For developing, these composites, the hydrogel matrices are synthesized first by polymerizing acrylamide in the presence of poly(vinyl sulfonic acid sodium salt) and a trifunctional crosslinker (2,4,6-triallyloxy 1,3,5-triazine, TA) using redox initiating system (ammonium persulphate/TMEDA). Silver nanoparticles are generated throughout the hydrogel networks using in situ method by incorporating the silver ions and subsequent reduction with sodium Compound Library high throughput borohydride. Curcumin
loading into hydrogel-silver nanoparticles composite is achieved by diffusion mechanism. A series of hydrogel-silver nanoparticle-curcumin composites are developed and are characterized by using Fourier transform infrared (FTIR) and UV-visible (UV-vis) spectroscopy, X-ray diffraction, thermal analyses, as well as
scanning and transmission electron microscopic (SEM/TEM) methods. An interesting arrangement of Selleckchem 17DMAG silver nanoparticles i.e., a shining sun shape (ball) (similar to 5 nm) with apparent smaller grown nanoparticles (similar to 1 nm) is observed by TEM. The curcumin loading and release characteristics are performed for various hydrogel composite systems. A comparative antimicrobial study is performed for hydrogel-silver nanocomposites and hydrogel-silver nanoparticle-curcumin composites. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 784-796, 2011″
“Study Design. In vitro biomechanical study.
Objective. To measure the effect that off-axis vertebral
loading has on the stiffness and failure load of vertebrae.
Summary of Background Data. Adjacent level vertebral fractures not only are common in patients who received a vertebroplasty treatment but also occur in patients with conservatively treated wedge fractures. The wedge-like deformity, which is present in both groups, changes the spinal alignment. The load of vertebrae adjacent to the fractured vertebra will change from perpendicular to the endplate to a more shearing, off-axis, load. This change may induce a higher fracture risk for vertebrae adjacent to wedge-like deformed vertebrae.
Methods. Twenty vertebrae, harvested from one osteopenic cadaver VX809 spine and three osteoporotic cadaver spines, were loaded until failure. The vertebrae were loaded either perpendicular to the upper endplate, representing vertebrae in a spine without wedge fractures (0 degrees group, n = 10), or at an angle of 20 degrees, representing vertebrae adjacent to a wedge fracture (20 degrees groups, n = 10). Vertebral failure load and stiffness were the most important outcome measures.
Results. The failure load was significantly higher (P = 0.028) when tested at 0 degrees (2854 N, SD = 622 N), compared with vertebrae tested at 20 degrees (2162 N, SD = 670 N). Vertebrae were also significantly stiffer (P < 0.001) when tested at 0 degrees (4017 N/mm, SD = 970 N/mm) than those tested at 20 degrees (2478 N/mm, SD = 453 N/mm).