nvasive bacterial pathogens, the Chlamydiae know us very, very well. The Chlamydiae learned to parasitize eukaryotic cells half a billion years ago by reprogramming cellular functions from within. In humans today, chlamydial infections are responsible for a range of ailments from sexually transmitted infections to atypical pneumonias to chronic severe disorders such as pelvic inflammatory disease and atherosclerosis. The Centers for Disease Control says that Chlamydia trachomatis is the most common sexually-transmitted infection in the US, with three million new cases a year.

Chlamydia gets around because it knows its hosts so well. It's an "obligate intracellular parasite" which means that it relies on its eukaryotic host for everything from reproduction to synthesizing ATP, all while living inside a membrane-bounded vacuole that provides a protected, fertile environment for the bacteria to grow and multiply. Because lipid acquisition from the host is necessary for chlamydial replication, these pathogens are essentially lipid parasites. So, to add insult to injury, Chlamydia apparently lives on our fat.

Chlamydia parasite lives off our fat...

It's a scene football fans will see over and over during the bowl and NFL playoff seasons: a player, often the quarterback, being slammed to the ground and hitting the back of his head on the landing.
Sure, it hurts, but what happens to the inside of the skull? Researchers and doctors long have relied upon crude approximations made from test dummy crashes or mathematical models that infer – rather loosely – what happens to the brain during traumatic brain injury or concussion.
But the truth is that the state of the art in understanding brain deformation after impact is rather crude and uncertain because such methods don't give any true picture of what happens. Now, mechanical engineers at Washington University in St. Louis and collaborators have devised a technique on humans that for the first time shows just what the brain does when the skull accelerates.
What they've done is use a technique originally developed to measure cardiac deformation to image deformation in human subjects during repeated mild head decelerations. Picture, if you will, a mangled quarterback's occipital bone banging the ground, then rebounding. The researchers have mimicked that very motion with humans on a far milder, gentler, smaller scale and captured the movement inside the brain by magnetic resonance imaging (MRI).

New technique puts brain-imaging research on its head

A standard Internet protocol that checks errors made during email transmissions has now inspired a revolutionary method to transform DNA microarray analysis, a common technology used to understand gene activation. The new method, which blends experiment and computation, strengthens DNA microarray analysis, according to its Carnegie Mellon University inventor, who is publishing his findings in the December issue of Nature Biotechnology with collaborators at the Hebrew University in Israel.
The innovative method combines a new experimental procedure and a new algorithm to identify gene activation captured by DNA microarray analysis with greater sensitivity and specificity. The work holds great promise for vastly improving research on health and disease, according to Ziv Bar-Joseph, assistant professor of computer science and biological sciences at Carnegie Mellon.

Carnegie Mellon U. transforms DNA microarrays with standard Internet communications tool

Most people can rather efficiently walk and chew gum at the same time, but when it comes to more complicated "multi-tasking" – like driving and talking on a cell phone – there is a price to pay.
And no one, it seems, is immune.
"There is a cost for switching from one task to another and that cost can be in response time or in accuracy," said
Mei-Ching Lien, an assistant professor of psychology at Oregon State University. "Even with a seemingly simple task, structural cognitive limitations can prevent you from efficiently switching to a new task."
Psychologists who study multi-tasking have argued for years about whether these "information bottlenecks" occur because people are inherently lazy, or because they have a fundamental inability to switch from one task to another. New studies by Lien and her colleagues at the NASA Ames Research Center in California suggest it is the latter.
Results of their study have been published in the Journal of Experimental Psychology.

Cell phones, driving don't mix

Picture a teaspoon of powdered sugar. As fine a substance as it is, there still are tremendous differences in the sizes of its individual particles. Some are so small, they move around randomly and are invisible to the naked eye.
Now, let's say you wanted to choose only particles of a certain size from those in the spoon. Traditional technology and scientific techniques can separate quantities of particles of different sizes down to a few microns, but beyond that, it's not currently possible to perform this operation at the submicron level. Being able to do so would allow for the production of certain types of drugs that are most effective when inhaled.
How small is a submicron? Consider that a micron is a mere 0.00004 of an inch. Yet unlocking the mystery of how to manipulate, measure and separate very tiny particles has tremendous applications for the pharmaceutical industry and could change how some medications are delivered and how effective they are.

Magnet lab researcher exploring science behind commercial applications of liquid helium

Howard Hughes Medical Institute researchers have discovered a vast network of neurons in the brain of mice that governs reproduction and controls the effects of reproductive status on other brain functions.
In their studies, the researchers found neural circuits that coordinate a complex interplay between neurons that control reproduction and brain areas that carry the neural signals triggered by odorant molecules and those triggered by pheromones, chemical signals produced by animals. The researchers characterize their findings as an initial step in understanding the far-reaching influence that odors and pheromones may have on reproduction and other behaviors.

The brain is broadly wired for reproduction

Until now, physicists who wanted to understand how electrons behaved at the nanoscale needed to choose between instruments which had good spatial resolution (down to tens of nanometers or below) or fast time resolution (down to picoseconds), but not both. But researchers at the Ecole Polytechnique F餩rale de Lausanne (EPFL) in Switzerland have developed a new machine able of tracking electrons at trillionths of a second. This system can work with any semiconductor and may lead to new discoveries in physics of nanoscale phenomena.
This system took four years of development to a team led by BenoDeveaud-Pl餲an of EPFL's Laboratory of Quantum Optoelectronics (LOEQ). Here is what the researchers did.

Inside a quantum dot ....

Laser light has been used to remotely control gene therapy in rats. This mechanism will help make gene therapy more effective by allowing the precise time and location at which new genes are activated to be controlled, meaning specific tissues can be targeted while healthy tissues are left alone.
Lasers have been used in the past to perforate cells for gene therapy in cultured cells. But the new research – activating marker genes in the eyes of rats – is more sophisticated and the first time lasers have been used for gene therapy in live animals.
Kazunori Kataoka, at the University of Tokyo, Japan, and colleagues developed a photosensitive molecular complex that could be activated in rats’ eyes by irradiating them with visible light from a low power laser.
The synthetic complex is designed to deliver foreign DNA by carrying

Laser activates gene therapy in rats’ eyes

Hwang Woo-Suk, South Korea’s cloning pioneer, has resigned from his official posts, taking responsibility for ethical violations by his team during landmark research to grow human embryonic stem cells from a cloned embryo.
Hwang said on Thursday that junior researchers in his team had donated their own eggs without his permission. The donation of eggs carries a small risk and ethical rules forbid junior members of teams doing so, to avoid the possibility of coercion. Hwang also said that other women were paid for eggs used in his breakthrough project, also without his knowledge.
He admitted that he had lied when ethical questions began to surface in 2004 about the origin of the supply of human eggs available to his researchers

Cloning pioneer admits ethical violations and quits....

A dense bed of light-sensitive bacteria has been developed as a unique kind of photographic film. Although it takes 4 hours to take a picture and only works in red light, it also delivers extremely high resolution.
The “living camera” uses light to switch on genes in a genetically modified bacterium that then cause an image-recording chemical to darken. The bacteria are tiny, allowing the sensor to deliver a resolution of 100 megapixels per square inch.

Living camera uses bacteria to capture image