Targeting cancer with magnetic microcarrier – Nanomedicine | As a rule chemotherapy is like using a blunderbuss against cancer. ‘Chemo’ is administered through the bloodstream, which of course goes everywhere in the body. While the anti-cancer chemistry can be targeted to a certain extent, it almost always has toxic side effects with other organs and systems. Consequently, one of the most important goals of cancer research has been improvement of targeting – getting just the right chemistry to just the right location (specific cells). There are many avenues of research, one of the most promising uses nanotechnology. Recently Sylvain Martel and colleagues at Polytechnique Montreal (Canada) used a specially rigged MRI system to guide a tiny sphere, dubbed a microcarrier, magnetized with nanoparticles. Inserted into the hepatic artery of a rabbit, the sphere was magnetically moved into position within a specific area of the liver where its contents (doxorubicin) were progressively released. This technique appears ready for preparation to be used in human trials.
[BioMaterials, Volume 32, Issue 13, May 2011, Pages 3481-3486, Co-encapsulation of magnetic nanoparticles and doxorubicin into biodegradable microcarriers for deep tissue targeting by vascular MRI navigation]
W.H.O. response to pandemic that wasn’t is criticized – Pandemics | The H1N1 “Swine Flu” pandemic of 2009 fizzled. Thank goodness. The World Health Organization (W.H.O.) received a lot of criticism for promoting a worldwide pandemic management and vaccination program, in large part because the H1N1 virus (a cross of pig, human and avian genetics) turned out to be no more virulent than ‘normal’ flu. Now a follow-up study of the H1N1 episode, at the behest of W.H.O., finds that the world was lucky: W.H.O. and its member countries, particularly those involved with the new International Health Regulations (IHR) were not and are not ready for a seriously dangerous pandemic. The report, which will be officially released later this year, largely clears W.H.O. for its timing in declaring an emergency and for charges of being influenced by large drug companies, but it finds fault with the uncertainty of W.H.O. categorization of the outbreak and with the ability of W.H.O. to manage the IHR agreements between countries. Consider the 2009 H1N1 outbreak a dry-run, a chance to critique and improve the world’s response capability. The next outbreak may not be so meek.
[New York Times, 10 March 2011, Response of W.H.O. to swine flu is criticized]
Title – Photonics | Perhaps you’ve heard that quantum computers are ‘just around the bend’ so to speak. It could be a long curve. Nevertheless, by the time quantum computers become real it would be a good idea to hook them to quantum networks. To that end researchers at Northwestern University (Illinois, USA) have demonstrated a network switching device (a switch changes the route of network information) that can handle quantum bits (particles of light involved in the quantum effect called entanglement) without losing the embedded information. In this case the quantum bit (qubit) is a photon, which is emitted by a device the researchers created called a Entangled Photon Source. Pairs of entangled photons (entangled meaning that both photons are linked by a quantum relationship) are transmitted via optic fiber through the new photonic switch – without losing their entanglement. This quantum communication is many times faster than existing digital systems and only needs quantum computers to become the high powered computing of the future – a few years down the line.
[Physical Review Letters, 1 February 2011, Ultrafast switching of photonic entanglement]
Synthetic biology: Replacement urinary tubes – Synthetic Biology | The first human replacement of damaged urinary tubes (urethra) with synthetically produced tissue may not seem like a glamorous piece of synthetic biology, and it isn’t – and that’s the point. Researchers are now developing ‘artificial’ tissue replacements for a number of organs, many of them sort of ‘routine’ but nonetheless vital for the person whose native equipment is defective. The researchers at Wake Forest Baptist Medical Center (USA) have progressed to human trials, in this case, replacing long segments of urinary tubes in five boys. Creating these tubes with tissue grafts has a high failure rate (around 50%). The synthetic tubes are grown from the patient’s own cells and do not provoke a tissue rejection. They are more easily controlled for size, shape and consistency, which should result in a much lower failure rate. Determining that rate will be part of the next phase of human testing.
Nanotiles make a programmable processor – Computer Power | Using nanotechnology components for computing is one of the most active of all research areas. Much of the activity concerns using nanotubes and other carbon-based nano-shapes for digital switches (for memory and logic components). In this case engineers and scientists at Harvard University and MITRE Corporation (USA) have created nanowire tiles that can be arranged in the world’s first programmable nanoprocessor. Charles Lieber and colleagues use carbon nanowires that are arranged by some breakthrough processing technology to form circuitry on a ‘tile’ (a substrate material). This is analogous to printing circuits on silicon chips of traditional computing, but here the tiles are at the nano scale. They are so tiny that the power consumption is negligible and each circuit can retain a charge (like computer memory), yet stacked together the tiles form complex circuits that can perform logic and arithmetic. This combination of non-volatile memory and programmable circuits – at the nanoscale – constitutes a new and potentially important approach to developing computers ‘from the bottom up.’ That is, instead of designing complete circuits and imprinting them on a semiconductor, the processors circuits are built piece by piece (tile by tile). The end product will be, in the not too distant future, computer processors no bigger than the head of a pin (on which the angels will dance).
[Nature, 9 February 2011, Programmable nanowire circuits for processors]