Damian Kusz

Interactions Between Concentrations of Chemical Elements in Human Femoral Heads

Environmental and occupational exposure to various metals has been a major public health concern and the subject of many studies. With the development of industry and transportation, environmental pollution has markedly worsened. As a result, metals are now ubiquitous and are absorbed into the body with food, drinking water, and polluted air. Exposure to these elements leads to numerous health problems, affecting almost every system of the human body, including the skeletal system. Bone is a specific research material that is difficult to obtain, therefore chemical analyses of metal concentrations in this tissue are rarely found in the literature. Nevertheless, bone, due to its long regeneration period, can serve as a biomarker of a long-term metal accumulation resulting from environmental or occupational exposure. Our study was conducted on bone samples harvested from inhabitants of the Upper Silesia region during hip replacement surgery. Femoral heads removed during surgery were sectioned into slices and further subdivided into samples comprising articular cartilage, cortical bone, and trabecular bone. Concentrations of 12 trace elements were measured with an atomic absorption spectrophotometry method. We found significant correlation between concentrations of these metal elements in the samples of cortical bone. This is determined not only by the physiological functions of these metals in hydroxyapatite, but also by the specific mineral structure of the bone tissue.

Novel bioactive polyester scaffolds prepared from unsaturated resins based on isosorbide and succinic acid.

In this study new biodegradable materials obtained by crosslinking poly(3-allyloxy-1,2-propylene succinate) (PSAGE) with oligo(isosorbide maleate) (OMIS) and small amount of methyl methacrylate were investigated. The porous scaffolds were obtained in the presence of a foaming system consisted of calcium carbonate/carboxylic acid mixture, creating in situ porous structure during crosslinking of liquid formulations. The maximum crosslinking temperature and setting time, the cured porous materials morphology as well as the effect of their porosity on mechanical properties and hydrolytic degradation process were evaluated. It was found that the kind of carboxylic acid used in the foaming system influenced compressive strength and compressive modulus of porous scaffolds. The MTS cytotoxicity assay was carried out for OMIS using hFOB1.19 cell line. OMIS resin was found to be non-toxic in wide range of concentrations. On the ground of scanning electron microscopy (SEM) observations and energy X-ray dispersive analysis (EDX) it was found that hydroxyapatite (HA) formation at the scaffolds surfaces within short period of soaking in phosphate buffer solution occurs. After 3h immersion a compact layer of HA was observed at the surface of the samples. The obtained results suggest potential applicability of resulted new porous crosslinked polymeric materials as temporary bone void fillers.

The role of decorin and biglycan dermatan sulfate chain(s) in fibrosis-affected fascia

Organ fibrosis is associated with excessive deposition of dermatan sulfate (DS) in the extracellular matrix (ECM) of the affected tissue. However, the significance of DS in fibrosis process is poorly known. Thus, we have analyzed both in vitro and in vivo the binding potential toward fibroblast growth factor-2, platelet-derived growth factor BB and fibronectin (FN) of DS representing glycosaminoglycan (GAG) chains of two proteoglycans decorin and biglycan derived from fascia undergoing fibrosis due to Dupuytrens disease. Moreover, to investigate the relation between DS structure and its binding properties to above ligands, we have also studied the interactions of the GAG chains from normal porcine skin decorin and biglycan. The examined interactions, especially those engaging extractable pool of both human and porcine decorin DS, are characterized by very high affinity and low capacity. Moreover, the presence of iduronate residues is not essential for the DS binding to all studied ligands and the interactions more strongly depend on the GAG sulfation pattern. All investigated interactions have biological relevance as judged from the coexistence of decorin (and biglycan) DS, both growth factors and FN in supra-molecular complexes localized in ECM of both fibrous and normal human fascia. Moreover, these complexes also include collagen type III. It seems that fascia fibrosis process when compared with physiological circumstances is associated with the preservation of at least some functions of decorin and biglycan DSs such as the regulation of growth factor bioavailability and most probably influence FN fibrillogenesis as well as coupling of various fibrilar matrix element assembly.

