(Press-News.org) (PHILADELPHIA) - Despite extensive procedures to sterilize small and large bone fragments used in joint replacement or reconstructive surgeries, the rate of infection remains around 5 percent and can reach 11 percent or even higher in bone repairs for gunshot wounds or reconstruction after tumor removal. Infection after surgery is a serious complication that can require further surgery and can be life threatening. A new study demonstrates for the first time that an antimicrobial dye activated by light avidly adheres to bone to prevent bacteria from growing on bone fragments used in reconstructive surgery, and remove any bacteria that has already attached, thereby sterilizing the bone for surgery. The study was published online April 17 ahead of print in the journal of Clinical Orthopaedics and Related Research.
"We used a class of chemicals called porphyrins that are tolerated very well by the body in the dark and appear to have excellent antimicrobial properties in the presence of light," says Noreen Hickok, Ph.D., Associate Professor of Orthopedic Surgery at Thomas Jefferson University. "These properties allow sterilization during surgical procedures, which occur in bright light."
Surgeons often use bone chips or bone powder as a sort of putty during bone reconstruction to help areas of bone re-grow. Also, larger pieces of bone are used all over the world when a tumor or accident requires replacement of a large segment of bone. These bone materials can come either from the patient or a donor and are typically sterilized with a series of methods including various detergents and high pressure steam sterilization. But bacteria can still creep in once the material is handled again. "Bacteria really love to hide and grow in the nooks and crannies of porous bone and bone fragments - it's one of the most perfect surfaces for bacterial growth," says Dr. Hickok.
The researchers took these bone chips and treated them with a green dye called TAPP (which stands for 5,10,15,20-tetrakis-(4-aminophenyl)-porphyrin). They showed that in the dark, TAPP is stable. But when the lights go on, TAPP becomes active, producing chemicals called reactive oxygen species, or ROS, that rapidly kill the bacteria. Dr. Hickok and colleagues first treated the bone putty with TAPP and then exposed those fragments to bacteria. As long as the lights were on, bacteria was unable to attach and grow on the surface of the bone.
The researchers then showed that TAPP not only prevents bacterial growth, but can also break up bacterial slime, or biofilms, already growing on the bone fragments. They demonstrated this by first allowing bacteria to colonize the bone and then treating with TAPP. Finally, Dr. Hickok and colleagues showed that the dye binds tightly to the bone, without any trace of leaching out into surrounding fluid, suggesting that it could be safe and non-toxic to normal tissue once implanted.
In theory, says Dr. Hickok, the TAPP dye could be added to the currently used protocols for sterilizing the bone prior to use in surgery. "Sterilization could then occur in two steps--one which was achieved with a targeted illumination, and the other would be the continuation of the activation in the bright lights of the surgical suite so that the sterilizing effects of the ROS release could continue well into surgery and implantation," says Dr. Hickok. "We need to continue testing in conditions that more closely resemble the surgical suite, but we think that this method could offer a more effective method to help improve patient outcomes by reducing infection rates."
INFORMATION:
This research was supported by a National Institute of Arthritis and Musculoskeletal and Skin Diseases training grant T32-AR-052273, a National Institutes of Health grant R01 HD061053, research funding from the National Institutes of Health, Synergy Biomedical, Collegeville, PA, USA, and Zimmer, Warsaw, IN, USA. The Musculoskeletal Transplant Foundation provided human bone allograft.
For more information, contact Edyta Zielinska, 215-955-5291, edyta.zielinska@jefferson.edu.
About Jefferson -- Health is all we do.
Our newly formed organization, Jefferson, encompasses Jefferson Health and Thomas Jefferson University, representing our clinical and academic entities. Together, the people of Jefferson, 19,000 strong, provide the highest-quality, compassionate clinical care for patients, educate the health professionals of tomorrow, and discover new treatments and therapies that will define the future of health care.
Jefferson Health comprises five hospitals, 13 outpatient and urgent care centers, as well as physician practices and everywhere we deliver care throughout the city and suburbs across Philadelphia, Montgomery and Bucks Counties in Pa., and Camden County in New Jersey. Together, these facilities serve more than 78,000 inpatients, 238,000 emergency patients and 1.7 million outpatient visits annually. Thomas Jefferson University Hospital is the largest freestanding academic medical center in Philadelphia. Abington Hospital is the largest community teaching hospital in Montgomery or Bucks counties. Other hospitals include Jefferson Hospital for Neuroscience in Center City Philadelphia; Methodist Hospital in South Philadelphia; and Abington-Lansdale Hospital in Hatfield Township.
Thomas Jefferson University enrolls more than 3,900 future physicians, scientists, nurses and healthcare professionals in the Sidney Kimmel Medical College (SKMC); Jefferson Schools of Health Professions, Nursing, Pharmacy, Population Health; and the Graduate School of Biomedical Sciences, and is home of the National Cancer Institute (NCI)-designated Sidney Kimmel Cancer Center
For more information and a complete listing of Jefferson services and locations, visit http://www.jefferson.edu.
