Study of Nanohydroxyapatite Coatings Prepared by the Electrophoretic Deposition Method at Various Voltage and Time Parameters.

The aim of the work is to compare the properties of nanohydroxyapatite coatings obtained using the electrophoretic deposition method (EDP) at 10 V, 20 V, and 30 V, and with deposit times of 2 and 5 min. The primary sedimentation was used to minimize the risk of the formation of particle agglomerates on the sample surface. Evaluation of the coating was performed by using a Scanning Electron Microscope (SEM), Energy-Dispersive Spectroscopy (EDS), Atomic Force Microscopy (AFM), optical profilometer, drop shape analyzer, and a nanoscratch tester. All of the coatings are homogeneous without any agglomerates. When low voltage (10 V) was used, the coatings were uniform and continuous regardless of the deposition time. The increase in voltage resulted in the formation of cracks in the coatings. The wettability test shows the hydrophilic behavior of the coatings and the mean contact angle values are in the range of 20-37°. The coatings showed excellent adhesion to the substrate. The application of a maximum force of 400 mN did not cause delamination in most coatings. It is concluded that the optimal coating for orthopedic implants (such as hip joint implants, knee joint implants or facial elements) is obtained at 10 V and 5 min because of its homogeneity, and a contact angle that promotes osseointegration and great adhesion to the substrate.

Antimicrobial and Antiproliferative Coatings for Stents in Veterinary Medicine-State of the Art and Perspectives.

Microbial colonization in veterinary stents poses a significant and concerning issue in veterinary medicine. Over time, these pathogens, particularly bacteria, can colonize the stent surfaces, leading to various complications. Two weeks following the stent insertion procedure, the colonization becomes observable, with the aggressiveness of bacterial growth directly correlating with the duration of stent placement. Such microbial colonization can result in infections and inflammations, compromising the stent's efficacy and, subsequently, the animal patient's overall well-being. Managing and mitigating the impact of these pathogens on veterinary stents is a crucial challenge that veterinarians and researchers are actively addressing to ensure the successful treatment and recovery of their animal patients. In addition, irritation of the tissue in the form of an inserted stent can lead to overgrowth of granulation tissue, leading to the closure of the stent lumen, as is most often the case in the trachea. Such serious complications after stent placement require improvements in the procedures used to date. In this review, antibacterial or antibiofilm strategies for several stents used in veterinary medicine have been discussed based on the current literature and the perspectives have been drawn. Various coating strategies such as coating with hydrogel, antibiotic, or other antimicrobial agents have been reviewed.

Preparation and Characterization of Diamond-like Carbon Coatings for Biomedical Applications-A Review.

Diamond-like carbon (DLC) films are generally used in biomedical applications, mainly because of their tribological and chemical properties that prevent the release of substrate ions, extend the life cycle of the material, and promote cell growth. The unique properties of the coating depend on the ratio of the sp3/sp2 phases, where the sp2 phase provides coatings with a low coefficient of friction and good electrical conductivity, while the share of the sp3 phase determines the chemical inertness, high hardness, and resistance to tribological wear. DLC coatings are characterized by high hardness, low coefficient of friction, high corrosion resistance, and biocompatibility. These properties make them attractive as potential wear-resistant coatings in many compelling applications, including optical, mechanical, microelectronic, and biomedical applications. Another great advantage of DLC coatings is that they can be deposited at low temperatures on a variety of substrates and can thus be used to coat heat-sensitive materials, such as polymers. Coating deposition techniques are constantly being improved; techniques based on vacuum environment reactions are mainly used, such as physical vapor deposition (PVD) and chemical vapor deposition (CVD). This review summarizes the current knowledge and research regarding diamond-like carbon coatings.

Influence of Different Nanometals Implemented in PMMA Bone Cement on Biological and Mechanical Properties.

Cemented arthroplasty is a common process to fix prostheses when a patient becomes older and his/her bone quality deteriorates. The applied cements are biocompatible, can transfer loads, and dampen vibrations, but do not provide antibacterial protection. The present work is aimed at the development of cement with antibacterial effectivity achieved with the implementation of nanoparticles of different metals. The powders of Ag, Cu with particles size in a range of 10-30 nm (Cu10) and 70-100 nm (Cu70), AgCu, and Ni were added to PMMA cement. Their influence on compression strength, wettability, and antibacterial properties of cement was assessed. The surface topography of samples was examined with biological and scanning electron microscopy. The mechanical properties were determined by compression tests. A contact angle was observed with a goniometer. The biological tests included an assessment of cytotoxicity (XTT test on human cells Saos-2 line) and bacteria viability exposure (6 months). The cements with Ag and Cu nanopowders were free of bacteria. For AgCu and Ni nanoparticles, the bacterial solution became denser over time and, after 6 months, the bacteria clustered into conglomerates, creating a biofilm. All metal powders in their native form in direct contact reduce the number of eukaryotic cells. Cell viability is the least limited by Ag and Cu particles of smaller size. All samples demonstrated hydrophobic nature in the wettability test. The mechanical strength was not significantly affected by the additions of metal powders. The nanometal particles incorporated in PMMA-based bone cement can introduce long-term resistance against bacteria, not resulting in any serious deterioration of compression strength.

