Biocompatibility of biomimetic multilayered alginate-chitosan/ß-TCP scaffold for osteochondral tissue.

Biomimetic three-layered monolithic scaffold (TLS) intended for treatment of osteochondral defects was fabricated by using freeze drying method. The multilayered material was prepared with chitosan (C) and alginate (A) polyelectrolyte complex (CA/PEC) as a cartilaginous layer, a combination of CA/PEC (60 wt%) and ß-tricalcium phosphate (ß-TCP) (40 wt%) as an intermediate layer and a combination of CA/PEC (30 wt%) and ß-TCP (70 wt%) as a subchondral layer in order to mimic the inherent gradient structure of healthy osteochondral tissue. Characterization of the scaffolds was performed using Fourier transform infrared (FT-IR) spectroscopy analysis, swelling and scanning electron microscopy (SEM) tests. In vitro cytotoxicity assay with L929 cells and EpiDerm skin irritation test (SIT) using the EpiDerm reconstructed human epidermal (RHE) model were performed to analyze biocompatibility of the scaffolds. Characterization results showed that there were strong ionic interactions among chitosan, alginate and ß-TCP and the layers showed interconnected porous structure with different swelling ratios. The relative cell viability and SIT results were greater than 70% indicating that the scaffolds are considered nontoxic according to the International Organization for Standardization (ISO) standard. All results taken together, biomimetic TLS can be considered to be suitable for osteochondral applications.

Knowledge and attitudes of university students toward pandemic influenza: a cross-sectional study from Turkey.

BACKGROUND: During an influenza pandemic, higher education institutions with large populations of young adults can become serious outbreak centers. Since outbreak management is essential to disease control, we aimed to examine university students' knowledge of and attitudes toward the pandemic influenza A/H1N1 and vaccination and other preventive measures. METHODS: A cross-sectional study was conducted among 402 first year university students at Yeditepe University in Istanbul, Turkey between 1st and 30th of November 2009. Data regarding socio-demographic characteristics of the students, perceptions, level of knowledge and attitudes toward influenza pandemic and prevention measures were collected by means of a self-administered questionnaire. The questionnaire was distributed by the students affiliated with SANITAS, a university club of students in health related sciences. RESULTS: 25.1% (101/402) of the study group perceived their personal risk of influenza as "high", while 40.5% (163/402) perceived it as "moderate", 20.6% (107/402) viewed it as "low" and 7.7% (31/402) indicated that it was "unknown". The risk perception of males was significantly lower than that of females (p = 0.004) and the risk perception among the students of health sciences was significantly lower than that of students of other sciences (p = 0.037). Within the study group, 72.1% (290/402) indicated that their main information source regarding H1N1 was the mass media. Health sciences students tended to rely more on the internet as an information source than other students (p = 0.015). The vast majority (92.8%; 373/402) of those interviewed indicated that they would not be vaccinated. The major concerns regarding vaccination had to do with the safety and side effects of the vaccine. Most of the participants (343/402, 85.3%) were carrying out one of prevention measures and the vast majority believed that hand washing, face mask and quarantina were effective measures for prevention. CONCLUSION: The participants had enough knowledge about H1N1 pandemic about the disease although there were still gaps and confusions in some areas. In the future, when planning management strategies regarding pandemics or outbreaks in higher education institutions, new strategies should be developed to promote positive health behaviour among university students compatible with the international guidelines. Main information source is mass media, so it seems that new policies must be developed to attract attention of students to use different and more scientific-based information sources.