Molecular imaging for cancer cells
One of the biggest promises of nanomedicine is that doctors will be able to deliver needed medications directly to a site within your body without negatively affecting other tissues. That’s still a moving target, though.
One of the most challenging obstacles is the density and opaqueness of human tissue such as blood vessel walls and organs. A recent study reported in ACS nano (American Chemical Society Nano) has revealed a way to more accurately track where nanoparticles go once inside the body by allowing visibility a little deeper into living tissue. A gel, injected into tissues removed from mice, linked all the molecules of the tissue together except for lipids – the substances responsible for making tissue opaque. Lipids washed easily away and “left the tissues clear but otherwise intact.”
Lest you picture a big chunk of clear material, the actual depth to which researchers could image nanoparticles was only 1 millimeter, but that’s 25 times deeper than with existing methods. The hope is that in addition to helping track nanoparticles, this approach will assist researchers with tissue engineering, implant and biosensor applications.
Slowly, we peel away one tiny layer at a time from the mysteries of nature.
English: A schematic showing the (laboratory) production of nitric oxide. The setup was made based on an image of the 1949 Popular Mechanics article by Kenneth M. Swezey (titled: The gas that makes you laugh). Images from http://commons.wikimedia.org/wiki/User:Rocket000/SVGs/Chemistry were used to make this image. (Photo credit: Wikipedia)
The substance nitric oxide (NO), one of my favorite topics, is now known to be break-downable into components, one of which has one less electron. It’s known as NO(-) or HNO or nitroxyl, and researchers are finding some exciting new applications for it.
One novel use for nitroxyl is as part of a nanoparticle coating for implanted medical devices that otherwise might trigger dangerous blood clots. The coating is made up of sheets of graphene integrated with two components—haemin and glucose oxidase. “Both work synergistically to catalyze the production of nitroxyl, which can be used inside the blood like nitric oxide, although it contains one less electron. Nitroxyl has been reported as being analogous to nitric oxide in its clot-preventing capability.”
The other use for nitroxyl (HNO) involves its use in treating heart failure. Researchers normally write in very reserved terms about their discoveries, but the author of the passage below seems pretty excited about the implications of the research. Basically it’s saying that HNO donors can do things that regular NO donors cannot do and may be dramatically more useful in treating cardiovascular disease.
Thus, unlike NO*, HNO can target cardiac sarcoplasmic ryanodine receptors to increase myocardial contractility, can interact directly with thiols and is resistant to both scavenging by superoxide (*O2-) and tolerance development. HNO donors are protective in the setting of heart failure in which NO donors have minimal impact.
It’s cool to see this showing three of my favorite topics coming together: nitric oxide, nanotechnology and heart failure. But then, when all is said and done someday, everything in bioscience will undoubtedly coalesce in one way or another.
English: An experimental setup used to measure the fraction of exhaled nitric oxide (FeNO) in human breath samples. The subject blows into the tube (1) after a mouthpiece (2) has been connected to it. The wires on the side measure parameters like breath velocity, while the exhaled gas is taken to a FeNO analyzer (3). (Photo credit: Wikipedia)
The first item is about nitric oxide (NO) used in testing, and the rest are all about using nanoparticles for delivering things into the human body, including NO. It’s astounding that scientists have found nanotechnology so helpful in these kinds of applications. I just hope more research is done on how safe it is to inject nanomaterials into our bodies or make us breathe them in. Their size is so similar to the deadly asbestos fibers that are currently costing billions in lawsuits by workers whose companies didn’t protect them from breathing and ingesting them.
Gotta make sure the cure doesn’t damage the patient in different ways than the condition it’s meant to help.
