Tag Archives: university research

Waste Treatment Plants Result in Super Bacteria

Multiple antibiotic-resistant bacteria has emerged as one of the top public health issues worldwide in the last few decades as the overuse of antibiotics and other factors have caused bacteria to become resistant to common drugs. Chuanwu Xi‘s group chose to study Acinetobacter because it is a growing cause of hospital-acquired infections and because of its ability to acquire antibiotic resistance.

Xi said the problem isn’t that treatment plants don’t do a good job of cleaning the water—it’s that they simply aren’t equipped to remove all antibiotics and other pharmaceuticals entering the treatment plants.

The treatment process is fertile ground for the creation of superbugs because it encourages bacteria to grow and break down the organic matter. However, the good bacteria grow and replicate along with the bad. In the confined space, bacteria share resistant genetic materials, and remaining antibiotics and other stressors may select multi-drug resistant bacteria.

While scientists learn more about so-called superbugs, patients can do their part by not insisting on antibiotics for ailments that antibiotics don’t treat, such as a common cold or the flu, Xi said. Also, instead of flushing unused drugs, they should be saved and disposed of at designated collection sites so they don’t enter the sewer system.

The next step, said Xi, is to see how far downstream the superbugs survive and try to understand the link between aquatic and human superbugs. This study did not look past 100 yards.

Xi’s colleagues include visiting scholar Yongli Zhang; Carl Marrs, associate professor of public health; and Carl Simon, professor of mathematics.

Xi and colleagues found that while the total number of bacteria left in the final discharge effluent declined dramatically after treatment, the remaining bacteria was significantly more likely to resist multiple antibiotics than bacteria in water samples upstream. Some strains resisted as many as seven of eight antibiotics tested. The bacteria in samples taken 100 yards downstream also were more likely to resist multiple drugs than bacteria upstream.

Full press release

Graphene: Engineered Carbon

A material for all seasons

Graphene, a form of the element carbon that is just a single atom thick, had been identified as a theoretical possibility as early as 1947.
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Its unique electrical characteristics could make graphene the successor to silicon in a whole new generation of microchips, surmounting basic physical constraints limiting the further development of ever-smaller, ever-faster silicon chips.

But that’s only one of the material’s potential applications. Because of its single-atom thickness, pure graphene is transparent, and can be used to make transparent electrodes for light-based applications such as light-emitting diodes (LEDs) or improved solar cells.
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Graphene could also substitute for copper to make the electrical connections between computer chips and other electronic devices, providing much lower resistance and thus generating less heat. And it also has potential uses in quantum-based electronic devices that could enable a new generation of computation and processing.

“The field is really in its infancy,” says Michael Strano, associate professor of chemical engineering who has been investigating the chemical properties of graphene. “I don’t think there’s any other material like this.”

The mobility of electrons in graphene — a measure of how easily electrons can flow within it — is by far the highest of any known material. So is its strength, which is, pound for pound, 200 times that of steel. Yet like its cousin diamond, it is a remarkably simple material, composed of nothing but carbon atoms arranged in a simple, regular pattern.

“It’s the most extreme material you can think of,” says Palacios. “For many years, people thought it was an impossible material that couldn’t exist in nature, but people have been studying it from a theoretical point of view for more than 60 years.”

Evolutionary Robotics

Evolutionary Robotics, chapter of Handbook of Robotics, is interesting and includes a good explanation of the difference between evolution and learning:

Evolution and learning (or phylogenetic and ontogenetic
adaptation) are two forms of biological adaptation that differ in space and time. Evolution is a process of selective reproduction and substitution based on the existence of a population of individuals displaying variability at the genetic level. Learning, instead, is a set of modifications taking place within each single individual during its own life time.

Evolution and learning operate on different time scales. Evolution is a form of adaptation capable of capturing relatively slow environmental changes that

might encompass several generations (e.g., the perceptual characteristics of food sources for a given species). Learning, instead, allows an individual to adapt to environmental modifications that are unpredictable at the generational level. Learning might include a variety of mechanisms that produce adaptive changes in an individual during its lifetime, such as physical development, neural maturation, variation of the connectivity between neurons, and synaptic plasticity. Finally, whereas evolution operates on the genotype, learning affects only the phenotype and phenotypic modifications cannot directly modify the genotype.
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Recent research showed that teams of evolved robots can: (a) develop robust and effective behavior, (b) display an ability to differentiate their behavior so
to better cooperate; (c) develop communication capabilities and a shared communication system.

