In a few years’ time, instead of fiddling with needle and thread, surgeons may simply use glue to connect implants to living tissue. They took their idea from mussels, which can stick to any surface, be it porous rock or the smooth hull of a ship.
It sounds like a venturous plan: Implants such as artificial heart valves and vessels are to be welded to the body’s own tissue using a special glue, completely obviating the need for bothersome sutures, ScienceDaily said.
The bond will be rapidly hardened by UV light, so that only 30 seconds later, the foreign object is firmly implanted in the patient’s body.
Dr. Klaus Rischka, a chemist at the Fraunhofer Institute for Manufacturing Engineering and Applied Materials Research IFAM in Bremen, is confident that this scenario will soon become reality.
In the course of this award-winning project, the Fraunhofer researcher and his partners at Frankfurt University Hospital, the Center of Biotechnical Engineering BitZ at Darmstadt University of Technology, the State Materials Testing Institute MPA and the implant manufacturer Straumann in Freiburg will initially demonstrate the glue’s suitability on the basis of a dental implant made of titanium.
It is current practice to anchor tooth implants in the jaw bone without an adhesive. This often leaves gaps between the gums and the metal, allowing bacteria to enter and cause infections. A glue that firmly connects the gums to the implant would serve as an effective barrier against aggressive germs.
Conventional products are not suited to such a purpose, however, as they would sooner or later dissolve in the moist environment inside the mouth.
Mussels have provided the Fraunhofer experts with a solution: Over the course of evolution, these mollusks have developed a special glue that not only works under water, but is also a particularly firm and lasting bonding agent. The strength of the bond is due to a particular protein.
Chemists at IFAM are able to synthetically reproduce the key elements of the substance, and have already used them in a joint project with the European Space Agency ESA to develop an adhesive intended for everyday repairs in manned spaceflight.
The use of this substance in medical applications requires an additional ingredient: a growth protein, which can likewise be synthetically produced using the classic technique of solid-phase peptide synthesis.
Its purpose is to stimulate cell growth so that the body’s own tissue--in this case the gums--bonds as closely as possible with the implant. A third component, in the form of a classic polymer, is then added as a carrier substance.

Scrambled-up polymers can kill bacteria, and may offer hope in beating problems of antibiotic drug resistance, suggests a new study.
According to NewScientist.com, researchers at the University of Wisconsin, in Madison, US, had been working on making molecules that mimic the short proteins known as “host-defense peptides“.
They are produced as part of the innate immune response by all kinds of organisms--from plants to humans--to kill bacteria, and work, most researchers believe, by sticking onto bacteria’s membranes and opening holes in them.
To mimic these natural defenses, the researchers, led by Samuel Gellman and Shannon Stahl were building polymers by stringing together certain sub-units, called beta-lactams, in a particular order.
As a control for their experiments, they also assembled scrambled polymers with the sub-units in random order.
But to their surprise, the random polymers were better at killing bacteria, Gellman says. And compared with both the ordered polymers and the natural host-defense peptides, the random polymers killed many fewer red blood cells--a crude measure of their potential toxicity to humans.
Relatively low doses of the random polymers were able to kill drug-resistant bacteria, such as Staphylococcus aureus, which is resistant to the powerful antibiotic vancomycin.
The random polymers were effective against more bacteria, and less toxic to red blood cells, than three widely tested natural host-defense peptides, the study showed. “Our study is the first to show you can get polymers that match the selectivity of natural host-defense peptides,“ Gellman says.
The polymers seem to be attracted to bacteria’s negatively charged membranes, where the polymers reshape themselves and punch holes in the membrane. Animal cells, on the other hand, are generally neutrally charged, so the polymers are much less attracted to them.
“I’m really excited about this work,“ Gellman says, because it could provide a cheap way of producing a new class of antibiotics.
And the polymers should likewise remain effective for a long time, Gellman argues, since bacteria have a hard time evolving resistance to natural host-defense peptides.
This is because the peptides attack a fundamental part of the cell, the membrane, using a basic physical interaction rather than targeting a specific part of the cellular machinery inside, as man-made antibiotics typically do.
“It seems when they add randomness, they get away from the toxicity,“ says Robert Hancock of the University of British Columbia in Vancouver, Canada.

