Newswise — Doctors, pilots, air traffic controllers and bus drivers have at least one thing in common — if they're exhausted at work, they could be putting lives at risk. But the development of a new urine test, reported in the ACS journal Analytical Chemistry, could help monitor just how weary they are. The results could potentially reduce fatigue-related mistakes by allowing workers to recognize when they should take a break. The effects of fatigue have long been recognized and studied as a problem in the transportation and healthcare industries. In the early 2000s, studies published in scientific journals reported that fatigue-related mistakes were linked to thousands of vehicular crashes every year, and were a major concern in patient safety. Weariness can cause anyone on or off the job to lose motivation and focus, and become drowsy. Although very common, these symptoms come with biochemical changes that are not well understood. Zhenling Chen, Xianfa Xu and colleagues set out to determine whether a urine test could detect these changes. The researchers analyzed urine samples from dozens of air traffic controllers working in civil aviation before and after an 8-hour shift on the job. Out of the thousands of metabolites detected, the study identified three that could serve as indicators of fatigue. Further work is needed to validate what they found, the researchers say, but their initial results represent a new way to investigate and monitor fatigue — and help prevent worn-out workers from making potentially dangerous errors. The authors acknowledge funding from the National Natural Science Foundation of China and the Civil Aviation Administration of China.
Newswise — MANHATTAN, KANSAS — Kansas State University researchers have discovered the secret ingredient to improving kitchen food safety: include hand-washing reminders and meat thermometer instructions in published recipes. Edgar Chambers IV, co-director of the university's Sensory Analysis Center, and collaborative food scientists have found that only 25 percent of people use a meat thermometer when they are cooking at home. But when a recipe includes a reminder, 85 percent of people will use a thermometer. The researchers saw similar results for hand-washing: Only 40 to 50 percent of people wash their hands when cooking, but 70 to 80 percent of people will wash their hands when a recipe reminds them. "This is such an easy thing to do: Just add the information to the recipe and people follow it," said Edgar Chambers, who is also a university distinguished professor of food, nutrition, dietetics and health. "It's a simple way to reduce foodborne illness and we can actually reduce health care costs by simply adding information to recipes. It's a great finding and a great piece of information for the promotion of food safety information." Chambers and his research team – including researchers at Tennessee State University and RTI International in North Carolina — have published the research in the Journal of Food Protection. They presented the results to the U.S. Department of Agriculture, which intends to start including these food safety instructions in recipes that it develops, Chambers said. The four-year collaborative project is supported by a $2.5 million USDA grant. The researchers have spent three years studying consumer shopping and cooking behaviors. Now the researchers are spending the fourth and final year working with the Partnership for Food Safety Education in Washington, D.C., to develop a nationwide food safety campaign. The researchers want to educate consumers, manufacturers, grocers, journalists, magazines and publishers on the importance of including food safety instructions in published recipes. "We want to provide research-based information for consumers," Chambers said. "The goal is to promote safe behaviors so that people actually begin to do them every day in the kitchen and as part of their shopping behavior." The project focused on several areas of food safety with poultry and eggs, including using meat thermometers, washing hands frequently and storing meat in plastic bags provided by the grocery stores. The researchers observed 75 people cook two dishes — a Parmesan chicken breast and a turkey patty with mushroom sauce — following recipes that did not have food safety instructions. Another group of 75 participants cooked the same dishes following recipes that did include food safety instructions. The dishes required the participants to handle raw meat, eggs and fresh produce while scientists observed how often the participants washed their hands or used a meat thermometer. By comparing the two groups, the researchers found that 60 percent more people used a meat thermometer and 20 to 30 percent more people washed their hands when the recipes included reminders about the two food safety practices. "This is such a wonderful outcome," Chambers said. "It's such an easy thing to do and such an easy way to help people remember to be safe. It doesn't cost anything — just a little extra paper and a little extra time to wash your hands and use that thermometer." The researchers also are studying kitchen lighting, which also can affect food safety. Many people are switching to LED lights and energy-efficient lights for kitchens, which is great news for consumers, but bad news for food safety, Chambers said. The energy-efficient lights make meat and poultry appear as if they are more done than they actually are. "We have shown through research that changing to more modern lighting in kitchens makes people believe their meat patties are done sooner than they would be under old lighting, which is wrong," Chambers said. "That is not good news for consumers unless they are using a meat thermometer." The researchers recently published the lighting-related research in the Journal of Sensory Studies. The Sensory Analysis Center is an internationally recognized research institute that conducts consulting, education and consumer sensory research on a variety of products and topics. SEE ORIGINAL STUDY
Newswise — The study is the first to look closely at the effects of the Sleep Healthy Using the Internet (SHUTi) program on people with health conditions that could be affecting their sleep. SHUTi aims to help people overcome their sleep problems by retraining them in healthy sleep behaviors. It is built on cognitive behavioral therapy, a widely used treatment for insomnia. Of the 303 people enrolled in the study, about half had either a medical or psychiatric condition. Ultimately, approximately 70 percent of the SHUTi users had significant improvements, and more than half (56.6 percent) were in the "no insomnia" range one year after using SHUTi. In general, SHUTi proved significantly more effective than online sleep education information – the type of tips that might be found online – provided to a control group of study participants. "We really tried to have as robust a study design as we possibly could to see if [SHUTi] would stand up over time," said University of Virginia School of Medicine Professor Lee Ritterband, PhD, one of the program's creators. "We found that those who got the SHUTi intervention did much better…and the main symptoms of insomnia were significantly improved and stayed improved over time." Could Help 'Unimaginable Numbers' Based on the study findings, the researchers have concluded that online programs without in-person human involvement can meaningfully improve sleep. The Internet, they say, "provides a less-expensive, scalable treatment option that could reach previously unimaginable numbers of people." Overall, the study found that the benefits of SHUTi were similar to those found in trials of cognitive behavioral therapy delivered by healthcare providers. The measure of effectiveness was based on experiences self-reported by study participants rather than a measurement of time spent sleeping.
