Microstructure and Properties of Polyhydroxybutyrate-Chitosan-Nanohydroxyapatite Composite Scaffolds

Polyhydroxybutyrate-chitosan-hydroxyapatite (PHB-CHT-HAP) composite scaffolds were prepared by the precipitation of biopolymer-nanohydroxyapatite suspensions and following lyophilisation. The propylene carbonate and acetic acid were used as the polyhydroxybutyrate and chitosan solvents, respectively. The high porous microstructure was observed in composites and the macroporosity of scaffolds (pore sizes up to 100 μm) rose with the chitosan content. It was found the reduction in both the PHB melting (70°C) and thermal degradation temperatures of polyhydroxybutyrate and chitosan biopolymers in composites, which confirms the mutual ineraction between polymers and the decrease of PHB lamellar thickness. No preferential preconcentration of individual biopolymers was verified in composites, and the compressive strengths of macroporous PHB-CHT-HAP scaffolds were approximately 2.5 MPa. The high toxic fluorinated cosolvents were avoided from the preparation process

Digital Factory – theory and practice

The paper focuses on the research & development of the Digital Factory solutions for industry. The developed methodology and solution of Factory Mock Up (FMU) is presented. The results of research and development cover design of assembly system, its processes, simulations model, ergonomic analysis etc. In the paper are presented the solutions developed in the framework of co-operation with industrial partners like Volkswagen Slovakia, Thyssen Krupp – PSL, Whirlpool. The advantages, restrictions and way of utilization of Digital Factory solutions are also shown in the paper

A novel technique for arthroscopically assisted femoral bone tunnel grafting in two-stage ACL revision

This technique of bone grafting of improperly positioned bone tunnels in failed ACL reconstructions is technically straightforward and effective in challenging cases

Beginning Hip Arthroscopy: Indications, Positioning, Portals, Basic Techniques, and Complications

Hip arthroscopy is becoming increasingly popular for the diagnosis and treatment of hip pathology, and the indications continue to evolve. The two most common approaches are the supine and lateral decubitus position. Both approaches can be performed effectively; however, each approach has its own benefits and drawbacks. In this review we will describe the indications for hip arthroscopy, the pros and cons of each approach, and the necessary equipment, portals, portal placement, commercially available distraction devices, and complications. © 2007 Arthroscopy Association of North America

Transient and Prolonged Response of Chicken Cecum Mucosa to Colonization with Different Gut Microbiota

In this study we determined protein and gene expression in the caeca of newly hatched chickens inoculated with cecal contents sourced from hens of different ages. Over 250 proteins exhibited modified expression levels in response to microbiota inoculation. The most significant inductions were observed for ISG12-2, OASL, ES1, LYG2, DMBT1-L, CDD, ANGPTL6, B2M, CUZD1, IgM and Ig lambda chain. Of these, ISG12-2, ES1 and both immunoglobulins were expressed at lower levels in germ-free chickens compared to conventional chickens. In contrast, CELA2A, BRT-2, ALDH1A1, ADH1C, AKR1B1L, HEXB, ALDH2, ALDOB, CALB1 and TTR were expressed at lower levels following inoculation of microbiota. When chicks were given microbiota preparations from different age donors, the recipients mounted differential responses to the inoculation which also differed from the response profile in naturally colonised birds. For example, B2M, CUZD1 and CELA2A responded differently to the inoculation with microbiota of 4- or 40-week-old hens. The increased or decreased gene expression could be recorded 6 weeks after the inoculation of newly hatched chickens. To characterise the proteins that may directly interact with the microbiota we characterised chicken proteins that co-purified with the microbiota and identified a range of host proteins including CDD, ANGPTL6, DMBT1-L, MEP1A and Ig lambda. We propose that induction of ISG12-2 results in reduced apoptosis of host cells exposed to the colonizing commensal microbiota and that CDD, ANGPTL6, DMBT1-L, MEP1A and Ig lambda reduce contact of luminal microbiota with the gut epithelium thereby reducing the inflammatory response