Optimization of Genetic Engineering and Homologous Recombination of Collagen Type I Genes in Rat Bone Marrow Mesenchymal Stem Cells (MSC)

Mutations in COL1A1 or COL1A2 genes lead to osteogenesis Imperfecta (OI) in humans. There are three possiblities to successfully treat OI including (1) gene therapy, (2) mesenchymal stem cell (MSC) therapy, or (3) a combination of both. The aim of this study was to develop a model for combined gene/cell OI therapy by targeting Col1a1 and Col1a2 genes with isogenic sequences from corresponding human genes in rat bone marrow (BM)-derived MSCs. The recombination efficacy was tested for five different rat-human-rat hybrid DNAs with rat fragments that were 1 to 4 kb long. For selection of transfected clones a neomycine resistance gene was cotransfected, and clones resistant to G418 (G418(+)) were recovered and screened for integration of specific gene loci in the rat genome. Over 90% of G418(+) clones correctly integrated the rat-human-rat hybrid DNAs, and both OI loci in the rat genome were targeted to a similar degree. Longer homologous sequences integrated into rat collagen genes approximately 10 times more efficiently. Based on our data the nonviral gene targeting technology could be potentially employed to repair collagen genes in OI patients.

Novel crosslinkable polyester resin–based composites as injectable bioactive scaffolds

ABSTRACT In this study new composite materials obtained by crosslinking two polyester resins were investigated. The solid composite material and the scaffolds with varied porosity were obtained in the presence of a foaming system consisted of calcium carbonate/citric acid mixture. It was found that the presence of citric acid solution influenced rheological behavior of liquid formulations as well as morphology and mechanical properties of cured materials. SEM observations and analysis by energy-dispersive X-ray dispersive spectroscopy confirmed the presence of hydroxyapatite formed at the scaffolds surfaces in phosphate buffer solution. The MTS cytotoxicity assay was carried out for extracts from selected composite materials using the human osteosarcoma cells (SaOS-2). GRAPHICAL ABSTRACT

Gait analysis in patients after unilateral hip arthroplasty.

BACKGROUND Osteoarthritis (OA) is the most common joint pathology and the main cause of disability in elderly persons. Arthroplasty still remains the most effective treatment of OA. Routine post-operative patient assessment does not include an objective functional examination leading to conclusions regarding the need of further rehabilitation. This role is played by gait analysis performed in patients after arthroplasty. The aim of the study was to conduct a quantitative and qualitative analysis of selected gait parameters in patients after unilateral cementless hip arthroplasty. MATERIAL AND METHODS The study involved a group of 16 patients who were examined before and after hip arthroplasty. Gait analysis was conducted before surgery and at least 6 months after the procedure. The Smart DX BTS system for spatial gait analysis was used. RESULTS The duration of the stance phase on the affected side was 63.8 [% gait cycle] and was significantly shorter (p<0.05) than the phase on the unaffected side, with a duration of 69.4 [% gait cycle]. After surgery, the duration of swing phase on the unaffected side increased (p<0.05) from 30.6 to 35.1 [% gait cycle]. A statistically significant change was also found in the double support phase (the arthrotic limb as the front limb), which was markedly shortened. The average length of a single and double step, cadence, average gait velocity, and the velocity of leg swing in the swing phase increased. The range of hip mobility increased in all planes, especially in the sagittal plane. CONCLUSION The space and time gait parameters with regard to the operated leg after hip arthroplasty indicate an improvement as compared with the baseline results; however, they do not reach the values found in healthy persons.

Complex influence of dermatan sulphate on breast cancer cells

Tumor transformation and progression both lead to extracellular matrix remodeling, which is also reflected in an alteration in the proportion of dermatan sulphate (DS) and chondroitin sulphate (CS) and an accumulation of the latter. In addition, a significant increase in the 6-O-sulphated disaccharide contribution to the structure of both glycosaminoglycans has been observed. It is commonly accepted that CS is more permissive for tumor growth than DS. However, the detailed role of DS in tumor progression is poorly known. We tested the effects of structurally different DSs on the behavior of cultured breast cancer cells. At a high dose (10 µg/mL), all of the DSs significantly reduced cancer cell growth, although some differences in the efficiency of action were apparent. In contrast, when used at a concentration of 1 µg/mL, the examined DSs evoked different responses ranging from the stimulation to the inhibition of cancer cell proliferation. The highest stimulatory activity was associated with fibrosis-affected fascia decorin DS, which is characterized by a particularly high content of 6-O-sulphated disaccharides. Further reduction in DS concentration to 0.5 µg/mL preserved majority of biological effects which were apparent at a dose of 1 µg/mL. The enzymatic fragmentation of the DSs, particularly by chondroitinase AC I, abolished the impact exerted by 1 µg/mL of the intact DS chains and sometimes resulted in the opposite effect. In contrast to DSs, highly sulphated C-6-S exhibited no effect on the cancer cells. Our data revealed the complexity of the effects of DSs on breast cancer cells, which include both co-receptor activity and the prevention of vascular endothelial growth factor action. In addition, the biological effect of DSs is strongly dependent not only on the glycosaminoglycan structure but also on its content in the cancer environment.

