Ultrasound Patch Heals Venous Ulcers
Battery-operated ultrasound patch delivers therapeutic ultrasound to heal venous ulcers.
Photo: Drexel University
In a small clinical study, researchers administered a new method for treating chronic wounds using a novel ultrasound applicator that can be worn like a Band-Aid. The applicator delivers low-frequency, low-intensity ultrasound directly to wounds and was found to significantly accelerate healing in five patients with venous ulcers. Venous ulcers are caused when valves in the veins malfunction, causing blood to pool in the leg instead of returning to the heart. This pooling, called venous stasis, can cause proteins and cells in the vein to leak into surrounding tissue, leading to inflammation and formation of an ulcer.
The technology was developed by researchers at Drexel University with funding from the National Institute of Biomedical Imaging and Bioengineering.
Venous ulcers account for 80 percent of all chronic wounds found on lower extremities and affect approximately 500,000 U.S. patients annually, a number that’s expected to increase as obesity rates climb. It’s estimated that treatment for venous ulcers costs the U.S. health care system more than $1 billion per year.
Standard treatment for venous ulcers involves controlling swelling, taking care of the wound by keeping it moist, preventing infection and compression therapy—a technique in which patients wear elastic socks that squeeze the leg to prevent blood from flowing backwards. Despite these measures, wounds often take months and occasionally years to heal.
“Right now, we rely mostly on passive treatments,” said Dr. Michael Weingarten of Drexel, a researcher in the study. “With the exception of expensive skin grafting surgeries, there are very few technologies that actively stimulate healing of these ulcers.”
In an upcoming article in the Journal of the Acoustical Society of America, the Drexel researchers report that patients who received low-frequency, low-intensity ultrasound treatment during their weekly check-up (in addition to standard compression therapy) showed a net reduction in wound size after just 4 weeks.
Removing a Protein Enhances Defense Against Bacteria in CGD Mice
Deletion of a protein in white blood cells improves their ability to fight the bacteria staphylococcus aureus and possibly other infections in mice with chronic granulomatous disease (CGD), according to an NIDDK study. CGD, a genetic disorder also found in people, is marked by recurrent, life-threatening infections. The study’s findings appear online in the Journal of Clinical Investigation.
A team of NIDDK researchers compared three groups: CGD-afflicted mice with the protein Olfm4, CGD-afflicted mice in which the protein had been deleted and healthy mice in which the protein had been deleted. Olfm4, also known as olfactomedin 4, is sometimes helpful in limiting tissue damage but can also hinder white blood cells’ ability to kill bacteria.
The researchers found that the white blood cells in mice without the protein could better withstand staphylococcus aureus infection, a major threat to patients with CGD.
“Although treatment for CGD has greatly improved over the past several years, the disease remains challenging,” said Dr. Wenli Liu, staff scientist and lead author. “Our research suggests a novel strategy that might pave the way toward developing new treatments to fight against common and often deadly infections.”
Therapy for Severe Vasculitis Shows Long-Term Effectiveness
Administering the drug rituximab once weekly for 1 month provides the same benefits as 18 months of daily immunosuppressive therapy in people with severe forms of vasculitis, or inflammation of the blood vessels, a study has found.
Researchers from the Immune Tolerance Network (ITN), an international clinical trials group funded by the National Institute of Allergy and Infectious Diseases, found that rituximab is as effective as the standard therapy at inducing and maintaining disease remission. The findings appeared Aug. 1 in the New England Journal of Medicine.
In addition to these results, the online version of the study is the first to contain direct links to TrialShare External Web Site Policy, a new data analysis and sharing portal developed and managed by the ITN. The site provides access to the study’s raw data and statistical analyses, allowing researchers to re-analyze the data and develop new hypotheses. Currently, TrialShare houses data from eight ITN clinical studies.