Histological and morphometrical evaluation of the urethral wall after bioresorbable stent implantation in male New Zealand White Rabbits: A preliminary study.

The aim of the study was the histological and morphometrical evaluation of the urethral wall at three time points after bioresorbable stent implantation in male New Zealand White Rabbits. The research was performed on 26 male New Zealand White rabbits aged 3-4 months and weighing 2.1-3.

Biodegradable Polymers in Biomedical Applications: A Review-Developments, Perspectives and Future Challenges.

Biodegradable polymers are materials that, thanks to their remarkable properties, are widely understood to be suitable for use in scientific fields such as tissue engineering and materials engineering. Due to the alarming increase in the number of diagnosed diseases and conditions, polymers are of great interest in biomedical applications especially. The use of biodegradable polymers in biomedicine is constantly expanding.

Changes in the Mechanical Properties of Alginate-Gelatin Hydrogels with the Addition of with Potential Application in Urology.

New hydrogel materials developed to improve soft tissue healing are an alternative for medical applications, such as tissue regeneration or enhancing the biotolerance effect in the tissue-implant-body fluid system. The biggest advantages of hydrogel materials are the presence of a large amount of water and a polymeric structure that corresponds to the extracellular matrix, which allows to create healing conditions similar to physiological ones. The present work deals with the change in mechanical properties of sodium alginate mixed with gelatin containing .

Numerical Analyses of Fracture Mechanism of the Pelvic Ring during Side-Impact Load.

The aim of this study is the analysis of the multiple pelvis fracture mechanism in side-impact dynamic load cases. The elaborated numerical model of a pelvis complex includes pelvic and sacral bones as well as soft tissues such as ligaments and cartilages. The bone has been modelled as a viscoelasticity material based on the Johnson-Cook model.

Evaluation of Selected Properties of Sodium Alginate-Based Hydrogel Material-Mechanical Strength, μDIC Analysis and Degradation.

The search for ideal solutions for the treatment of urethral stenosis continues. This includes developing the material, design, while maintaining its optimal and desired properties. This paper presents the results of the research conducted on sodium alginate-based hydrogel material (AHM), which may be used as a material for stents dedicated to the treatment of pathologies occurring in the genitourinary system.

Determination of Stent Load Conditions in New Zealand White Rabbit Urethra.

Background: Frequency of urethral stenosis makes it necessary to develop new innovative methods of treating this disease. This pathology most often occurs in men and manifests itself in painful urination, reduced urine flow, or total urinary retention. This is a condition that requires immediate medical intervention.

Histological and morphometric evaluation of the urethra and penis in male New Zealand White rabbits.

This stereudy aimed at performing a histological and morphometric evaluation of the urethra and penis of male rabbits. Seven male New Zealand White rabbits weighing 2.1-3 kg were used in the study.

Accessory Genital Glands in the New Zealand White Rabbit: A Morphometrical and Histological Study.

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.

Material and Structural Modeling Aspects of Brain Tissue Deformation under Dynamic Loads.

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.

Influence of energy absorbers on Malgaigne fracture mechanism in lumbar-pelvic system under vertical impact load.

Malgaigne fractures are the most common and widespread pelvic injuries resulting from the shear forces the action mechanism of which has not been explained in the literature yet. Military accidents with improvised explosive devices (IED) perfectly reflect this type of pelvic fracture. The finite element (FE) model of lumbar-pelvic complex (LPC) was developed based on computed tomography (CT) scans with the seat including steel frame, padding and soft tissue.

The influence of osteoporotic bone structures of the pelvic-hip complex on stress distribution under impact load.

Purpose: The aim of this study was to determine the effect of bone mineral density (BMD) on the stress distribution in pelvic-hip complex (PHC) model which included bone structures and soft tissues. Bone mass changes in osteoporosis and osteopenia were considered in this analysis. In addition, the relations between force direction and stress distribution causing PHC fractures were determined.

The mechanical properties of human dentin for 3-D finite element modeling: Numerical and analytical evaluation.

Background: The FEM is often used in investigations of dentin loading conditions; however, its anisotropy is mostly neglected.

Objectives: The purpose of the study was to evaluate the anisotropy and the elastic properties of an equivalent homogenous material model of human dentin as well as to compare isotropic and anisotropic dentin FE-models.

Material And Methods: Analytical and numerical dentin homogenization according to Luciano and Barbero was performed and E-modulus (E), Poisson's ratios (v) G-modulus (G) were calculated.

An analysis of the effect of impact loading on the destruction of vascular structures in the brain.

Subdural hematomas are one of the frequent complications of head injuries. Such hematomas result from exceeding the border strength values of bridging veins. Subdural haemorrhages are life-threatening and are a frequent cause of considerable pathologies.

Comparative studies of cervical spine anterior stabilization systems--Finite element analysis.

