Incorporating Opioids into Micro - to Nano - Structurally Optimized Silica Xerogel Controlled Release Delivery Systems Prevents Abuse

Analgesics is a multibillion dollar worldwide industry. Oxycodone, an opioid, is currently administered using controlled release tablets; although this has resulted in considerable control over pain management, the controlledrelease tablets have been abused by drug users. Measures to curb illicit use of the drug have not been successful, to date. This study proposes that by incorporating the medicine into a micro- to nano-structurally optimized delivery material, release concentrations that cannot exceed therapeutic target levels will be achieved and therefore, curbing its misuse, even when the carrier material is crushed. Using Dextromethorphan (Dextro) as a model drug, silica xerogels (sol-gels) were synthesized by mixing tetramethoxysilane, Deionized water and HCl, in addition to Dextro-methanol solution. Different drug loads and water-to-alkoxide ratios were observed to alter the micro- and nanostructurural properties. Different particle sizes were produced by crushing the xerogel discs, after which they were sieved and immersed in 5mg/ml PBS solution. Concentration of released Dextro was measured spectrophotometrically at 280 nm. The effect of particle size on in vitro release of Dextro from xerogels, as a function of immersion time, demonstrated that both micro- to nano-sized particles exhibited timedependent release of Dextro. Although the release from nano-sized particles was noticeably faster than from the micro-sized ones, they did not show any burst release. Data obtained demonstrate that synthesizing a delivery system capable of achieving the controlled-release of therapeutically relevant doses and misuse resistance are attainable

Exploring the Level of Computer Literacy for Candidates in Higher Education: ICDL Programme at Bahrain Polytechnic

Bahrain Polytechnic is a Higher Education technical institution established in 2008 (by Royal Decree No. 65 for the year 2008). Its main mission is to supply the Bahraini economy with a skilled Bahraini labour force aiming to contribute to economic growth and diversification. The Polytechnic ensures that its values of excellence, learning and innovation are achieved by designing curricula that meet international standards as well as national and individual needs through continuous consultations with the industries and international education institutions. The development of computer and technological literacy is a significant predictor for success in the workplace and is also one of the key skills that the polytechnic provides through its programmes to students and faculty. This paper explores how computer literacy and skills are acquired by educators and students through International Computer Driving License (ICDL) tools employed at Bahrain Polytechnic. The study also considers the challenges that hinder learners from completing the requirements of ICDL.  If adequate numbers of faculty and students have already learned basic computer skills, then the question facing the polytechnic is if computer literacy should continue to be taught at all levels. To answer this question, ICDL tests were administered to ascertain the computer literacy level of existing faculty and students. The results of the tests will determine which ICDL tests students and faculty should be placed on in order to address their computer literacy needs

Elastic Membrane That Undergoes Mechanical Deformation Enhances Osteoblast Cellular Attachment and Proliferation

The main objective of this paper was to investigate the effect of transmission of force on bone cells that were attached to a deformable membrane. We functionalized a silastic membrane that measured 0.005 inches thickness and coated it with an extra cellular matrix (ECM) protein, fibronectin (FN). MC3T3-E1 osteoblast-like cells were cultured on the functionalized FN-coated membrane after which cell attachment and proliferation were evaluated. We observed an immediate attachment and proliferation of the bone cells on the functionalized membrane coated with FN, after 24 hours. Upon application of a mechanical force to cells cultured on the functionalized silicone membrane in the form of a dynamic equibiaxial strain, 2% magnitude; at 1-Hz frequency for 2 h, the osteoblast cells elicited slightly elevated phalloidin fluorescence, suggesting that there was reorganization of the cytoskeleton. We concluded from this preliminary data obtained that the engineered surface transduced applied mechanical forces directly to the adherent osteoblast cells via integrin binding tripeptide receptors, present in the FN molecules, resulting in the enhanced cellular attachment and proliferation

Effect of surface activated poly(dimethylsiloxane) on fibronectin adsorption and cell function