Newswise — Boston, Mass. — A new study led by researchers at Massachusetts Eye and Ear found that vestibular thresholds begin to double every 10 years above the age of 40, representing a decline in our ability to receive sensory information about motion, balance and spatial orientation. The report was published online ahead of print in Frontiers in Neurology. “In our study, vestibular decline was clearly evident above the age of 40,” said senior author Daniel M. Merfeld, Ph.D. (at right in photo), Director of the Jenks Vestibular Physiology at Mass. Eye and Ear and a Professor of Otolaryngology at Harvard Medical School. “Increased thresholds correlate strongly with poorer balance test results, and we know from previous studies that those who have poorer balance have much higher odds of falling.” More than half of the population will see a doctor at some point in their lives with symptoms related to the vestibular system (e.g., dizziness, vertigo, imbalance and blurred vision). The vestibular system, made up of tiny canals in the inner ear, is responsible for receiving information about motion, balance and spatial orientation. With the goal of determining whether sex or age affected the function of the vestibular system, the researchers administered balance and motion tests to 105 healthy people ranging from 18 to 80 years old and measured their vestibular thresholds (“threshold” refers to the smallest possible motion administered that the subject is able to perceive correctly). While they found no difference between the thresholds of male and female subjects, they found that the thresholds increased above the age of 40 for all motions studied. The researchers also found that these increasing thresholds strongly correlated with failure to complete a standardized test for balance. This correlation shows that fall risk is substantially impacted by vestibular function. Using data from previous studies, the researchers suggest that vestibular dysfunction could be responsible for as many as 152,000 American deaths each year. This estimate would place vestibular dysfunction third in the United States behind heart disease and cancer as a leading cause of death among Americans. The correlation between vestibular thresholds and balance also suggests that there may be better ways to screen vestibular function and ways to develop therapies that may improve their thresholds. “We’ve known for a long while that patients with vestibular disorders have disturbed balance,” said Dr. Merfeld. “If worse vestibular function leads to falls, perhaps we can develop balance aids or physical therapy exercises to improve balance or vestibular function and prevent those falls.” Authors on the Frontiers in Neurology report include Dr. Merfeld, Maria Carolina Bermudez Rey, Tania Leeder and Yong Bian of the Jenks Vestibular Physiology Laboratory at Massachusetts Eye and Ear/Harvard Medical School; Torin K. Clark, of the Jenks Vestibular Physiology Laboratory at Mass. Eye and Ear/Harvard Medical School and the University of Colorado at Boulder; Wei Wong, of Brigham and Women’s Hospital/Harvard Medical School. Research supported by NIH/NIDCD R01-DC01458 and R01-DC014924. About Massachusetts Eye and EarMass. Eye and Ear clinicians and scientists are driven by a mission to find cures for blindness, deafness and diseases of the head and neck. Now united with Schepens Eye Research Institute, Mass. Eye and Ear is the world's largest vision and hearing research center, developing new treatments and cures through discovery and innovation. Mass. Eye and Ear is a Harvard Medical School teaching hospital and trains future medical leaders in ophthalmology and otolaryngology, through residency as well as clinical and research fellowships. Internationally acclaimed since its founding in 1824, Mass. Eye and Ear employs full-time, board-certified physicians who offer high-quality and affordable specialty care that ranges from the routine to the very complex. In the 2016–2017 “Best Hospitals Survey,” U.S. News & World Report ranked Mass. Eye and Ear #1 in the nation for ear, nose and throat care and #1 in the Northeast for eye care. For more information about life-changing care and research, or to learn how you can help, please visit MassEyeAndEar.org.
