Surface modification and initial adhesion events for intestinal epithelial cells.

Rapid resealing of the mucosal epithelia is imperative following injuries to the small intestine because the mucosa is responsible for the adsorption of nutrients as well as providing a barrier to noxious agents present in the lumen. Tissue engineering may provide a possible solution for treating intestinal erosions, ulcerations, inflammatory bowel disease, and infection. Cell-biomaterial interaction is a critical component in tissue engineering that can determine the success of the tissue construct. Cell-biomaterial interactions can be enhanced by various types of surface modification, which promote integrin ligation leading to increased cell function. In order to relate the effect of surface adhesion molecules to signaling events and macroscopic cell response, an intestinal epithelial cell line, IEC-6, was plated on fibronectin (receptor-mediated) and poly-L-lysine (non-specific) surfaces. Focal adhesion kinase (FAK) phosphorylation, cell spreading, and cell adhesion strength were measured. Results showed increases in FAK phosphorylation generally corresponded to increases in cell spreading and adhesion strength for IEC-6 cells. Therefore, in a simplified system, initial adhesion and signaling mechanisms appeared to correspond to subsequent physical responses in IEC-6 cells relevant to tissue engineering applications.

Quantitative analyses of Streptococcus mutans biofilms with quartz crystal microbalance, microjet impingement and confocal microscopy.

Microbial biofilm formation can be influenced by many physiological and genetic factors. The conventional microtiter plate assay provides useful but limited information about biofilm formation. With the fast expansion of the biofilm research field, there are urgent needs for more informative techniques to quantify the major parameters of a biofilm, such as adhesive strength and total biomass. It would be even more ideal if these measurements could be conducted in a real-time, non-invasive manner. In this study, we used quartz crystal microbalance (QCM) and microjet impingement (MJI) to measure total biomass and adhesive strength, respectively, of S. mutans biofilms formed under different sucrose concentrations. In conjunction with confocal laser scanning microscopy (CLSM) and the COMSTAT software, we show that sucrose concentration affects the biofilm strength, total biomass, and architecture in both qualitative and quantitative manners. Our data correlate well with previous observations about the effect of sucrose on the adherence of S. mutans to the tooth surface, and demonstrate that QCM is a useful tool for studying the kinetics of biofilm formation in real time and that MJI is a sensitive, easy-to-use device to measure the adhesive strength of a biofilm.

As the Third World turns.

PIP: Throughout the 3rd World, family planners have turned to television in order to spread their message. Combining education and entertainment in the form of advertisements and soap operas, television offers a way to provide clear and memorable information about an otherwise sensitive issue. In 1977, Mexico's Miguel Sabido developed the idea of using television as a means of social instruction. His initial soap opera dealt with adult literacy, and the success of that program led him to develop a show focusing on family planning called "Come Along with Me." Following the airing of this soap opera, attendance to family planning clinics increased by 32%. Since then, Mexico has produced a series of soap operas dealing with sex education, women's status, and the treatment of children. Soon, Mexican viewers will see a soap opera addressing the issue of AIDS. Family planners in other countries have also begun employing television. Conventional communication methods require trained counselors travelling villages, and most often, those most in need of family planning are the most difficult to reach. But over the last 10 years, the number of televisions in the Third World has doubled, and there is now approximately 1 television for every 12 people in the developing nations. In Turkey, advertisements have been used to promote modern methods of contraception. In Brazil, vasectomy has been one of the topics of ad campaigns. Mexico, the Philippines, and Nigeria have also experimented with the use of music videos. Nigeria has already had great success in integrating family planning themes to an already existing variety show. Family planning visits have increased by 47%. International agencies have recognized the value of television and have provided financial support.^ieng

Speech performance, dysphagia and oral reflexes in cerebral palsy.

The adequacy of biting, sucking, swallowing, and chewing as well as the presence or absence of nine infantile oral reflexes were assessed in 60 cerebral-palsied individuals. The effect of the asymmetric tonic neck reflex and the Moro reflex on the infantile oral reflexes was also studied. There was a trend for subjects with more adequate feeding skills to achieve higher levels of overall speech proficiency and articulatory competency, but this trend was not completely systematic. Fifteen subjects displayed abnormal oral reflexes, but these reflexes could not be elicited consistently. The effect of the ATNR and Moro reflex on the oral reflexes seemed limited. Results generally supported the value of the widespread prescription of improving feeding in cerebral palsy, but the need to modify abnormal oral reflexes received less support. The question of using prespeech oromotor training to reduce possible future dysarthria is discussed in terms of the findings.