Prenatal Arsenic; Electric Fish; Cholera
- Prenatal arsenic exposure can alter genes
- The children of mothers whose water supplies were contaminated with arsenic during their pregnancies harbored gene expression changes that may lead to cancer and other diseases later in life, MIT researchers reported in a new study. In addition to establishing the potential harmful effects of these prenatal exposures, the study also provides a possible method for screening populations to detect signs of arsenic contamination.
This is the first time evidence of such genome-wide changes resulting from prenatal exposure has ever been documented from any environmental contaminant. It suggests that even when water supplies are cleaned up and the children never experience any direct exposure to the pollutant, they may suffer lasting damage.
- Omnidirectional Electric Fish
- What could an African lion stalking a distant impala in the African savanna possibly have in common with an electric fish searching for nearby water fleas in the Amazon River? Both the lion and the rather less daunting 14-cm black ghost knifefish (Apteronotus albifrons) use sensory information to help them to locate and catch prey. But lions, which rely on their acute vision during the hunt, engage in passive sensing, whereas the knifefish actively senses by generating a weak electric field around its body. And while lions and most other predators both sense and move mainly in the forward direction, the knifefish can sense in all directions and swim rapidly backward and forward to intercept its prey.
PLoS Biology paper
- Princeton scientists break cholera’s lines of communication
- A team of Princeton scientists has discovered a key mechanism in how bacteria communicate with each other, a pivotal breakthrough that could lead to treatments for cholera and other bacterial diseases.
The mechanism is a chemical that cholera bacteria use for transmitting messages to each other, known as CAI-1, and has been isolated in the lab of molecular biologist Bonnie Bassler. Her team has shown that the chemical also can be used to disrupt the communication that exists among the bacteria, potentially halting the disease’s progress. The discovery could lead to an entirely new class of antibiotics.
“Disease-causing bacteria talk to each other with a chemical vocabulary, and now we can interfere with their talk to control infections,” said Doug Higgins, a graduate student in Bassler’s lab and first author of the research team’s paper on the findings. “This paper specifically concerns cholera, but it provides proof in principle that we can do it with any bacteria.”