Cell function on biomaterials may depend on surface chemistry and concentration (as well as conformation) of protein molecules. To understand the interplay between these two effects, fibronectin (Fn) was physi-sorbed on a smooth, activated poly(dimethylsiloxane), films spun cast on silicon wafers. Contact angle goniometry, ellipsometry, Atomic force microscopy and Rutherford backscattering spectrometry were used to characterize the nanoscale roughness and thickness of the films. The films were activated by exposure to 30 min ultraviolet ozone radiation. Water contact angle measurements indicated higher hydrophobicity (\u3e 100o) prior to surface activation. Tapping mode AFM scans showed that the activation process produced a rougher substrate (Ra \u3e 0.50 nm). Fibronectin surface coverage after incubating PDMS in 2.5µg/mL of Fn was significantly higher than on non-activated surface, possibly due to favorable hydrophobic interactions between PDMS and Fn. To investigate the effect of surface activation on MC3T3-E1 osteoblast-like cells, cell spreading on PDMS and activated PDMS (30 min) coated with 2.5 µg/mL Fn was studied. Cells plated on the activated Fn-coated PDMS, for 15 min, in DMEM (with serum) showed higher cell attachment. Cell spreading after 72 h plating was clearly favored on the hydrophilic substrates as well. The increase in cell area is attributed to favorable conformational changes in absorbed Fn molecules on these substrates

Cell Culture on MEMS Platforms: A Review

Microfabricated systems provide an excellent platform for the culture of cells, and are an extremely useful tool for the investigation of cellular responses to various stimuli. Advantages offered over traditional methods include cost-effectiveness, controllability, low volume, high resolution, and sensitivity. Both biocompatible and bioincompatible materials have been developed for use in these applications. Biocompatible materials such as PMMA or PLGA can be used directly for cell culture. However, for bioincompatible materials such as silicon or PDMS, additional steps need to be taken to render these materials more suitable for cell adhesion and maintenance. This review describes multiple surface modification strategies to improve the biocompatibility of MEMS materials. Basic concepts of cell-biomaterial interactions, such as protein adsorption and cell adhesion are covered. Finally, the applications of these MEMS materials in Tissue Engineering are presented.Institute of Bioengineering and Nanotechnology (Singapore)Singapore. Biomedical Research CouncilSingapore. Agency for Science, Technology and ResearchSingapore. Agency for Science, Technology and Research (R-185-001-045-305)Singapore. Ministry of EducationSingapore. Ministry of Education (Grant R-185- 000-135-112)Singapore. National Medical Research CouncilSingapore. National Medical Research Council (Grant R-185-000-099-213)Jassen Cilag (Firm)Singapore-MIT Alliance (Computational and Systems Biology Flagship Project)Global Enterprise for Micro-Mechanics and Molecular Medicin

Setting shrinkage strains of chemical-cured glass ionomer-based dental restorative materials

Shrinkage strains are exhibited by the current formulations of chemical-cured dental restorative systems. In resin-modified glass ionomer systems, these have been linked to filler contents, types and quantity of monomer. Post-gelation rigid contraction that follows onset of cure leading to marginal defects is a clinically significant factor, although flow is noted to compensate for shrinkage effects during pre-gelation phase. The bonded-disk technique was employed to study the shrinkage strains of chemical-cured and light-activated glass polyalkenoate-based cements at two clinical temperatures of 37EC and 60EC over a period of 2 hours. Magnitudes of shrinkage strains obtained were subjected to one-way ANOVA and Schefe's 0.5 significant level statistical analysis. The time-dependent shrinkage strain data characteristic of the materials indicated a linear initial rigid and rapid contraction, which is appropriately represented by the Kohlrausch-Williams-Watts stretched exponential decay curve. The kinetics of shrinkage was expressed by the overall time constant and the initial contraction strains at 30 s, following the onset of cure. Data obtained after 15 minutes up to 2 hours indicated high contraction strains at 60EC compared to that at the intra-oral temperature, 37EC. There is a relatively slow development of contraction strains in glass ionomer-based systems compared to resin-based ones. This is, however, a positive quality for the glassy materials in their use as marginal seals. Nevertheless, contraction strains in dental restorative systems with their destructive shrinkage stresses remain unresolved. JOURNAL OF THE GHANA SCIENCE ASSOCIATION Volume 2 No. 3 (2000) pp. 103-11