Nanoparticles With Scorpion Venom Slow Cancer Spread

In a, chlorotoxin molecules, colored blue and green, attach themselves to a central nanoparticle. In b, each nanoprobe offers many chlorotoxin molecules that can simultaneously latch on to many MMP-2s, depicted here in yellow, which are thought to help tumor cells travel through the body. In c, over time nanoprobes draw more and more of the MMP-2 surface proteins into the cell, slowing the tumor’s spread. Image from the University of Washington.

University of Washington researchers found they could cut the spread of cancerous cells by 98 percent, compared to 45 percent for the scorpion venom alone, by combining nanoparticles with a scorpion venom compound already being investigated for treating brain cancer.

For more than a decade scientists have looked at using chlorotoxin, a small peptide isolated from scorpion venom, to target and treat cancer cells. Chlorotoxin binds to a surface protein overexpressed by many types of tumors, including brain cancer. Previous research by Miqin Zhang‘s group combined chlorotoxin with nanometer-scale particles of iron oxide, which fluoresce at that size, for both magnetic resonance and optical imaging.

Chlorotoxin also disrupts the spread of invasive tumors — specifically, it slows cell invasion, the ability of the cancerous cell to penetrate the protective matrix surrounding the cell and travel to a different area of the body to start a new cancer. The MMP-2 on the cell’s surface, which is the binding site for chlorotoxin, is hyperactive in highly invasive tumors such as brain cancer. Researchers believe MMP-2 helps the cancerous cell break through the protective matrix to invade new regions of the body. But when chlorotoxin binds to MMP-2, both get drawn into the cancerous cell.

Research showed that the cells containing nanoparticles plus chlorotoxin were unable to elongate, whereas cells containing only nanoparticles or only chlorotoxin could stretch out. This suggests that the nanoparticle-plus-chlorotoxin disabled the machinery on the cell’s surface that allows cells to change shape, yet another step required for a tumor cell to slip through the body.

So far most cancer research has combined nanoparticles either with chemotherapy that kills cancer cells, or therapy seeking to disrupt the genetic activity of a cancerous cell. This is the first time that nanoparticles have been combined with a therapy that physically stops cancer’s spread.

Full press release

Amazonian Ant Species is All Female, Reproduces By Cloning

Ants inhabit ‘world without sex’

The ants reproduce via cloning – the queen ants copy themselves to produce genetically identical daughters. This species – the first ever to be shown to reproduce entirely without sex – cultivates a garden of fungus, which also reproduces asexually.
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Dr Himler’s interest in Mycocepurus smithii was originally sparked not by their unusually biased sex ratio, but by their ability to cultivate crops. “Ants discovered farming long before we did – they have been cultivating fungus gardens for an estimated 80 million years.

“They collect plant material, insect faeces and even dead insects from the forest floor and feed it to their crops,” she said.

Bacteria Communicate Using a Chemical Language

Each person has about 1 trillion human cells and about 10 trillion bacterial cells. In the webcast Bonnie Bassler, Department of Molecular Biology at Princeton University, discusses the chemical language that lets bacteria coordinate defense and mount attacks (quorum sensing). The find has stunning implications for medicine, industry — and our understanding of ourselves.

Bacteria do all sorts of amazing things for us: educating your immune system to keep bad microbes out, they digest our food, they make our vitamins…

Why Toddlers Don’t Do What They’re Told

Toddlers listen, they just store the information for later use, a new study finds.

“I went into this study expecting a completely different set of findings,” said psychology professor Yuko Munakata at the University of Colorado at Boulder. “There is a lot of work in the field of cognitive development that focuses on how kids are basically little versions of adults trying to do the same things adults do, but they’re just not as good at it yet. What we show here is they are doing something completely different.”
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“If you just repeat something again and again that requires your young child to prepare for something in advance, that is not likely to be effective,” Munakata said. “What would be more effective would be to somehow try to trigger this reactive function. So don’t do something that requires them to plan ahead in their mind, but rather try to highlight the conflict that they are going to face. Perhaps you could say something like ‘I know you don’t want to take your coat now, but when you’re standing in the yard shivering later, remember that you can get your coat from your bedroom.”