Notch signaling pathway and gene expression profiles during early in vitro differentiation of liver-derived mesenchymal stromal cells to osteoblasts

Notch signaling is a key signaling pathway for cell proliferation and differentiation. Therefore, we formulated a working hypothesis that Notch signaling can be used to detect early osteoblastic differentiation of mesenchymal stromal cells. Changes in expression and distribution of Notch 1, 2, 3, and Delta1 in the cytoplasm and nuclei of rat liver-derived mesenchymal stromal cells differentiating into osteoblasts were investigated, together with the displacement of intracellular domains (ICDs) of the receptors. In addition, an oligonucleotide microarray was used to determine the expression of genes known to be linked to selected signaling pathways. Statistically significant changes in the number of cells expressing Notch1, Notch2, and Delta1, but not Notch3, and their activated forms were detected within 24 h of culture under osteogenic conditions. Although the number of cells expressing Notch3 remained unchanged, the number of cells with the activated receptor was significantly elevated. The number of cells positive for Notch3 was higher than that for the other Notch receptors even after 48 h of differentiation; however, a smaller fraction of cells contained activated Notch3. Culture mineralization was detected on day 4 of differentiation, and all analyzed receptors were present in the cells at that time, but only Delta1 was activated in twice as many cells than that before differentiation. Thus, the three analyzed receptors and ligand can serve as markers of very early stages of osteogenesis in stromal cells. These early changes in activation of the Notch signaling pathway were correlated with the transcription of several genes linked to osteogenesis, such as Bmps, Mmps, and Egfr, and with the regulation of cell cycle and apoptosis.

Osteitis in the Course of Pyodema Gangrenosum. Case Raport

We present the case of a male patient admitted to the Department of Orthopaedics and Musculoskeletal Traumatology, Medical University of Silesia (MUS) in Katowice, due to a right hindfoot abscess with calcaneal infiltration and pain in the forehead and the back, with evidence of local inflammation. The patient had a history of ulcerative colitis and sclerosing cholangitis was suspected. During the hospital stay, the patient underwent calcaneal CT, surgery (resection of an inflammatory focus) and MRI of the thoracic and lumbosacral spine, which revealed inflamed spinous processes of the Th10, Th11 and Th12 vertebrae. Numerous cultures and histo-pathological examinations were performed. Specialist consultations were obtained. The differential diagnosis included myeloproliferative and lymphoproliferative processes as well as skin and soft tissue neoplasms. The clinical presentation and examination results led to a diagnosis of pyoderma gangrenosum and the patient was referred to the Department of Internal Medicine and Rheumatology of the MUS to undergo further treatment.

Variation in the Posterior Condylar Angle

BACKGROUND Clinical success of TKR depends to a large extent on the correct positioning of the implants. The femur cut is usually made in 3° of external rotation relative to the posterior aspect of the femoral condyles, which is a typical value of the Posterior Condylar Angle (PCA). The aim of this study was to assess variation in the PCA and to identify possible correlations between the value of the PCA and the following parameters: gender, body side, body height and weight (BMI). MATERIAL AND METHODS The study group comprised 75 patients who underwent an Angio-CT study between 2012 and 2014 due to a suspected vascular disorder. For each knee, we measured the Posterior Condylar Angle and the Posterior Twist Angle. RESULTS The mean Posterior Condylar Angle was 2.7±2.1°. The differences between males and females were not statistically significant. The angles showed a high degree of symmetry between the contralateral knees. CONCLUSIONS 1. Positioning of the femoral component of the knee joint endoprosthesis parallel to the transepicondylar line requires resecting the femur at approximately 3° of external rotation relative to the line tangential to the posterior aspect of the femoral condyles. This angle, however, may vary from 3.6° of internal rotation to 9.0° of external rotation which should be taken into consideration by the operating surgeon. 2. The values of the Posterior Condylar Angle do not correlate with gender, age, Body Mass Index and body side (with notable, near-perfect symmetry between the contralateral limbs). 3. In female patients, height and body weight may influence the Posterior Condylar Angle, but these correlations would require further studies of larger groups of patients. In male patients, we were unable to find such correlations.