Efficient sensing of single viruses and nanoparticles by nanomechanical sensors integrated with ion lenses

Nanoelectromechanical Systems (NEMS) resonators can be used to detect, weigh and identify single nanoparticles and viruses. Given their small footprint, however, NEMS are plagued by low analyte detection rate since the active sensing cross-sections to capture analyte particles is very small. Here we report on the development of an on-chip focusing lens operating in air and integrated with the NEMS sensor. The integrated system increases the capture efficiency by orders of magnitude, and allows for operation under ambient conditions to measure the mass of nanoparticles and virions. With this system, mass spectrum of nanoparticle samples and mammalian viruses at biologically relevant concentrations can be characterized within less than 30 minutes

Protective effects of vitamin E against hypercholesterolemia-induced age-related diseases

Hypercholesterolemia is a major risk factor for age-related diseases such as atherosclerosis and Alzheimer’s disease (AD). Changes in human plasma cholesterol levels results from the interaction between multiple genetic and environmental factors. The accumulation of excess cholesterol in blood vessels leads to atherosclerosis. Many studies on this field show that differential expression of oxidative stress-related proteins, lipid metabolism-related enzymes, and receptors response to atherogenic diet. Additionally, excess brain cholesterol has been associated with increased formation and deposition of amyloid-β peptide from amyloid precursor protein which may contribute to the risk and pathogenesis of AD. To consider genetically, more than 50 genes have been reported to influence the risk of late-onset AD. Some of these genes might be also important in cholesterol metabolism and transport. Epidemiological studies have shown an association between high intake and high serum concentrations of antioxidant vitamins like vitamin E and lower rates of ischemic heart diseases. It has been known that vitamin E also inhibits smooth muscle cell proliferation by non-antioxidant mechanism. On the basis of the previous results, vitamin E has been accepted as an important protective factor against hypercholesterolemia-induced age-related diseases