Using Virus to Build Batteries

MIT researchers have shown they can genetically engineer viruses to build both the positively and negatively charged ends of a lithium-ion battery. We have posted about similar things previously, for example: Virus-Assembled Batteries – Using Viruses to Construct Electrodes and Biological Molecular Motors. New virus-built battery could power cars, electronic devices

Gerbrand Ceder of materials science and Associate Professor Michael Strano of chemical engineering, genetically engineered viruses that first coat themselves with iron phosphate, then grab hold of carbon nanotubes to create a network of highly conductive material.

Because the viruses recognize and bind specifically to certain materials (carbon nanotubes in this case), each iron phosphate nanowire can be electrically “wired” to conducting carbon nanotube networks. Electrons can travel along the carbon nanotube networks, percolating throughout the electrodes to the iron phosphate and transferring energy in a very short time. The viruses are a common bacteriophage, which infect bacteria but are harmless to humans.

The team found that incorporating carbon nanotubes increases the cathode’s conductivity without adding too much weight to the battery. In lab tests, batteries with the new cathode material could be charged and discharged at least 100 times without losing any capacitance. That is fewer charge cycles than currently available lithium-ion batteries, but “we expect them to be able to go much longer,” Belcher said.

This is another great example of university research attempting to find potentially valuable solutions to societies needs. See other posts on using virus for productive purposes.

E.O. Wilson: Lord of the Ants

This is a great webcast on E.O Wilson‘s career studying ants and animal behavior from NOVA.

Not only is the scientific knowledge very interesting it again shows that challenging conventional wisdom, while part of the scientific method, does not mean it is an easy process for those pioneers. From his web site:

In 1971 Wilson published his second major synthesis, The Insect Societies, which formulated the existing knowledge of the behavior of ants, social bees, social wasps, and termites, on a foundation of population biology. In it he introduced the concept of a new discipline of sociobiology, the systematic study of the biological basis of social behavior in all kinds of organisms. In 1975 he published Sociobiology: The New Synthesis, which extended the subject to vertebrates and united it more closely to evolutionary biology. The foundational discoveries of sociobiology are generally recognized to be the analysis of animal communication and division of labor, in which Wilson played a principal role, and the genetic theory of the origin of social behavior, which he helped to promote and apply in his 1971 and 1975 syntheses. Sociobiology: The New Synthesis was later ranked in a poll of the officers and fellows of the international Animal Behaviour Society as the most important book on animal behavior of all time, and is regarded today as the founding text of sociobiology and its offshoot, evolutionary psychology.

Related: Journey to the Ants: A Story of Scientific Exploration
by Bert HÃ¶lldobler and Edward O. Wilson – Huge Ant Nest – Symbiotic relationship between ants and bacteria – Royal Ant Genes – posts on ants – Encyclopedia of Life

Image of the Common Cold Virus

image created by Dr. Jean-Yves Sgro, Institute for Molecular Virology, University of Wisconsin-Madison, from published X-ray data. larger image

Sequences capture the code of the common cold

Conducted by teams at the University of Maryland School of Medicine, UW-Madison and the J. Craig Venter Institute, the work to sequence and analyze the cold virus genomes lays a foundation for understanding the virus, its evolution and three-dimensional structure and, most importantly, for exposing vulnerabilities that could lead to the first effective cold remedies.

“We’ve had bits and pieces of these things for a long time,” says Ann Palmenberg, of UW-Madison’s Institute for Molecular Virology and the lead author of the new study. “Now, we have the full genome sequences and we can put them into evolutionary perspective.”

As its name implies, the common cold is an inescapable, highly contagious pathogen. Humans are constantly exposed to cold viruses, and each year adults may endure two to four infections, while schoolchildren can catch as many as 10 colds.

“We know a lot about the common cold virus,” Palmenberg explains, “but we didn’t know how their genomes encoded all that information. Now we do, and all kinds of new things are falling out.”
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The newly sequenced viruses also show, says Palmenberg, why it is unlikely we will ever have an effective, all-purpose cold vaccine: The existing reservoir of viruses worldwide is huge and, according to the new study, they have a tendency to swap genetic sequences when cells are infected by more than one virus, a phenomenon that can lead to new virus strains and clinical manifestations.
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The ability of different cold virus strains to swap genes and make entirely new strains was thought to be impossible, notes Claire M. Fraser-Liggett, a co-author of the new study and director of the Institute for Genome Sciences and professor of medicine and microbiology at the University of Maryland School of Medicine. “There is the possibility that this could lead to the emergence of a new rhinovirus strain with fairly dramatic properties,” says Fraser-Liggett.