- Mayo Clinic officially recognizes the exhaled-nitric-oxide test to confirm asthma diagnoses and to determine how well medications are working – http://www.mayoclinic.org/tests-procedures/nitric-oxide-test/basics/definition/prc-20012958
- Japanese researchers have found a way to use nano-sized particles to deliver nitric oxide to cells as needed – http://www.azonano.com/news.aspx?newsID=28613
- Government wants scientists to adapt nano-delivery systems to protect soldiers in the field from bio and chemical weapons – http://www.abqjournal.com/328885/news/dod-wants-protocell-to-protect-soldiers-2.html
- Nanoparticles can carry RNA gene-silencing snippet to treat breast cancer – http://www.azonano.com/news.aspx?newsID=29083
- Inhaled nanoparticles to carry antimicrobial meds to treat pneumonia caused by drug-resistant bacteria – http://www.nanowerk.com/nanotechnology_news/newsid=33688.php
Blood clot diagram (Thrombus) (Photo credit: Wikipedia)
Blood clots can wreck quality of life and even kill by causing a stroke or a heart attack. But up ’til now doctors have been unable to predict when a clot might develop in a particular patient. Now nanotechnology is making possible a way to read signals in your urine that your body may be getting ready to produce one of these little clots with such destructive potential.
Just as seismologists are developing new ways to be able to predict when a volcano will erupt, researchers have developed a urine test that uses nanoparticles to detect thrombin, a major element of blood clotting. The test was made by converting a process that’s currently in use to detect colorectal cancer and has been successfully tested in mice that are high-risk for blood clots.
Good news is that the iron oxide particles used in the test have already been approved for use in humans, so the time to clinical trials shouldn’t be too prolonged. The test will be used to help people in emergency rooms who have symptoms that resemble those caused by a blood clot and also to monitor others at high-risk, such as those who fly a lot or who must spend a lot of time in bed after surgery.
I have a relative who suffered a stroke at a young age, so I know how terrifying it can be – and how it can degrade a person’s quality of life. The goal of the new test is to make it as easy as, “Pee on this stick and call me in the morning.” Imagine the sadness, fear and suffering that could potentially be averted.
I’ve been worrying about potential danger from these guys ever since I first heard about them. Now comes some research indicating strongly that nanoparticles/nanofibers could be deadly to humans who are exposed to them. This particular research shows that it may be the length of the fibers that’s critical to whether they might eventually induce disease.
Some scientists set up the experiment with five types of silver nanofibers of various lengths and exposed mice to them. The mice developed inflammation in the pleura (the lining of the lungs) when exposed to fibers of a certain length—4 µm to be precise (that’s 4 millionths of a micron). We are talking tiny.
Asbestos fibres - a single fibre is believed to cause mesothelioma (Photo credit: Wikipedia)
Since the pleura is exactly the same part of the body that is attacked when asbestos is breathed or ingested, researchers concluded their research could be relevant for colleagues investigating malignant pleural mesothelioma (MPM), a deadly and aggressive type of lung cancer. Mesothelioma, as yet incurable, is the subject of lawsuits across the US and around the world because so many corporations either negligently or deliberately concealed from workers the dangers of inhaling or ingesting asbestos.
Asbestos was and is (in third world countries where it is still being widely used without regard for its danger to humans) a highly profitable substance. Its fire-retardant and heat-resistant properties, as well as its ability to be flexible and to strengthen other substances have made it much sought-after for hundreds of years. Profits grew even as those who worked with it were being sickened because of inadequate protections. And the long latency period before asbestos diseases manifest has helped camouflage the disregard for human safety—people may develop mesothelioma cancer as late as 10, 20, 30 or even 50 years after being exposed to asbestos. Who was going to connect a lung disease in a 60-something-year-old with what he did for a living 30 years ago?
This new research is the first solid evidence I’ve seen that nanofibers may hold the same type of danger to human health and life as asbestos. And heaven knows, nanotechnology is looking to be even more profitable than asbestos. The permutations of products made better, stronger, more flexible—almost more anything you want—with nanotechnology seem almost limitless. As may also be the greed of those who stand to make enormous financial gains from its use.
Let’s hope all the profits and material gains do not come at the price of ever more human suffering and lost lives.