Initial Field Validation of Poroelastic Pavement Made with Crumb Rubber, Mineral Aggregate and Highly Polymer-Modified Bitumen.

Tire/road noise in most driving conditions dominates other sources of traffic noise. One of the most efficient ways of reducing tire/road noise is to use the so-called "low noise pavement". According to numerous studies, at present, poroelastic road pavement that is composed of rubber and mineral aggregate and polyurethane or bituminous binder gives the best noise reduction up to 12 dB. Unfortunately, there are many problems with making durable poroelastic pavements. This article presents the first results of a project that is executed in Poland and aims at the development of a durable, low noise poroelastic pavement based on polymer-modified asphalt binder called Safe, Eco-friendly POroelastic Road Surface (SEPOR). Two test sections were built in 2019 to test the production technology and performance of the SEPOR pavement. It is observed that some of the problems with previous poroelastic materials were mainly eliminated (especially delamination from the base layer and raveling) but noise reduction is a little less than expected (up to 9 dB). Rolling resistance for car tires is acceptable and fire properties (damping of spill fuel fires, toxic gas emission) are very good.

Implant system for treatment of the orbital floor defects of blowout fractures in the maxillofacial region using polypropylene yarn and bioactive bone cement.

Fractures in the craniofacial region are a serious problem in terms of treatment. The most reasonable solution is the use of individual implants dedicated to a specific patient. The aim of this study was to develop the implant system specifically for treatment of the orbital floor defects of blowout fractures of maxillofacial region, using polypropylene yarn and bone cement. Three types of bone cement were used to fix the polypropylene yarn: unmodified, antibiotic-loaded, and modified with nanometals. The following research was carried out: selection of cement production parameters, assessment of the curing time, measurement of polymerization temperature, an analysis of microstructure and surface topography, evaluation of wettability, measurement of microhardness, and studies of bactericidal effectiveness. The research confirms the possibility of using bone cement and polypropylene yarn for an individual implant, dedicated to the fractures treatment in the maxillofacial region. Moreover, the bactericidal properties of the proposed modifications for bone cement have been verified; hence, bioactive cements are recommended for use in the case of infectious complications.

Surgical Site Infection after Breast Surgery: A Retrospective Analysis of 5-Year Postoperative Data from a Single Center in Poland.

Background and Objectives: Surgical site infection (SSI) is a significant complication of non-reconstructive and reconstructive breast surgery. This study aimed to assess SSI after breast surgery over five years in a single center in Poland. The microorganisms responsible for SSI and their antibiotic susceptibilities were determined. Materials and Methods: Data from 2129 patients acquired over five years postoperatively by the Department of Surgical Oncology, Medical University of Gdansk in Poland were analyzed. Results: SSI was diagnosed in 132 patients (6.2%) and was an early infection in most cases (65.2%). The incidence of SSI was highest in patients who underwent subcutaneous amputation with simultaneous reconstruction using an artificial prosthesis (14.6%), and breast reconstruction via the transverse rectus abdominis muscle (TRAM) flap method (14.3%). Gram-positive bacteria were responsible for SSI in most cases (72.1%), and these were mainly Staphylococcus strains (53.6%). These strains were 100% susceptible to all beta-lactam antibiotics (except penicillin) but were less susceptible to macrolides and lincosamides. Conclusions: SSI is a serious problem, and attention should be focused on its prevention. Reconstruction using an artificial prosthesis or via the TRAM flap method is connected to increased SSI incidence. Further studies are required to prevent SSI following breast surgery.

Antibacterial Activity and Cytocompatibility of Bone Cement Enriched with Antibiotic, Nanosilver, and Nanocopper for Bone Regeneration.

Bacterial infections due to bone replacement surgeries require modifications of bone cement with antibacterial components. This study aimed to investigate whether the incorporation of gentamicin or nanometals into bone cement may reduce and to what extent bacterial growth without the loss of overall cytocompatibility and adverse effects in vitro. The bone cement Cemex was used as the base material, modified either with gentamicin sulfate or nanometals: Silver or copper. The inhibition of bacterial adhesion and growth was examined against five different bacterial strains along with integrity of erythrocytes, viability of blood platelets, and dental pulp stem cells. Bone cement modified with nanoAg or nanoCu revealed greater bactericidal effects and prevented the biofilm formation better compared to antibiotic-loaded bone cement. The cement containing nanoAg displayed good cytocompatibility without noticeable hemolysis of erythrocytes or blood platelet disfunction and good viability of dental pulp stem cells (DPSC). On the contrary, the nanoCu cement enhanced hemolysis of erythrocytes, reduced the platelets aggregation, and decreased DPSC viability. Based on these studies, we suggest the modification of bone cement with nanoAg may be a good strategy to provide improved implant fixative for bone regeneration purposes.