Until recently, a student solving a calculus problem, a physicist modeling a galaxy or a mathematician studying a complex equation had to use powerful computer programs that cost hundreds or thousands of dollars.
But an open-source tool based at the University of Washington won first prize in the scientific software division of Les Trophees du Libre, an international competition for free software, ScienceDaily reported.
The tool, called Sage, faced initial skepticism from the mathematics and education communities.
“I’ve had a surprisingly large number of people tell me that something like Sage couldn’t be done--that it just wasn’t possible,“ said William Stein, associate professor of mathematics and lead developer of the tool. “I’m hearing that less now.“
Open-source software, which distributes programs and all their underlying code for free, is increasingly used in everyday applications. Firefox, Linux and Open Office are well-known examples.
But until recently, nobody had done the same for the everyday tools used in mathematics. Over the past three years, more than a hundred mathematicians from around the world have worked with Stein to build a user-friendly tool that combines powerful number-crunching with new features, such as collaborative online worksheets.
Sage can take the place of commercial software commonly used in mathematics education, in large government laboratories and in math-intensive research. The program can do anything from mapping a 12-dimensional object to calculating rainfall patterns under global warming.
The idea began in 2005, when Stein was an assistant professor at Harvard University.
“For about 10 years I had been really unhappy with the state of mathematical software,“ Stein said. The big commercial programs--Matlab, Maple, Mathematica and Magma--charge license fees. The Mathematica Web page, for example, charges $2,495 for a regular license.
For another program, a collaborator in Colombia was quoted about $550, a special “Third World“ discount price, to buy a license to use a particular tool, Stein said.
The frustrations weren’t only financial. Commercial programs don’t always reveal how the calculations are performed.
This means that other mathematicians can’t scrutinize the code to see how a computer-based calculation arrived at a result.
“Not being able to check the code of a computer-based calculation is like not publishing proofs for a mathematical theorem,“ Stein said. “It’s ludicrous.“
So Stein began a year and a half of frenzied work in which he created the Sage prototype, combining decades’ worth of more specialized free mathematical software and filling in the gaps.

Some synthetic chemicals in household products can cause health problems by interfering with normal hormone action.

A new UC Davis study shows that a common antibacterial chemical added to bath soaps can alter hormonal activity in rats and in human cells in the laboratory--and does so by a previously unreported mechanism.
The findings come as an increasing number of studies--of both lab animals and humans--are revealing that some synthetic chemicals in household products can cause health problems by interfering with normal hormone action, Eurekalert reported.
Called endocrine disruptors, or endocrine disrupting substances (EDS), such chemicals have been linked in animal studies to a variety of problems, including cancer, reproductive failure and developmental anomalies.
This is the first endocrine study to investigate the hormone effects of the antibacterial compound triclocarban (also known as TCC or 3,4,4’-trichlorocarbanilide), which is widely used in household and personal care products including bar soaps, body washes, cleansing lotions, wipes and detergents.
Triclocarban-containing products have been marketed broadly in the United States and Europe for more than 45 years; an estimated 1 million pounds
of triclocarban are imported annually for the US market.
The researchers found two key effects: In human cells in the laboratory, triclocarban increased gene expression that is normally regulated by testosterone. And when male rats were fed triclocarban, testosterone-dependent organs such as the prostate gland grew abnormally large.
Also, the authors said their discovery that triclocarban increased hormone effects was new. All previous studies of endocrine disruptors had found that they generally act by blocking or decreasing hormone effects.
“This finding may eventually lead to an explanation for some rises in some previously described reproductive problems that have been difficult to understand,“ said one author, Bill Lasley, a UC Davis expert on reproductive toxicology and professor emeritus of veterinary medicine. More analyses of antibacterials and endocrine effects are planned, he said.
Consumers should not take this study as guidance on whether to use triclocarban-containing products, Lasley said. “Our mothers taught us to wash our hands well before the advent of antimicrobial soaps, and that practice alone prevents the spread of disease.“

Researchers cannot be certain if the increased mental impairment results specifically from higher sugar intake.

Excess drinking of sugary beverages like soda may increase the risk of Alzheimer’s disease, suggests new research in mice.
Although the exact mechanisms aren’t known, obesity and diabetes are both associated with higher incidences of Alzheimer’s.
Ling Li and her colleagues tested whether high sugar consumption in an otherwise normal diet would affect Alzheimer’s progression, Newswise.com said.
They used a genetic mouse model that develops Alzheimer’s-like symptoms in adulthood, and over a 25 week period supplemented the regular, balanced diet of half the animals with 10 percent sugar water. Afterwards, they compared the metabolism, memory skills (by means of various mazes) and brain composition of the regular and sugar-fed mice.
The sugar-fed mice gained about 17 percent more weight than controls, had higher cholesterol levels, and developed insulin resistance. These mice also had worse learning and memory retention and their brains contained over twice as many amyloid plaque deposits, an anatomical hallmark of Alzheimer’s.
Although the researchers cannot be certain if the increased mental impairment resulted specifically from the higher sugar intake or higher calories in general, these results to highlight the potential risk of sugary beverages.
They note that the human equivalent of the mouse diet would be roughly 5 cans of soda per day, although since mice have a higher metabolism, it may actually take less sugar intake in humans.