SALT LAKE CITY, Utah, May 7, 2015 - Myriad Genetics, Inc. (NASDAQ: MYGN) today announced it will present three studies that demonstrate the value of the Prolaris test for physicians and their patients at the 2015 American Urological Association (AUA) Annual Meeting being held May 15 to 19 in New Orleans, La.
Key presentations will showcase a new "active surveillance threshold" for men with localized prostate cancer based on the Prolaris test score, and the final results from PROCEDE 1000, which is the largest prospective clinical utility study to measure the impact of ...
COLUMBUS, Ohio - When highly educated, dual-career couples have their first child, both spouses think the baby increases their workloads by equal amounts - but a new study suggests that's not true.
When asked directly, both men and women thought their own daily workloads had increased by more than four hours after their child was born.
Detailed time diaries that the new mothers and fathers kept told a different story. Both spouses overestimated their increased workload - but by widely varying amounts. Compared to the parents' estimated four hours of extra work each ...
SAN FRANCISCO - Only half of women with cystic fibrosis (CF) report using contraception and frequently apt to become pregnant unintentionally, according to a new study from researchers at the Perelman School of Medicine at the University of Pennsylvania. The results of the study were presented earlier this week at the 2015 American Congress of Obstetricians and Gynecologists Annual Clinical and Scientific Meeting in San Francisco. As recently as the 1960s, children with cystic fibrosis - an inherited disease that causes thick, sticky mucus to form in the lungs, pancreas, ...
Quantity of water on Earth not unique
Water likely reached Earth via comets and asteroids crashing into Earth's surface
Evidence found in the atmosphere of white dwarf star
Asteroid found to contain 30-35% Earth's water content
Research led by the University of Warwick and published by Royal Astronomical Society
Water delivery via asteroids or comets is likely taking place in many other planetary systems, just as it happened on Earth, new research strongly suggests.
Published by the Royal Astronomical Society and led by the University of Warwick, the research ...
PHILADELPHIA, PA, May 7, 2015 -- For residents of areas with limited access to healthy foods, also known as food deserts, multiple barriers exist that amplify the health risks of living in those areas. Likewise, risks for poor diet and being overweight or obese are also increased. Researchers from the RAND Corporation, however, found that use of a list when shopping among low-income, predominantly African-American participants living in a food desert was associated with a better-quality diet and lower weight. Their results are published in the current issue of the Journal ...
PHILADELPHIA, PA, May 7, 2015 - Vitamin D is essential for the maintenance of bone health and may be implicated in other chronic diseases, as well as immunity, but adults in Canada are consistently deficient in dietary vitamin D, by nearly 400 international units per day (IU/d) on average. Coupled with low vitamin D synthesis from the sun during fall and winter at Canadian latitudes, tracking intake of vitamin D is vital for those lacking the nutrient. In an article in the Journal of Nutrition Education and Behavior, a group from the University of Guelph examined the validity ...
Climate change denial in public discourse may encourage climate scientists to over-emphasise scientific uncertainty and is also affecting how they themselves speak - and perhaps even think - about their own research, a new study from the University of Bristol, UK argues.
Professor Stephan Lewandowsky, from Bristol's School of Experimental Psychology and the Cabot Institute, and colleagues from Harvard University and three institutions in Australia show how the language used by people who oppose the scientific consensus on climate change has seeped into scientists' discussion ...
Philadelphia - Some at-risk patients opted out of comprehensive cancer gene screening when presented with the opportunity to be tested for the presence of genes linked to various cancers, according to a recent study led by researchers at the Perelman School of Medicine at the University of Pennsylvania and the Basser Center for BRCA in Penn's Abramson Cancer Center. Concern for uncertainty and potential distress were cited among the most common reasons to refuse testing. The results, published in Genetics in Medicine, were released just weeks ahead of an announcement of ...
Following lifestyle guidelines about diet, physical activity and maintaining a healthy weight is associated with an improved likelihood of survival when diagnosed with bowel cancer. This is based on the findings of a large study of over 500,000 published in the open access journal BMC Medicine.
Bowel cancer, also called colorectal cancer, is the second most common cancer in men and the third most common cancer in women worldwide, with 55% cases occurring in developed regions such as North America and Western Europe. Survival rates of bowel cancer have wide variations ...
Fans of The Lord of the Rings may disagree, but when it comes to exquisite excavation, the dwarves of Moria have nothing on the mighty fire ants of Georgia Tech. But Dan Goldman and Michael Goodisman aren't fascinated by the aesthetics of fire ant architecture alone. 'I have an interest in animals interacting with complex materials', explains Goldman, who has studied creatures such as sidewinder snakes and sandfish lizards moving through and across sand. With the ants on their doorstep, Goldman and Goodisman were intrigued to learn more about how the insects work together ...
