Osteogenic differentiation of dura mater stem cells cultured in vitro on three-dimensional porous scaffolds of poly(epsilon-caprolactone) fabricated via co-extrusion and gas foaming.

A novel scaffold fabrication method utilizing both polymer blend extrusion and gas foaming techniques to control pore size distribution is presented. Seventy-five per cent of all pores produced using polymer blend extrusion alone were less than 50microm. Introducing a gas technique provided better control of pore size distribution, expanding the range from 0-50 to 0-350microm. Varying sintering time, annealing temperature and foaming pressure also helped to reduce the percentage of pore sizes below 50microm. Scaffolds chosen for in vitro cellular studies had a pore size distribution of 0-300microm, average pore size 66+/-17microm, 0.54+/-0.02% porosity and 98% interconnectivity, measured by micro-computed tomography (microCT) analysis. The ability of the scaffolds to support osteogenic differentiation for subsequent cranial defect repair was evaluated by static and dynamic (0.035+/-0.006ms(-1) terminal velocity) cultivation with dura mater stem cells (DSCs). In vitro studies showed minimal increases in proliferation over 28 days in culture in osteogenic media. Alkaline phosphatase expression remained constant throughout the study. Moderate increases in matrix deposition, as assessed by histochemical staining and microCT analysis, occurred at later time points, days 21 and 28. Although constructs cultured dynamically showed greater mineralization than static conditions, these trends were not significant. It remains unclear whether bioreactor culture of DSCs is advantageous for bone tissue engineering applications. However, these studies show that polycaprolactone (PCL) scaffolds alone, without the addition of other co-polymers or ceramics, support long-term attachment and mineralization of DSCs throughout the entire porous scaffold.

Strategies for self-management of HIV-related anxiety.

This study examines the frequency and effectiveness of commonly used strategies for self management of anxiety in an international sample of 502 participants from Norway (n=42, 8%), Taiwan (n=35, 7%), and the US (n=426, 85%). An activities checklist summarized into five categories of self-care behaviours including activities/thoughts, exercise, medications, complementary therapies, and substance use determined self-care behaviours. Ratings of frequency and effectiveness for each self-care activity were also included. Praying received the highest overall rating of effectiveness of any self-management strategies included in this study at 8.10 (scale 1 to 10), followed by meditation (7.37), exercising (7.32), using relaxation techniques (7.22), cooking (6.98), and walking (6.90). An analysis of effectiveness scores for each self-care strategy by country reflected a wide variation. The three most effective anxiety self-care strategies reported by participants from Norway included exercise (7.31), walking (6.96), and reading (6.44). Highest ratings of effectiveness by participants from Taiwan included talking with others with HIV (6.0), attending support groups (6.0), and exercising (6.0). US participants allocated highest ratings of effectiveness to complementary/alternative therapies, including praying (8.10), meditating (7.43), and using relaxation techniques (7.35). Regardless of the country, watching television and talking with family and friends were the two most frequently reported strategies. These strategies for self-management of HIV-related anxiety are important for clinicians to be aware of in the care of persons with HIV/AIDS.