SRI team finds chemical that turns anthrax lethal
Scientists from The Scripps Research Institute have discovered the key chemical that signals the anthrax bacterium to become lethal. Bicarbonate, a chemical found in all body fluids and organs and that plays a major role in maintaining pH balance in cells, provides the signal for Bacillus anthracis to unleash life-threatening factors. Scientists found that without the presence of the bicarbonate transporter in the bloodstream the bacteria do not become virulent.
Because other pathogenic bacteria have similar bicarbonate transport pathways, the finding is expected to open up new avenues for developing treatments for bacterial infections. The study appears in the journal “PLoS Pathogens.”
Cancer-meat linkUCSD School of Medicine researchers have shown how consuming red meat and milk products could increase the risk of cancerous tumors. The findings suggest that inflammation, resulting from a molecule introduced by eating these foods, promotes tumor growth.
In mouse studies, researchers examined a sugar molecule - N-glycolylneuraminic acid (Neu5Gc) - that can be incorporated into tissues as a result of eating red meat. The presence of Neu5Gc produced an immune response that led to chronic inflammation that stimulated tumors to grow faster. The findings appear in the “Proceedings of the National Academy of Sciences.”
On network efficiencyIf we were to route a letter to an unknown person using only friends or acquaintances who we thought might know the intended recipient, it would take five or six intermediaries before the letter reached its intended destination (the so-called six degrees of separation). The underlying success of this phenomenon is known as “small-world paradigm,” and it recently inspired the study of the Internet as a global complex network.
By constructing a mathematical model of the physical and logical elements underlying complex networks, researchers discovered that many shared a similar characteristic - their global topology (or shape) maximizes communication efficiency.
The result, published in “Nature Physics” may explain the “small-world phenomenon” as it relates to both man-made and natural networks. The new insight may also be relevant to removing mounting bottlenecks within the Internet that threaten the smooth passage of digital information around the globe.
The work was carried out through the Cooperative Association for Internet Data Analysis (CAIDA), based at the San Diego Supercomputer Center.