RESUMEN

The aim of this study is to design an effective hydrogel, which has good potential for application in the field of tissue regeneration. Ultimately, the polymeric biomaterial will be used as a bottom, non-cell adhering layer of a polymeric scaffold, which will inhibit the adhesion and proliferation of fibroblast cells. A series of terpolymer hydrogels were prepared from MMA/HPOEM/MePOEM monomers based on varying formulations. The gels were polymerized via free radical polymerization under UV and characterized by TGA, DSC and FTIR studies. Furthermore, the double bond conversion, gel content and swelling properties of the polymer were analyzed and correlated to its crosslinking density, which revealed details about the hydrogel's character. Finally, cell culture experiments were used to compare the UV-cured polymer to its thermally derived non-functionalized polymer of the same formulation. Inverted optical microscopy was used to demonstrate cell-resistance of both materials with respect to a control Tissue Culture PolyStyrene plate.

RESUMEN

Recent studies have indicated implementation of the CISM Program has impacted and reduced the cost of workers' compensation claims for stress related conditions and the number of lost work days (Ott, 1997; Western Management Consultants, 1996). Occupational health professionals need to be ready to develop and implement a comprehensive critical incident stress management process in anticipation of a major event. The ability to organize, lead, or administer critical incident stress debriefings for affected employees is a key role for the occupational health professional. Familiarity with these concepts and the ability to identify a critical incident enhances value to the business by mitigating the stress and impact to the workplace. Critical Incident Stress Management Systems have the potential for decreasing stress and restoring employees to normal life function--a win/win situation for both the employees and the organization.

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RESUMEN

Synthetic copolymers poly(epsilon-caprolactone-co-vinylphosphonic acid) (P(MDOVPA) and poly(epsilon-caprolactone-co-dimethylvinylphosphoester) (P(MDOVPE)) were used to prepare composites with polylactide (PLac) and hydroxyapatite (HAp). The P(MDOVPA) is used as filler in PLac films, as it has pendant functional groups P(O)(OH)2, providing nucleation sites for the deposition of HAp in simulated body fluid. HAp growth on P(MDOVPA) powder and PLac-P(MDOVPA) film was observed by Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray analysis (EDX) and X-ray diffraction (XRD). P(MDOVPE) and PLac blend are miscible, and the incorporation of hydrophilic P(MDOVPA) into PLac increased the hydrophilicity of the blend. Synthetic HAp was used to make multilayered, alternating organic-inorganic composites with porous PLac-P(MDOVPE) blends.

RESUMEN

Microparticles of poly(lactide) (PLac) and its copolymers with the amino acids, serine (P(Lac-Ser)), and aspartic acid (P(Lac-Asp)), respectively, were synthesized using the solvent evaporation microemulsion technique. Poly(vinyl alcohol) (PVA) was added as a non-ionic surfactant to stabilize the particles. The particle sizes are in the range of 200 nm. The surface of the particles was characterized by FTIR transmission spectroscopy under evacuation at room temperature and at 200 degrees C. Hydroxy groups originating from PVA exist on the surfaces of the particles and they were observed at 3506 cm(-1). Free hydroxy groups originating from the serine residue pendant to the copolymer P(Lac-Ser) backbone were observed at 3396 cm(-1). Also, free carboxylic acid groups pendant to the copolymer P(Lac-Asp) backbone, originating from the aspartic acid residue, were observed at 3387 cm(-1). The appearance of the free hydroxy or carboxylic acid groups in the IR spectra also showed that these hydrophilic functional groups moved to the surface of the particles in the process of microemulsion.

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RESUMEN

Rod-like hydroxyapatite was synthesized by precipitating calcium nitrate tetrahydrate and ammonium dibase phosphate in the presence of polyacrylic acid followed by hydrothermal treatment. Both polyacrylic acid and the hydrothermal treatment stabilised the hydroxyapatite.