Mostrando entradas con la etiqueta biomedicine. Mostrar todas las entradas
Mostrando entradas con la etiqueta biomedicine. Mostrar todas las entradas

20/12/07

Gold nanoparticles, radiation combo may slow Alzheimer's

Chemists in Chile and spain have identified a new approach for the possible treatment of Alzheimer's disease that they say has the potential to destroy beta-amyloid fibrils and plaque -- hypothesized to contribute to the mental decline of Alzheimer's patients. The researchers say the new technique, which they call a type of "molecular surgery," could halt or slow the disease's progress without harming healthy brain cells. The research is scheduled for publication in the Jan. 11 issue of the American Chemical Society's Nano Letters.

Using test tube studies, the scientists attached gold nanoparticles to a group of beta amyloid fibrils, incubated the resulting mixture for several days and then exposed it to weak microwave fields for several hours. The energy levels of the fields were six times smaller than that of conventional cell phones and unlikely to harm healthy cells, the researchers say. The fibrils subsequently dissolved and remained dissolved for at least one week after being irradiated, indicating that the treatment was not only effective at breaking up the fibrils but also resulted in a lower tendency of the proteins to re-aggregate, according to the researchers.

The same approach also holds promise for treating other neurodegenerative diseases that involve protein aggregation, including Parkinson's and Huntington's, says study leader Marcelo J. Kogan, of the University of Chile in Santiago. He says that the approach is similar to that of another experimental technique that uses metallic nanoparticles to label and destroy cancer cells. Animal studies are planned, Kogan says.

There's currently no cure for Alzheimer's disease and no one is sure of its exact causes. The disease affects an estimated 4.5 million people in the United States, according to the National Institute on Aging. That figure is expected to rise dramatically as the population ages, experts predict.

9/7/07

Gold Nanoparticles and cancer



Lopez-Quintela and colleagues (J Invest Dermatol. 2007 Jul;127(7):1701-12) have recently reported that inorganic nanoparticles (smaller than 10 nm) may penetrate human skin and occasionally permeate the skin. Skin penetration through the stratum corneum lipidic matrix with nanoparticles could be a very powerful drug delivery strategy.






M.A. Lopez-Quintela is part of the scientific advisory board of Nanogap. He is leading the biomedical researchs of Nanogap, aided by Prof. Fernando Domínguez and Prof. Benito Regueiro.

29/5/07

Soft machines II



In this second part of the post we will see possible paralelisms between nanoechnology and nature in order to improve our engineering skills at the nanoscale

In nature, Surface forces + Brownian motion = self-assembly. Complex structures are made by self assembly. How can we copy that? We can do synthetic self assembly with block copolymers. It’s simple, cheap and available in. On the other hand using nucleic acids let to design structures from designed sequences but it is expensive and delicate.

Brownian motion + lack of stiffness = conformational translations. Motor proteines change shape in response to changes in the environment. We can copy that combining a responsive polymer with an oscillating chemical reaction: e.g. synthetic muscle (expanding and contracting in response of changes in pH)

What areas might bio-inspired nano trasnform? Energy, information and medicine seem possible candidates at the first sight. Humanity is existentially dependent on technology for its survival at current and projected populations, but the tech we have isn't sustainable in the energy, environment and medicine fields. Nanotechnology can help.

In the energy field there is the terawatt challenge: as the world continues growing, the demand of energy will be bigger. There's plenty of sunlight, we must develop Viable photovoltaics (need lower processing costs and large areas) and solar cells for electricity or hydrogen. Any options? Biokleptic approach (photosyntetic bacteria) or biomimetic approach (nanotitania).

The drug delivery is another important field where nanotechnology can mimic nature. We can develop semi-intelligent biomedical nanobots propelled by chemicals reactions using its own coating with self motile reactions.

So what is the future of nanotechnology? It seems that it won’t be shrinking mechanical engineering. Nanotechnology will be soft and bio based. It will be more like biology than engineering.

Once again we must be very cautious with the toxicity of this nanotechnology advances and we must engage with the public about nanotechnology before polarised positions appears.




Thanks to prof. Richard Jones from the Univ. of Sheffield


Recommended links: http://www.softmachines.org/; http://www.shef.ac.uk/physics/people/rjones/; http://nanobot.blogspot.com/; http://en.wikipedia.org/wiki/Nanorobotics