Nanoparticles are increasingly being recognized for their potential utility in biological applications including nanomedicine. Here we examine the response of normal human cells to ZnO nanoparticles under different signaling environments and compare it to the response of cancerous cells. ZnO nanoparticles exhibit a strong preferential ability to kill cancerous T cells (∼28-35×) compared to normal cells. Interestingly, the activation state of the cell contributes toward nanoparticle toxicity, as resting T cells display a relative resistance while cells stimulated through the T cell receptor and CD28 costimulatory pathway show greater toxicity in direct relation to the level of activation. Mechanisms of toxicity appear to involve the generation of reactive oxygen species, with cancerous T cells producing higher inducible levels than normal T cells. In addition, nanoparticles were found to induce apoptosis and the inhibition of reactive oxygen species was found to be protective against nanoparticle induced cell death. The novel findings of cell selective toxicity, towards potential disease causing cells, indicate a potential utility of ZnO nanoparticles in the treatment of cancer and/ or autoimmunity.

Honey mainly consists of sugars and water. Apart from sugars, honey also contains several vitamins, especially B complex and vitamin C, together with a lot of minerals. Some of the vitamins found in honey include ascorbic acid, pantothenic acid, niacin and riboflavin; while minerals such as calcium, copper, iron, magnesium, manganese, phosphorus, potassium and zinc are also present. Honey has been used for its healing, nutritional and therapeutic properties since ancient times. Its antibacterial potentials even against multi-drug resistant bacteria, such as Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacterbaumanni have been proved. Honey is well known for its anti-inflammatory and antioxidant capacities, which may be useful for the prevention of chronic inflammatory process like atherosclerosis, diabetes mellitus and cardiovascular diseases. The antibacterial, antiinflammatory and antioxidant properties of honey will be reviewed here.

Winston developed a technique known as "cerebral corticectomy" in an effort to benefit from the success of AH in controlling intractable

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A series of novel cross-linked highly quaternized chitosan and quaternized poly (vinyl alcohol) membranes were successfully synthesized to be applied in alkaline direct ethanol fuel cells. Cross-linking was accomplished using two different cross-linking agents and an additional thermal process to improve both chemical and thermal properties. Equivalent blends of chitosan and poly (vinyl alcohol) membranes with various degrees of cross-linking were prepared by using different amounts of glutaraldehyde and ethylene glycol diglycidyl ether as cross-linkers. To investigate their applicability in direct ethanol fuel cells, the membranes were characterized in terms of their structural properties, chemical, thermal and alkaline stability, ion transport and ionic properties using following methods: Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, scanning electron microscopy, thermogravimetric analysis, water uptake by mass change, ethanol permeability in the diffusion cell, back titration method (ion exchange capacity) and electrochemical impedance spectroscopy (anion conductivity). Despite the high degree of quaternization of the applied materials and regardless of the thin film thickness of the blend membranes, the novel cross-linked products displayed outstanding mechanical stability. The lower crosslinked membranes exhibited the best transport and ionic properties with a high anion conductivity of 0.016 S cm-1 and a high ion exchange capacity of 1.75 meq g-1 , whereas membranes with a higher degree of cross-linking performed superior in terms of reduced ethanol permeability of 3.30•10-7 cm 2 s-1 at 60°C. The blend membranes-chemically and thermally cross-linked-provide excellent thermal stability with an onset degradation temperature above 280°C and superb alkaline stability in 1.0 M KOH at 60°C for 650 h. Therefore, these composite membranes exhibit high potential for application as alkaline electrolytes in fuel cells.