Most of us know how hard it is to resist the creamy sweetness of ice cream. But it might surprise you to learn that, over the past 15 years or so, some makers of ice cream and many other processed foods—from pasta to ground beef products—have changed their recipes to swap out some of the table sugar (sucrose) with a sweetening/texturizing ingredient called trehalose that depresses the freezing point of food. Both sucrose and trehalose are “disaccharides.” Though they have different chemical linkages, both get broken down into glucose in the body. Now, comes word that this switch may be an important piece of a major medical puzzle: why Clostridium difficile (C. diff) has emerged as a leading cause of hospital-acquired infections.
A new study in the journal Nature indicates that trehalose-laden food may have helped fuel the recent epidemic spread of C. diff., which is a microbe that can cause life-threatening gastrointestinal distress, especially in older patients getting antibiotics and antacid medicines [1, 2]. In laboratory experiments, an NIH-funded team found that the two strains of C. diff. most likely to make people sick possess an unusual ability to thrive on trehalose, even at very low levels. And that’s not all: a diet containing trehalose significantly increased the severity of symptoms in a mouse model of C. diff. infection.
The term “freeze-dried” may bring to mind those handy MREs (Meals Ready to Eat) consumed by legions of soldiers, astronauts, and outdoor adventurers. But if one young innovator has his way, a test that features freeze-dried biosensors may soon be a key ally in our nation’s ongoing campaign against the very serious threat of antibiotic-resistant bacterial infections.
Each year, antibiotic-resistant infections account for more than 23,000 deaths in the United States. To help tackle this challenge, Ahmad (Mo) Khalil, a researcher at Boston University, recently received an NIH Director’s New Innovator Award to develop a system that can more quickly determine whether a patient’s bacterial infection will respond best to antibiotic X or antibiotic Y—or, if the infection is actually viral rather than bacterial, no antibiotics are needed at all.
As a child, Patrick Hsu once settled a disagreement with his mother over antibacterial wipes by testing them in controlled experiments in the kitchen. When the family moved to Palo Alto, CA, instead of trying out for the football team or asking to borrow the family car like other high school kids might have done, Hsu went knocking on doors of scientists at Stanford University. He found his way into a neuroscience lab, where he gained experience with the fundamental tools of biology and a fascination for understanding how the brain works. But Hsu would soon become impatient with the tools that were available to ask some of the big questions he wanted to study.
As a Salk Helmsley Fellow and principal investigator at the Salk Institute for Biological Studies, La Jolla, CA, Hsu now works at the intersection of bioengineering, genomics, and neuroscience with a DNA editing tool called CRISPR/Cas9 that is revolutionizing the way scientists can ask and answer those big questions. (This blog has previously featured several examples of how this technology is revolutionizing biomedical research.) Hsu has received a 2015 NIH Director’s Early Independence award to adapt CRISPR/Cas9 technology so its use can be extended to that other critically important information-containing nucleic acid—RNA.Specifically, Hsu aims to develop ways to use this new tool to examine the role of a certain type of RNA in cancer drug resistance.
As long as she can remember, Ashley Matthew wanted to be a medical doctor. She took every opportunity to pursue her dream, including shadowing physicians to learn more about what a career in health care is really like. But, as Matthew explains in today’s LabTV video, she also became attracted to the idea of doing research because of her affinity for solving problems and “figuring things out.”
So, Matthew decided to give biomedical research a try, landing a spot in an undergraduate summer program sponsored by the University of Massachusetts. Ten weeks later, she was convinced that her future in medicine just had to include a research component. That’s why Matthew is now well on her way as an M.D./Ph.D. student at the University of Massachusetts Medical School, Worcester, where she works in the lab of Celia Schiffer.
It would be great if we could knock out cancer with a single punch. But the more we learn about cancer’s molecular complexities and the immune system’s response to tumors, the more it appears that we may need a precise combination of blows to defeat a patient’s cancer permanently, with no need for a later rematch. One cancer that provides us with a ringside seat on the powerful potential—and tough challenges—of targeted combination therapy is melanoma, especially the approximately 50% of advanced tumors with a specific “driver” mutation in the BRAF gene .
Drugs that target cells carrying BRAF mutations initially provided great hope for melanoma, with many reports of dramatic shrinkage of tumors in patients with advanced disease. But almost invariably, the disease recurred and was no longer responsive to those same drugs. A few years ago, researchers thought they’d come up with a solid combination to fight BRAF-mutant melanoma: a one-two punch that paired a BRAF-inhibiting drug with an agent that sensitized the immune system . However, when that combo was tested in humans, the clinical trial had to be stopped early because of serious liver toxicity . Now, in a mouse study published in Science Translational Medicine, NIH-funded researchers at the University of California, Los Angeles (UCLA) provide renewed hope for a safe, effective combination therapy for melanoma—with a strategy that adds a third drug to the mix .