Many industrial processes involve reactions in places that are difficult to see directly. A novel tabletop touch screen allows hidden sequences of events to be observed in progress. It can be operated intuitively using a combination of fingers and recognizes swiping movements.
A crowd of people is gathered around a large table with an illuminated surface, on which images of a journey through pipes and machines in a factory are being displayed. Users can select individual components by touching the corresponding image with a finger, Physorg.com reported.
The objects can be rotated and observed by swiping a finger over them--and the same method can be used to watch a process in slow motion. By drawing apart their two index fingers on the table surface, users can enlarge the image and zoom in on a detail, such as a bay wheel scooping up hundreds of thousands of plastic granules.
The Multi-Touch Table provides a tangible virtual replication of processes that normally take place hidden inside networks of pipes: How does the process work? What are its advantages?
The large, industrial-scale display table was developed by researchers at the Fraunhofer Institute for Computer Graphics Research IGD in Darmstadt. “The table is already being used by the Coperion Group of companies,“ relates IGD project manager Michael Zollner.
“It allows customers to observe the entire process chain of plastics manufacturing and processing. They can watch in real time as the granulate flows through the pipes and regulate the speed by swiping a finger over the image.“
The researchers worked with colleagues at the Steinbeis Institute Design and Systems on the development of this application.
So how does the touch screen work? Infrared LEDs emit light into the Plexiglas surface of the display at a horizontal angle. This light is internally totally reflected within the acrylic sheet, which allows none of the light to escape.
A finger placed on the surface changes its reflective properties, enabling light to emerge. This light is captured by an infrared camera installed beneath the table. Although the system is based on well-known principles, various challenges still had to be overcome.
“The surface of acrylic sheets is too smooth to resolve finger movements. Our solution was to apply a special coating,“ says Zollner.

Some water striders can propel their bodies across the water surface at nearly 3.5 feet, or 100 times their body length, per second.

Walking on water may seem like a miracle to humans. But it is a humdrum achievement for the little water strider, which is able to bounce up and down on water too.
Scientists have already solved the mystery of how their six slender, stilt-like legs evenly distribute their scant body weight over a relatively large area so that the skin formed by the surface tension of the water supports them, so four millimeter across dimples form under each foot as they skim about, Telegraph.co.uk said.
But scientists remained puzzled by how they could jump up and down upon the surface of water.
Now a team in South Korea is about to report that it has at last explained the water strider’s baffling ability to leap onto water without sinking, in a forthcoming issue of the journal Langmuir, an achievement that could help further develop robots that can move about on lakes and reservoirs to monitor water quality, spy or explore.
Ho-Young Kim and Duck-Gyu Lee of Seoul National University note that scientists already have discovered the water-repellent, hairy structure of the water strider’s legs and how they enable the creatures to scoot along ponds and placid lakes.
They solved the mystery of how the insects jump onto or bounce off liquid surfaces by dropping a highly water-repellent sphere onto the surface of water at different speeds, carefully tracking its motion with high-speed cameras.
Footage revealed that the ball must be traveling within a narrow range of velocities in order to bounce off the water’s surface. The sphere may sink if it goes too fast and won’t bounce back if it is too slow.
This explains why water striders have extremely water repellent--superhydrophobic--legs, and how they touch down at just the right speed not to sink, said Dr Kim.
“Application of our study can be extended to developing semi-aquatic robots that mimic such insects having the surprising mobility on water.“
One team led by Metin Sitti at Carnegie Mellon University, Pittsburgh, has already built a lightweight spider microrobot able to walk on water.
The real thing is extraordinarily mobile. Some water striders can propel their bodies across the water surface at nearly 3.5 feet, or 100 times their body length, per second.
A six-foot-tall human swimming at a comparable speed would achieve around 400 mph.
The reason that the insects can skim around on water is because water molecules at the surface are strongly attracted to each other and those beneath, unlike the air above.
The result is surface tension, a skin-like effect that these insects exploit.
The strider’s legs can support 15 times the insect’s weight without it sinking, according to calculations.