An end to needle phobia: Device could make painless injections possible

"As many as 1 in 10 people experience needle phobia, which may have negative consequences, such as decreasing the rate of vaccinations and blood donation," said William McKay, M.D., lead author of the study. Credit: © uwimages / Fotolia

Imagine no tears during infant vaccines and no fear of the needle for those old enough to know what's coming. Such painless injections could be possible with a device that applies pressure and vibration while the needle is inserted in the skin, according to a study presented at the ANESTHESIOLOGY™ 2014 annual meeting.

"As many as 1 in 10 people experience needle phobia, which may have negative consequences, such as decreasing the rate of vaccinations and blood donation," said William McKay, M.D., lead author of the study and a professor of anesthesiology in perioperative medicine and pain management at the University of Saskatchewan, Saskatoon, Canada. 

"Our early research suggests that using a device that applies pressure and vibration before the needle stick could help significantly decrease painful sensations by closing the 'gate' that sends pain signals to the brain."

Researchers studied the use of pressure, vibration, and cooling or warming in 21 adults poked in the shoulder by a plastic needle that doesn't break the skin but produces needle-like pain. They tested different levels of pressure, vibration and temperature to determine the amount that provided the most benefit. The perception of pain was significantly decreased when a specific amount of pressure and vibration was applied to the site for 20 seconds prior to using the plastic needle. The addition of heat added a small benefit, but it wasn't significant. The study should be repeated in children, who may experience pain differently, said Dr. McKay. The addition of heat or cold might be more beneficial, he said.

While commercial devices that include some of these features are available, they could be improved by incorporating the additional features tested in this and other studies, he said. They could be used to prevent pain prior to providing intravenous (I.V.) treatment, the drawing or donating of blood, or administering vaccinations.

The concept likely works by distraction as well as employing the gate-control theory of pain, in which these sensations (pressure, vibration and potentially temperature) close the gate that allows the brain to register pain.

Source: American Society of Anesthesiologists (ASA)

Microbiologists discover how gut bacterial resources are hijacked to promote intestinal, foodborne illnesses

Dr. Vanessa Sperandio. Credit: Image courtesy of UT Southwestern Medical Center

UT Southwestern Medical Center microbiologists have identified key bacteria in the gut whose resources are hijacked to spread harmful foodborne E. coli infections and other intestinal illnesses.

Though many E. coli bacteria are harmless and critical to gut health, some E. coli species are harmful and can be spread through contaminated food and water, causing diarrhea and other intestinal illnesses. Among them is enterohemorrhagic E. coli or EHEC, one of the most common foodborne pathogens linked with outbreaks featured in the news, including the multistate outbreaks tied to raw sprouts and ground beef in 2014.

The UT Southwestern team discovered that EHEC uses a common gut bacterium called Bacteroides thetaiotaomicron to worsen EHEC infection. B. thetaiotaomicron is a predominant species in the gut's microbiota, which consists of tens of trillions of microorganisms used to digest food, produce vitamins, and provide a barrier against harmful microorganisms.

"EHEC has learned to how to steal scarce resources that are made by other species in the microbiota for its own survival in the gut," said lead author Dr. Meredith Curtis, Postdoctoral Researcher at UT Southwestern.

The research team found that B. thetaiotaomicron causes changes in the environment that promote EHEC infection, in part by enhancing EHEC colonization, according to the paper, appearing in the journal Cell Host Microbe.

"We usually think of our microbiota as a resistance barrier for pathogen colonization, but some crafty pathogens have learned how to capitalize on this role," said Dr. Vanessa Sperandio, Professor of Microbiology and Biochemistry at UT Southwestern and senior author.

EHEC senses changes in sugar concentrations brought about by B. thetaiotaomicron and uses this information to turn on virulence genes that help the infection colonize the gut, thwart recognition and killing by the host immune system, and obtain enough nutrients to survive. The group observed a similar pattern when mice were infected with their equivalent of EHEC, the gut bacterium Citrobacter rodentium. Mice whose gut microbiota consisted solely of B. thetaiotaomicron were more susceptible to infection than those that had no gut microbiota. Once again, the research group saw that B. thetaiotaomicron caused changes in the environment that promoted C. rodentium infection.

"This study opens up the door to understand how different microbiota composition among hosts may impact the course and outcome of an infection," said Dr. Sperandio, whose lab studies how bacteria recognize the host and how this recognition might be exploited to interfere with bacterial infections. "We are testing the idea that differential gastrointestinal microbiota compositions play an important role in determining why, in an EHEC outbreak, some people only have mild diarrhea, others have bloody diarrhea and some progress to hemolytic uremic syndrome, even though all are infected with the same strain of the pathogen."

The Centers for Diseases Control and Prevention (CDC) estimates that each year roughly 1 in 6 Americans (or 48 million people) gets food poisoning; 128,000 are hospitalized;, and 3,000 die of their food-borne disease. EHEC, which also caused a widespread outbreak in Europe in 2011, can lead to bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome, which in turn can lead to kidney disease and failure. EHEC is among the top five pathogens contributing to domestically acquired foodborne illnesses resulting in hospitalization, according to the CDC. Outbreaks in 2014 were reported in California, Idaho, Massachusetts, Michigan, Missouri, Ohio, Montana, Utah, and Washington.

Source: UT Southwestern Medical Center