Controlling multi-function of biomaterials interfaces based on multiple and competing adsorption of functional proteins.

Multifunctional biomaterial surfaces can be created by controlling the competing adsorption of multiple proteins. To demonstrate this concept, bone morphogenetic protein 2 (BMP-2) and fibronectin were adsorbed to the hydrophobic surface of polychloro-para-xylylene. The resulting adsorption properties on the surface depended on the dimensional and steric characteristics of the selected protein molecule, the degree of denaturation of the adsorbed proteins, the associated adsorption of interphase water molecules within the protein layers, and the aggregation of proteins in a planar direction with respect to the adsorbent surface. Additionally, a defined surface composition was formed by the competing adsorption of multiple proteins, and this surface composition was directly linked to the composition of the protein mixture in the solution phase. Although the mechanism of this complex competing adsorption process is not fully understood, the adsorbed proteins were irreversibly adsorbed and were unaffected by the further adsorption of homologous or heterologous proteins. Moreover, synergistic biological activities, including cell osteogenesis and proliferation independently and specifically induced by BMP-2 or fibronectin, were observed on the modified surface, and these biological activities were positively correlated with the surface composition of the multiple adsorbed proteins. These results provide insights and important design parameters for prospective biomaterials and biointerfaces for (multi)functional modifications. The ability to control protein/interface properties will be beneficial for the processing of biomaterials for clinical applications and industrial products.

Enhanced bone morphogenic property of parylene-C.

The ability to induce osteointegration was introduced to a parylene-C surface via the simple and intuitive process of protein adsorption mediated by hydrophobic interactions. In this way, bone morphogenetic protein (BMP)-2, fibronectin, and platelet-rich plasma (PRP) could be immobilized on parylene-C surfaces. This approach alleviates concerns related to the use of potentially harmful substances in parylene-C modification processes. The adsorbed protein molecules were quantitatively characterized with respect to adsorption efficacy and binding affinity, and the important biological activities of the proteins were also examined using both early and late markers of osteogenetic activity, including alkaline phosphatase expression, calcium mineralization and marker gene expression. Additionally, the adsorbed PRP exhibited potential as a substitute for expensive recombinant growth factors by effectively inducing comparable osteogenetic activity. In addition to the excellent biocompatibility of parylene-C and its ability to coat a wide variety of substrate materials, the modification of parylene-C via protein adsorption provides unlimited possibilities for installing specific biological functions, expanding the potential applications of this material to include various biointerface platforms.

Accurate quantitative measurement of lunate uncovering ratio--is Gilula's semiquantitative test reliable?

The Gilula's test suggests the presence of ulnocarpal translation when 50% or more of the lunate lies medial to the ulnar edge of radius. The purpose of this study was to examine the reliability of this semiquantitative test as there was inconsistency between the previous publications in regarding 50% as the cutoff value for the normal lunate uncovering ratio (LUR). We utilized the Picture Archiving and Communication System to investigate radiographs of 299 normal adult wrists and emphasized defined radiographic landmarks for accurate quantitative measurement. Our mean LUR was 35%(SD8) with a range of 8 to 49%. Therefore we re-affirmed the reliability of the Gilula's test since none of our normal wrists had a LUR of 50% or greater.

The effectiveness of hospital-based diabetes case management: an example from a northern Taiwan regional hospital.

The aim of this study was to design, implement and evaluate disease outcomes at a regional hospital- based case management program of care for patients with type 2 diabetes. A medical team and practice guidelines were established in line with the health insurance strategy of Taiwan's Bureau of National Health Insurance (BNHI) and American Diabetes Association (ADA) Standards of Care for Diabetes (2003 edition). Also, a set of self-care booklets was designed suitable for use by the subject group. The study was prospective and followed the patients from enrollment to one year. Patient outcomes were determined based on laboratory examinations and recorded self-care behavior. Data were collected at enrollment and over 4 follow-up times within a one year period. Generalized Estimating Equation (GEE) multiple linear regression and logistic regression were used for repeated measurements and adjustments of the effects of specific prognostic factors. Sixty subjects diagnosed with type 2 diabetes (mean duration 3.25 years) were recruited. All participants were married with a mean age of 52.5 years. A majority (58.3%) was male and 65% were ethnic Hakka. Self-care knowledge and behavior accomplishment rates were: taking medications by oneself, 91.3% (knowing medicines, 25.4%); hypoglycemia management, 23.3%; monitoring blood sugar, 46.7%; exercise, 35.8%; diet management, 51.7% and foot care, 92.8%. Significantly improved ADA diabetes care standard items included HbA1C (p< .0001), fasting glucose (p< .01) and triglycerides (p< .05). The study incorporated evidence-based guidelines, public health insurance strategies and self-care booklets into a protocol to provide comprehensive care. The implemented diabetes program achieved diabetes care goals and improved patient self-care.