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The “Multifunctional biologically active composites for applications in bone regenerative medicine” project is carried out within the TEAM-NET program of the Foundation for Polish Science financed by the European Union under the European Regional Development Fund. The authors gratefully acknowledge the financial support. T.E.L.D. thanks N8 Agrifood for its financial support in the framework of the pump priming grant “Food2Bone”. Hydroxyapatite (HAp) is a bioactive ceramic with great potential for the regeneration of the skeletal system. However, its mechanical properties, especially its brittleness, limit its application. Therefore, in order to increase its ability to transmit stresses, it can be combined with a polymer phase, which increases its strength without eliminating the important aspect of bioactivity. The presented work focuses on obtaining organic–inorganic hydrogel materials based on whey protein isolate (WPI) reinforced with nano-HAp powder. The proportion of the ceramic phase was in the range of 0–15%. Firstly, a physicochemical analysis of the materials was performed using XRD, FT-IR and SEM. The hydrogel composites were subjected to swelling capacity measurements, potentiometric and conductivity analysis, and in vitro tests in four liquids: distilled water, Ringer’s fluid, artificial saliva, and simulated body fluid (SBF). The incubation results demonstrated the successful formation of new layers of apatite as a result of the interaction with the fluids. Additionally, the influence of the materials on the metabolic activity according to ISO 10993-5:2009 was evaluated by identifying direct contact cytotoxicity towards L-929 mouse fibroblasts, which served as a reference. Moreover, the stimulation of monocytes by hydrogels via the induction of nuclear factor (NF)-κB was investigated. The WPI/HAp composite hydrogels presented in this study therefore show great potential for use as novel bone substitutes.

This work describes measurement methodology on acrylic acid-based hydrogels with nanogold and starch, including evaluation of pro-inflammatory activity and cytotoxicity by MTT reduction assay, swelling capacity, tensile strength using Brookfield texture analyzer, surface morphology by scanning electron microscopy, structure by FT-IR spectroscopy, crystallinity by X-ray diffraction and hydrogel behaviour in simulated body fluids. The modified polymers exhibited approx. 75% lower deformation than unmodified polymer. Hydrogels showed buffering properties in simulated body fluids. Hydrogels containing 5–10% starch solution did not exhibit cytotoxicity. Cells exposed to unmodified hydrogel and to hydrogels containing 5% and 10% starch solutions were characterized by the desired morphology. Importantly, hydrogel nanocomposites have not showed pro-inflammatory activity. It was proved that highly developed specific surface area of modified hydrogels affected their sorption properties. Nanogold present in nanocomposites did not affect directly their physicochemical properties but, due to its features, antibacterial activity of so modified materials could be enhanced.

Medical grade UHMWPE-s: GUR 1020 and 1050, were subjected to ion bombardment with H 2 + , He+, Ar+ or Ag+ of different energy and various doses. The work presents changes to micromechanical profiles and surface morphology (AFM, SEM) of polyethylenes due to the treatment. Mechanisms behind the modification have been proposed owing to structural and chemical analyses by s-SIMS, FTIR-IRS, confocal Raman microscopy and “nuclear depth profiling”. Studies revealed that hardness of the surface layer increases due to radiolysis, probably leading to cross-polymerization of polyethylene. The depth of modification is limited to the penetration of ion beam, being dependent on a dose and a kind of ions applied. The treatment results additionally in oxidation, which together with a development of the surface geometry is responsible for its hydrofilization and, in some cases bacteriostatic character. Friction and wear of polyethylenes under a high load, adequate to extreme conditions of exploitation of hip joints, can be reduced even by three times, due to a proper ion beam treatment.

In the first of two experiments four rumen-cannulated sheep were used to determine the degree of rumen protein degradation in blood meal (BM), fish meal (FM), soybean meal (SBM) or casein (C) using the in sacco method. In the second experiment, four cannulated rams were fed isonitrogenous and isoenergetic diets to ascertain the influence of the same protein feeds on metabolic changes in the rumen and flow of amino acids through the duodenum. Rumen non-degradable N in BM, FM, SBM or C total-N was 74%, 62%, 38% and 11%, respectively. Rumen ammonia-N (NH3-N) was highest (P < 0.05) in lambs fed C, lowest with FM. Source of dietary protein did not affect dry matter or organic matter digestibility in the rumen. Total-N, nonammonia N and amino acid flow through the duodenum was highest (P < 0.05) in lambs fed FM and lowest with C. Combinations of protein sources may best supply amino acids to ruminants in optimal proportions.

Thirty-two rams of Polish Merino breed, average initial body weight 25 kg (SE ± 0.8 kg) were fed isonitrogenous and isoenergetic diets in which the main sources of protein were blood meal (BM), fish meal (FM), soybean meal (SBM) or casein (C). The highest gains (P < 0.05) were obtained in lambs fed FM diets (197 g day−1), followed by BM, SBM and C (181 g, 175 g and 114 g day−1, respectively). Lambs supplemented with C were characterised by the highest protein and energy consumption per kilogram body weight (BW) gain. Source of protein did not affect chemical composition of empty BW. The highest values of the kf coefficient were found in lambs fed FM (0.38) and the lowest in those fed C (0.20). Protein deposition was highest (P < 0.05) in animals fed FM (35.5 g day−1), followed by BM, SBM and C (31.7 g, 30.0 g and 23.7 g day−1, respectively). FM was the optimal source of supplemental protein.

Two experiments were carried out. In the first experiment, four sheep (45 kg) with a cannula in the rumen were used to determine the extent of rumen protein degradation of dehydrated alfalfa (DA), applying the nylon bag technique. In the second experiment, five lambs (25 kg) with cannulas in the rumen and duodenum were fed all-concentrate, pelleted isonitrogenous (about 16% crude protein kg−1 dry matter) and isoenergetic (about 12.8 MJ metabolizable energy kg−1 dry matter) diets containing 0, 5, 10, 15 and 20% of DA in a 5 × 5 Latin square arrangement of treatments. After 24 h incubation period in the rumen, 61.2% DA protein was not degraded in this forestomach. The pH of rumen fluid increased only slightly with the increase of the DA concentration in the diets, while the level of NH3N in the rumen fluid decreased from 9.42 to 4.44 mM l−1 fluid. Total ruminal volatile fatty acid concentration dropped together with the increase of the DA content in diets (from 72.1 to 65.2 mM l−1), whereas acetate to propionate ratio increased significantly (P < 0.05) from 1.61 to 2.08. The highest and statistically significant (P < 0.05) flow of total N (23.17 g day−1), non-ammonia N (22.37 g day−1) and essential (53.74 g day−1), non-essential (77.07 g day−1) and total amino acids (130.81 g day−1) was observed in lambs fed 10% DA.