Background: The object of the study was to assess the impact of one-level stabilization of the cervical spine for both anterior static and dynamic plates. Segments C2-C6 of the cervical spine, were investigated, from which was determined the stress and strain fields in the region of implantation and adjacent motion segments. The purpose was the comparison of changes that affect the individual stabilizers.

Biomechanical characteristics of the jump down of healthy subjects and patients with knee injuries.

Purpose: The aim of this study is to investigate the drop jump performance of male patients who underwent ACLR and a control group using combined data acquisition system.

Methods: A total of 28 male subjects aged 20 to 26 were studied: 22 did not show and were not diagnosed with any knee joint dysfunction (the control group) and six men who underwent ACLR of the left limb (group of patients). The control group was age, height and body mass matched.

Experimental and constitutive modeling approaches for a study of biomechanical properties of human coronary arteries.

The study concerns the determination of mechanical properties of human coronary arterial walls with both experimental and constitutive modeling approaches. The research material was harvested from 18 patients (range 50-84 years). On the basis of hospital records and visual observation, each tissue sample was classified according to the stage (0, I, II, III) of atherosclerosis development (SAD).

Biomechanical characteristics of the porcine denticulate ligament in different vertebral levels of the cervical spine-preliminary results of an experimental study.

Background: Few studies exist on the mechanical properties of denticulate ligaments and none report the variation in these properties at different levels of the spine. The aim of this study was to perform an experimental determination of load-extension and stress-strain characteristics of the denticulate ligament and to establish if their properties change at different vertebral levels of the cervical spine.

Method: The study was carried out on a total of 98 porcine denticulate ligament samples dissected from seven fresh porcine cervical spinal cord specimens.

Finite element modelling of the cervical spinal cord injury -- clinical assessment.

The aim of the study was to evaluate the efficiency of Finite Element Method (FEM) modelling of the clinical cases of traumatic cervical spinal cord injury (SCI). The study population consisted of 28 patients suffering from traumatic cervical spine injury with (study group) and without (control) neurological deficits. A numerical simulation of the trauma event was performed, based on validated 3D FEM model.

FT-Raman spectroscopic study of human skin subjected to uniaxial stress.

Fourier Transform Raman Spectroscopy was used to investigate the molecular changes of structural proteins in human skin subjected to strain. In the Raman spectrum of unstrained skin, bands assigned mainly to collagen and elastin were observed at 1658 cm(-1) (amide I), 1271 and 1255 cm(-1) (amide III), and 935 and 817 cm(-1) (C-C stretching modes of the protein backbone). Moreover, bands characteristic for amino acids were observed at 1336 cm(-1) (desmosine), 1004 cm(-1) (phenylalanine), 919 and 856 cm(-1) (proline), and 877 cm(-1) (hydroxyproline).

Mechanical properties of cervical dura mater.

The aim of the study was to determine experimentally the stress as strain function as well as the orthotropy and heterogeneity of porcine dura mater of the cervical spinal cord. Material was divided into groups based on the place of collection, considering the dorsal side and ventral side, specifying the number of cervical vertebra, and the direction of tension of the sample - longitudinal or circumferential. Experimental studies were conducted with the MTS Synergie 100 testing machine.

Numerical model of the human cervical spinal cord--the development and validation.

The influence of mechanical load on the extent of nervous tissue damage in the spinal cord at the time of trauma is presently incontestable. Although numerical modelling cannot fully replace physical testing, it seems to be the perfect complement to experiments in terms of the analysis of such a complex phenomenon as traumatic spinal cord injury. Previous numerical models of the human cervical spinal cord have been limited by several factors: two-dimensional modelling, spinal cord geometry simplification and incomplete reflection of specific anatomical and biomechanical relations of the objects being modelled.

Noninvasive ultrasonic measuring system for bone geometry examination.

Background: Bone deformities are typically identified through standard radiograms. Since X-ray examinations are easily applied and offer high quality imaging, noninvasive techniques are not commonly used in bone diagnostics. Nevertheless, nonradiological techniques are considered necessary because of the harmful effects of X-ray radiation.

Biomechanical effect of rapid mucoperiosteal palatal tissue expansion with the use of osmotic expanders.

The comparative study was performed to investigate the biomechanical properties (maximum tangential stiffness, maximum tangential modulus and tensile strength) of expanded mucoperiosteal palatal tissue after rapid expansion regimen correlated with histological findings. Rabbit palatal model was used to correlate the non-operated control group, sham-operated control (subperiosteal tissue dissection) groups and 24- and 48-hour tissue expansion groups. There was no observed damage of tissue collagen network in both tissue expansion groups analyzed immediately after expansion, and biomechanical profile was not significantly different from the profile of control groups.

The effect of substrate roughness on the surface structure of TiO(2), SiO(2), and doped thin films prepared by the sol-gel method.

Pure and calcium-doped silica and titanium dioxide thin films were prepared by the sol-gel method. Two different metallic substrates, i.e.