Parasite Affects Instinctive Fear

A common single-cell pathogen (Toxoplasma gondii) removes the instinctive fear of predators (cats) in rodents, possibly permanently modifying a specific brain function as an evolutionary adaptation for the parasite, which can only reproduce sexually within the cat gut.

Bacteria in Storm Clouds

Researchers have found bacteria on hailstones that ordinarily live on plants and in the soil, suggesting these bacteria present a new transient microbial ecosystem in storm clouds where they reproduce and affect cloud chemistry and may influence weather patterns as nucleation points for precipitation.

Diagnosing Parkinson's Audibly

A researcher at MIT has developed audio-recognition software trained to identify 10 dysphonias in human voices and diagnose the early onset of Parkinson's disease with 99% accuracy, taking advantage of the disease's early effect on controlling the vocal chords and soft palate.

Common Cause of ALS

Researchers have discovered a common cause of all forms of amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease: a malfunctioning protein recycling system in the neurons of the brain and spinal cord that provides a common target for drug therapy.

Rinderpest Virus Eliminated

For only the second time in history, humanity has succeeded in eliminating a disease virus completely -- namely, the rinderpest (German for "cattle plague") virus that once killed cattle by the millions and lead to famine among human populations for thousands of years, with the last known case reported in Kenya in 2001.

Antibiotic Insect Brains

Researchers have identified nine different molecules present in the brain and nervous systems of cockroaches and locusts that have strong antibiotic properties, including substances that are up to 90% effective at killing Staphylococcus aureus (MRSA) and Escherichia coli without harming human cells.

Dolphins Control Their Diabetes

Researchers have found that bottlenose dolphins have developed a type of insulin resistance, equivalent to type 2 diabetes in humans, yet have a physiological mechanism to activate this trait only when conditions require it -- essentially turning their "diabetes" on and off at will.

Chemically Changing Bacteria

Restricting inorganic phosphates from the diet of the common hospital infections P. aeruginosa and E. coli change the microorganism from harmful pathogen to benign or even defensive colonizers.

Engineered Viruses Fight Drug-Resistant Bacteria

Researchers at the Massachusetts Institute of Technology and Boston University have engineered a virus that attacks bacterial defense systems, strengthening the effects of antibiotics.

Antibiotic-resistant bacteria are an increasing health risk, and the development of new antibiotics is slow and expensive. But researchers have developed another solution by engineering existing bacteriophages (viruses that infect bacteria) to attack specific bacterial targets. The engineered viruses attack the SOS system, the DNA repair system that activates when bacteria are exposed to antibiotics that damage DNA. Used with conventional antibiotics, the new viruses undermine the natural defenses of bacteria and prevent them from repairing the damage and surviving to become resistant.

The engineered bacteriophages were tested with three families of antibiotics (quinolones, beta-lactams and aminoglyclosides) in mice and had promising results with all three. The possibility exists of developing an entire "library" of customized bacteriophages to be used in conjunction with existing antibiotics.

These results were published in the March 2nd issue of the Proceedings of the National Academy of Sciences.

Source: ScienceDaily

Global Survey of Oral Microbes Completed

Researchers at the National Institutes of Health have completed the first in-depth study of the global diversity of the human oral microbiome.

More than 600 different species of bacteria were found to live in human saliva, with the composition of each person's oral microbiome as unique as a fingerprint. Samples were studied from six geographic areas around the globe and the microbiome of each was found not to vary significantly, regardless of location, ethnicity or diet. This research is part of a recent initiative to study the microbiomes of several areas of the human body, with previous work focusing on the intestines and skin.

The human body harbors ten times more foreign microorganisms than body cells. As the mouth is the ideal gateway for foreign entry into the body, an easily obtained saliva sample is valuable for the study of the health effects disease, diet or cultural factors. It could also lead to the analysis of human migrations and populations around the world.

These results were published in the February 27th edition of Genome Research.

Source: ScienceDaily

White-Nose Syndrome Killing Bats in Northeastern U.S.

Biologists at the U.S. Fish and Wildlife Service have identified a mysterious white fungus that is responsible for devastating bat populations in the northeastern United States.

First identified two years ago, scientists have isolated a white fungus that grows on the muzzle (hence the name "white-nose syndrome") and body of bats and thrives in the extreme cold and dry conditions of winter caves. The exact mechanism by which this fungus kills the bats is not yet understood, but the condition appears to have an 80% to 100% mortality rate. Some hibernacula (bat colonies) have lost as many as 90% of their numbers.

