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Standard procedures regarding osteoblast cells deposition on different subtrates to test the biocompatibility of materials are not available. Aspects related to cells morphology depending on their number on the surface area of the substrate were studied for the first time. Osteoblasts were successfully isolated from residual bone resulted from two different patients after total hip arthroplasty. Different numbers of osteoblasts in populations (3x104 cells/cm2, 6x104 cells/cm2, 1x105 cells/cm2) were deposited on tissue culture polystyrene for 7 and 10 days of incubation. Results suggested that the protocol of osteoblasts deposition should be adjusted to assure a fair distribution of cells on the entire available area of the substrate, possible if a very good dispersion in the medium is achieved prior to deposition. Some other key factors in cells appropriate development, such as substrate nature, topography and incubation time,were detected. The present investigation helps declaring specific standards with respect to the biocompatibility testing of materials using osteoblast populations. Further investigations may lead to the creation of databases and the establishment of standards regarding bicompatibility researches that involve osteoblasts populations.

Dental resin composites have a wide applicability in the dental field. They exhibit their own chemical composition that imparts certain physico-mechanical properties. The machining of the pieces of these composites must be sufficiently light, without affecting their strength. For processing these parts, respectively of the dental work, is used or carbide burs, or diamond burs, depending on the mechanical strength of the composite. To determine composite behaviour under action of the conical finishers was simulated their behaviour in specific simulation programs. As a result, stress concentrators may appear from the first processing which may affect the later resistance of the piece or dental work.

During conûict situations, the combat staff is exposed to a wide variety of aggressions, such as temperature and pressure variations and dynamic impacts (from ammunition or fragments). Textiles used in the manufacture of the military uniforms and devices have always played an important role in defending the military against these hazards, and an adequate level of individual protection equipment is required. In this respect, novel fibre-reinforced polymer composite materials for military application, such as reducing blunt trauma for ballistic protection equipment, have been studied in terms of thermal and mechanical properties and ballistic protection, obtaining very good results.

By electrical determinations, digital microscopy and visual observations, the anticorrosive insulation capacity of the paint layers applied to the three sections of a bridge over the Tisza River was assessed. The visual observations have highlighted the fact that on the Eastern section repainted in 2013, biofouling increases are significant (covers up to 10 % of the surface) - both ferns have been identified (Hypogymnia physodes and Xanthoria parietina), filamentous molds (Aspergillus fumigatus and Aspergillus niger) as well as algae and moss (green - capable of photosynthesis). On paint applied in 1986, no bio fouling was visible but the painting material is aged and shows rust traces (5-10 % of the surface) and exfoliation between the paint layers (10-20 % of the surface). No bio fouling and/ or exfoliation/ degradation of the paint layer have been observed on the paint applied in 2014. Determinations of electrical insulation resistance correlated with those of the paint layers’ thickness are closely related to the visual observations. The values obtained for the specific resistivity of the paint layers applied in 2013 (with bio fouling increases) are approx. 38 times lower than those applied in 2014. These findings suggest that the painting material used in 1983 for the top coat realization, showed major qualitative vices.

The influences of hypochlorite DM with oil ingredient and without it, which is introduced into the armament not only by the Czech Armed Forces Chemical Corps, but also by the chemical services specialists of the Czech Republic Fire Rescue Service, on a substrate consisting of a barrier material based on isobutylene-isoprene rubber (butyl rubber) were presented in this paper. Based on the repeated exposure of the substrate formed by the barrier layer material selected by this decontamination mixture and its subsequent rinsing, a change of the breakthrough time has been studied using the MIKROTEST method employing the chemical warfare agent of sulfur mustard and Congo red as a detecting agent.

The survival of CKD patients has known significant improvement with the appearance of extrarenal clearance methods. Being a domain in a rapid progression, the hemodialysis membranes have been, in time, one of the key modifying points. In this paper will make a short presentation of the features of hemodialysis membranes and will point out aspects which need future research.

This paper presents the development of dynamically cured polymer composites and nanocomposites based on plastomer - PP (polypropylene) and EPDM elastomer (ethylene-propylene-diene-terpolymer) compatibilized and reinforced with nanometric particles-MMT (montmorillonite, chemically modified layered clay) in two stages, by extrusion-granulation and mixing. Nanoparticles increase the thermal resistance of dynamically cured polymer nanocomposites. By means of compatibilization and dynamic curing, elastomer particles - EPDM are more easily dispersed in the mixture. The materials obtained were tested physicomechanically (Melt Flow Index) and morpho-structurally (FT-IR and DSC).

Gene therapy represents a promising method for treating genetic disorders or diseases consisting in the transfer of genetic material (DNA) to cells in order to substitute or to slow down the evolution of the defective gene in cells. Theoretical models to predict DNA release are difficult to build in the classical approach of continuous and differentiable physical quantities, due to the high number of interdependent phenomena that occur simultaneous. The article presents a theoretical model based on the fractal theory of motions in the form of Scale Relativity Theory to describe nonlinear behaviors in gene therapy. Correlations of the theoretical model with experimental data are also observed.

Over time, anatomists have been concerned with the preservation of anatomical parts for a long time. Thus, in the modern era, both colouring and fixing substances, as well as plastic and corrosive materials have been used in the manufacture of corrosion and plastinated specimens. The ultimate aim was to make the dissected anatomical specimens as lasting and accurate as possible. Thus, parenchymal viscera, which have a certain tissue thickness, greater than in the tubular viscera, are more difficult to preserve and obviously to dissect. The time required to preserve those increases accordingly. In our study we have used 62 formalized adult human kidneys, belonging to 31 bilateral dissected bodies, different age and gender, 20 males and 11 females. We have removed all the kidneys from the renal fossa and we have made 23 corrosion casts, and 39 specimens have been plastinated. There have been dissected 30 structures considered as normal in size and morphological aspect and 9 have been preserved entirely because they did not fit within the normal physiological limits. All 39 kidneys have been undergone to S10 Biodur rubber silicone technique preservation.

Uterine sarcomas are rare but very aggressive gynecologic malignancies. The most frequent signs and symptoms at the moment of diagnosis include abnormal uterine bleeding or diffuse abdomino-pelvic pains while acute abdomen by uterine rupture is an uncommon situation. We present the case of a 72 year old patient who presented in emergency for diffuse abdominal pain and hypotension. An emergency laparotomy was performed and a ruptured uterine tumor with small bowel and sigmoidian serosal invasion and intra-peritoneal bleeding was found. The tumor was resected en bloc with total hysterectomy, bilateral adnexectomy, segmental enterectomy and sigmoidectomy, pelvic and para-aortic lymph node dissection. The histopathological and immunohistochemistry examination revealed a poorly differentiated sarcoma. Although it is a rare condition, a uterine sarcoma can rupture and cause hemoperitoneum; emergency surgery while respecting oncologic principles of complete resection is mandatory.