effect on energy conversion emphasizing stability of the hybrids. Incorporation of the MNPs in polymer phase of the hybrid can additionally limit particle leaking as well as plays a role as insulating layer for the heat dissipation lowering the risk of sample overheating. In general, it was shown that maximum temperature of hybrid can be achieved in a relatively short time of exposure to stimulating factors whereas its control can be done through optimization of experiment conditions. MNPs incorporation into the curdlan (polymer phase) lead to strengthening of the mechanical properties of the whole network., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: The oral environment can negatively affect the physical properties of fiber-reinforced composite (FRC) materials, which can lead to the deterioration of mechanical stability and reduce the span of their clinical usefulness., Objectives: The aim of this study was to determine the influence of artificial saliva on the selected mechanical properties of FRC., Material and Methods: The core of the polymer material selected for the study was a bundle of ultrahighmolecular-weight polyethylene (UHMWPE) fibers. Fourteen samples were stored in an incubator at 37°C, in 20 mL of artificial saliva solution, and weighed on days 1 and 28. At the same time, mechanical tests were performed, including the measurements of Young's modulus, tensile stress, maximum tensile force, and tensile deformation., Results: The analysis of basic statistics together with the results of the Shapiro-Wilk test and the distribution of Spearman's rho coefficient showed a strong negative relationship between the pair of variables - tensile deformation and the sorption of synthetic saliva. The results related to Young's modulus of elasticity and tensile stress were not statistically significant., Conclusions: Water penetration into the space between the fibers does not adversely affect the mechanical properties of the material tested. In the static tensile test, high and desired mechanical strength was observed, which may justify the effective use of this type of material in clinical practice and may be a good alternative to prosthetic restorations, whose retention is obtained only through a mechanical connection with the abutment tooth.

There are many methods widely applied in the engineering of biomaterials to improve the mechanical properties of the dental composites. The aim of this study was to assess the effect of modification of dental composites with liquid rubber on their mechanical properties, degree of conversion, viscosity, and cytotoxicity. Both flow and packable composite consisted of a mixture of Bis-GMA, TEGDMA, UDMA, and EBADMA resins reinforced with 60 and 78 wt.% ceramic filler, respectively. It was demonstrated that liquid rubber addition significantly increased the fracture toughness by 9% for flow type and 8% for condensable composite. The influence of liquid rubber on flexural strength was not statistically significant. The addition of the toughening agent significantly reduced Young's modulus by 7% and 9%, respectively, while increasing deformation at breakage. Scanning electron microscopy (SEM) observations allowed to determine the mechanisms of toughening the composites reinforced with ceramic particles. These mechanisms included bridging the crack edges, blocking the crack tip by particles and dissipation of fracture energy by deflection of the cracks on larger particles. The degree of conversion increased after modification, mainly due to a decrease in the matrix resin viscosity. It was also shown that all dental materials were nontoxic according to ISO 10993-5, indicating that modified materials have great potential for commercialization and clinical applications.

The purpose of this study was to determine whether dialysis method allows for efficient protein entrapment in curdlan-based hydrogel. Thus, bovine serum albumin, a model of bioactive protein, was incorporated into curdlan matrix using ion-exchanging dialysis method against two concentrations of CaCl 2 solution - 2% and 10%, respectively. Then, physicochemical, mechanical, and biological properties of the bovine serum albumin-loaded curdlan hydrogels were evaluated. Received results show that neither the polymer nor the entrapment procedure change the bovine serum albumin conformation (as proven by Fourier transform infrared spectroscopy and circular dichroism spectroscopy) and the process guarantees high protein entrapment efficiency (above 95%). The curdlan-based carrier obtained against 2% of CaCl 2 solution was found to possess higher swelling ability, release greater amounts of bovine serum albumin (up to 4 weeks), and exhibit superior biocompatibility compared to curdlan-based carrier obtained against 10% of CaCl 2 solution. Thus, dialysis method enables efficient protein entrapment in curdlan hydrogel and obtained protein carrier via dialysis method into 2% of CaCl 2 solution may be considered as a promising protein delivery system especially for tissue engineering applications. It should be noted that we are the first who presented effective method for protein entrapment in curdlan hydrogel., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Aim: The studies on tooth structure provided basis for nanotechnology-based dental treatment approaches known as nanodentistry which aims at detection and treatment of oral pathologies, such as dental caries and periodontal diseases, insufficiently being treated by conventional materials or drugs. This review aims at defining the role of nanodentistry in the medical area, its potential and hazards., Materials & Methods: To validate these issues, current literature on nanomaterials for dental applications was critically reviewed., Results: Nanomaterials for teeth restoration, bone regeneration and oral implantology exhibit better mechanical properties and provide more efficient esthetic outcome. However, still little is known about influence of long-term function of such biomaterials in the living organism., Conclusion: As application of nanomaterials in industry and medical-related sciences is still expanding, more information is needed on how such nano-dental materials may interfere with oral cavity, GI tract and general health.