White-nose syndrome was first found in caves in upstate New York, Vermont, western Massachusetts and Connecticut but has spread this year to caves as far as New Jersey and Pennsylvania. Little brown bats are the most affected species, although the disease has also affected northern long-eared and small-footed bats, eastern pipistrelle bats as well as the Indiana bat, currently listed as an endangered species. Because female bats birth only one pup per year, this syndrome may have serious consequences to their overall population.

Bats play a crucial role in many ecosystems by keeping the insect population in check as well as providing pollination for some plants. The fungus is not believed to pose a health risk for humans but there is a fear that this syndrome could spread unchecked and spur an ecological crisis as local bat colonies disappear.

This news was released recently by the Northeast Region of the U.S. Fish and Wildlife Service.

Source: Yahoo!

Single Gene Allows Bacteria to Migrate between Hosts

Scientists at the University of Wisconsin-Madison have discovered that a single gene allows a bacteria to migrate to new host species.

Both marine species bobtail squid and pinecone fish use bacteria-based bioluminescence as part of their camouflage and hunting techniques. The same species of bacteria, Vibrio fischeri, was found in both marine animals with one exception: the difference of a single additional gene in the variety present in the squid. This extra gene serves as a regulatory agent that allows the bacteria to colonize the new host species.

Virtually every animal known (including humans) has a variety of microorganisms specifically associated with that species, and microbial life crossing species to infect a new host is very rare. Scientists previously believed this rarity was due to bacteria requiring a wide set of new genes to successfully infect a different animal.

This research reveals that a single regulatory gene is all that is necessary to migrate to a new host species. Knowledge of this process may assist in the development of new drugs or therapies as a single gene is easier to target for the prevention or treatment of infection.

These results were published in the February 1st issue of Nature.

Source: ScienceDaily

Blue Light Destroys MRSA

Researchers at the New York Institute of Technology have discovered that a certain wavelength of blue light destroys the virulent antibiotic-resistant strain of the Staph bacteria known as MRSA.

In a process known as photo-irradiation, two common strains of methicillin-resistant Staphylococcus aureus (MRSA) were exposed to various doses of 470 nm blue light, a wavelength that does not emit ultraviolet radiation. The team found that the greater the dose of light used, the more microorganisms were killed. Up to 90.4% in colonies of the MRSA strains US-300 and IS-853 were destroyed using this method.

The precise method by which this process works is not fully understood but it is believed the DNA of the bacteria absorbs the energy of these specific wavelengths, causing irreparable damage and eventual cell death. Researchers have long known the bactericidal effects of 400-nm light and ultraviolet radiation, with research as far back as 1930. Blue light of 415 nm has been used to treat acne cases by destroying Propionibacterium acne, and the infectious Pseudomonas aeruginosa is killed by light with a wavelength of 405 nm.

MRSA poses an increasing health threat, as approximately 40% to 50% of all staphylococcal strains have developed resistance to modern antibiotics such as methicillin. Less than 5% of staphylococcal strains are currently susceptible to penicillin treatments. The use of blue light in the laboratory suggests it may be effective for the treatment of cutaneous and subcutaneous infections without promoting further resistance to antibiotics.

These results are scheduled to appear in the April issue of Photomedicine and Laser Surgery.

Source: ScienceDaily; Photo: Wikipedia

New Family of Antibacterial Agents Discovered

Scientists at the University of Kiel have identified a new family of antimicrobial proteins that could be used to fight bacteria growing resistant to current antibacterial treatments.

Called macins, this new family includes the protein identified as hydramacin, a derivative obtained from the tiny freshwater animals Hydra. Other members of this family include two antimicrobial compounds previously discovered in leeches, with all these proteins similar to a superfamily known to exist in scorpion venom.

Laboratory tests have shown hydramacin to be extremely effective at killing both Gram-positive and Gram-negative bacteria, and sharing virtually no similarity with other commonly used antibacterial proteins. Hydramacin also proved effective at killing drug-resistant strains such as Klebsiella oxytoca, an infectious agent commonly found in hospitals.

These results were published in a recent issue of the Journal of Biological Chemistry.

Photo: ScienceDaily