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Hydrogels from natural polymers such as sodium alginate have great potential in regenerative medicine because of their biocompatibility, biodegradability, mechanical properties, bioresorption ability, and relatively low cost. Sodium alginate, a polysaccharide derived from brown seaweed, is the most widely investigated and used biomaterial in biomedical applications. Alginate dressings are also useful as a delivery platform in order to provide a controlled release of therapeutic substances (e.g., pain-relieving, antibacterial, and anti-inflammatory agents). In our work, we aimed to analyze process of degradation of alginate hydrogels. We also describe an original hybrid crosslinking process by using not one, as usual, but a mixture of two crosslinking agents (calcium chloride and barium chloride). We proved that different crosslinking agents allow producing hydrogels with a spectrum of mechanical properties, similar to the urethra tissue. Hydrogels were formed using a dip-coating technique, and then examined by mechanical testing, FTIR (Fourier-Transform Infrared Spectroscopy), and resorption on artificial urine. Obtained hydrogels have a different degradation rate in artificial urine, and they can be used as a material for healing of urethra injuries, especially urethra strictures, which significantly affect the quality of life of patients.

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The aim of this work was to assess the numerous approaches to structural and material modeling of brain tissue under dynamic loading conditions. The current technological improvements in material modeling have led to various approaches described in the literature. However, the methods used for the determination of the brain’s characteristics have not always been stated or clearly defined and material data are even more scattered. Thus, the research described in this paper explicitly underlines directions for the development of numerical brain models. An important element of this research is the development of a numerical model of the brain based on medical imaging methods. This approach allowed the authors to assess the changes in the mechanical and geometrical parameters of brain tissue caused by the impact of mechanical loads. The developed model was verified through comparison with experimental studies on post-mortem human subjects described in the literature, as well as through numerical tests. Based on the current research, the authors identified important aspects of the modeling of brain tissue that influence the assessment of the actual biomechanical response of the brain for dynamic analyses.

Introduction: The aim of this research was to provide a detailed description of the morphology, topography, and histometry of rabbit accessory genital glands. Material and Methods: Seven male New Zealand White rabbits, 3–4 months of age and weighing 2.1–3 kg were used for the study. The whole urethra from the urinary bladder to the external urethral orifice accompanied by accessory genital glands was sliced at intervals of 1 mm. The serial sections were prepared with haematoxylin-eosin (H&E) and Movat–Russell modified pentachrome stain. Results: A detailed description of the morphology and morphometry was provided. The topography of the organs was explained on the basis of characteristic cross-sections on histological slides. The inconsistent nomenclature and descriptions of these glands by different authors were also discussed. Conclusion: The morphometric analysis indicated that some of the glands described have similar dimensions in different individuals, while others like paraprostates revealed high diversity in the number of lobes, their size, and their structure. The accessory glands are also good topographic markers which precisely define the segment of the urethra. The terms “proprostate”, “prostate”, and “paraprostates” as the nomenclature of the prostate complex reflect the location of these glands well and indicate their common origin and function.

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Purpose. To compare stability and subsidence associated with 3 types of cervical spine stabilisation. Methods. The C3 to C4 vertebrae of 28 Polish pigs were used. Pigs with intact vertebrae (group 1) underwent standard anterior cervical discectomy (group 2), followed by stabilisation using a cage alone (group 3), a cage with plate (group 4), or a plate-cage (group 5). Cervical spine stability and subsidence were compared in all 5 groups. Results. Stability was significantly increased after stabilisation by a cage with plate or a plate-cage, but not by a cage alone. The difference between stabilisation by a cage with plate and a plate-cage was not significant. Subsidence was maximal after the Comparative biomechanical study of cervical spine stabilisation by cage alone, cage with plate, or plate-cage: a porcine model