Newswise — To "turn off" particular regions of genes or protect them from damage, DNA strands can wrap around small proteins, called histones, keeping out all but the most specialized molecular machinery. Now, new research shows how an enzyme called KDM4B "reads" one and "erases" another so-called epigenetic mark on a single histone protein during the generation of sex cells in mice. The researchers say the finding may one day shed light on some cases of infertility and cancer. A summary of the work, a collaborative study among researchers at the Johns Hopkins University School of Medicine, Rice University and the University of Wisconsin-Madison, was published online in the journal Nature Communications on Nov. 14. "Our research gives us insight into how cells use this epigenetic machinery to shut off and protect parts of the genome during reproduction," says Sean Taverna, Ph.D., associate professor of pharmacology and molecular sciences at the Johns Hopkins University School of Medicine. "Because KDM4B and its histone target are prevalent in mouse testes, and the absence of that histone target inhibits reproduction in a single-celled organism, we think this interaction could play a role in human infertility or other diseases." At the heart of their new discovery, says Taverna, is the fact that genes housed in a cell's nucleus are not the whole story when it comes to the proteins they ultimately make. If genes are the sentences of a book, the story can be altered dramatically depending on which sentences are read and skipped over, and in what order. Histone proteins, Taverna explains, act like removable tape sealing closed particular pages of the book. When DNA is wrapped around them, genetic regions are "silenced" and go unread by other proteins -- a classic epigenetic control mechanism, since it changes how the genome is read without changing its sentences. Histones are frequently controlled through small chemical "tags," especially methyl groups, which can be attached to and detached from specific spots on histone proteins. To advance its understanding of this process, Taverna's lab had previously turned to a one-celled organism, Tetrahymena thermophila, with an unusual trait: It has not one but two nuclei. The DNA in one nucleus is active and used for making proteins, while the DNA in the other is "silent" except during mating. That research revealed a new site for methyl groups on one histone. That spot, a lysine known as H3K23, has little to no methyl tags in active Tetrahymena nuclei but is loaded up with three methyl groups (H3K23me3) in "mating nuclei" undergoing early meiosis, the special version of cell division that creates sex cells. In those experiments on Tetrahymena, the team learned that H3K23me3 appears in regions of the genome that should never be cut by enzymes during meiosis. DNA cuts normally occur during meiosis to allow for the mixing of genetic material and the proper sorting out of chromosomes in dividing cells, so H3K23me3 could protect nearby regions of the genome by "taping them up" so they can't be accessed. In a hunt for what controls that part of the process, researchers at the University of Wisconsin-Madison led by John Denu, Ph.D., developed a way to find out which proteins bind to which histone tags. Specifically, they identified a family of three similar enzymes called lysine demethylases, or KDM4s, which have been implicated in the development of some cancers in humans. KDM4A binds H3K23me3 plus two other histone tags and KDM4C binds another histone tag, but KDM4B binds only H3K23me3. The researchers wondered what feature enables the three KDM4s to be so selective in their binding, so colleagues at Rice University, led by George Phillips, Ph.D., picked up the research baton at that point to understand their selectivity by solving their 3-D structures. While KDM4B's structure proved elusive, the scientists were able to figure out the structure of KDM4A bound to H3K23me3. By comparing the differences between the KDM4s and by tweaking three of KDM4A's amino acid building blocks to make it act like KDM4B, the scientists report they were able to learn the basis for the binding preferences of all three KDM4s. "Now that we know the 'rules' that determine how KDM4s bind, we can imagine ways to intervene to change their interactions with histone tags," says Taverna. "That in turn means we can test what happens when we enhance their activity or turn it down, and better understand their roles in disease." To that end, biochemical tests revealed that after KDM4B "reads" H3K23me3, it "erases" the methyl groups from a nearby lysine, H3K36me3. The researchers say that more work is needed to understand the significance of this rare combination of activities, but Taverna speculates that the "demethylation" -- that is, removing the epigenetic marks -- of H3K36 helps to "tape up," silence and protect nearby DNA. "We know from our work in Tetrahymena that H3K23me3 is most often found in regions of the genome that should never suffer DNA damage because that would harm reproduction," he says. "During meiosis, when H3K23me3 is most prevalent, DNA is prone to damage, which explains why Tetrahymena lacking H3K23me3 struggle to reproduce." To see if H3K23me3 plays a role in mammalian reproduction, Taverna's group, led by postdoctoral fellow Kimberly Stephens, Ph.D., looked for its prevalence in rodents and found it and KDM4B to be increased in immature sperm undergoing early meiosis. (Since early meiosis occurs in females as they develop in the womb, the team was unable to examine immature eggs.) "While our experiments offer no proof that defects in the KDM4B-H3K23me3 interaction cause infertility in mammals, all of the signs point in that direction," says Taverna, "and we definitely plan to study it further." Other authors of the report include Romeo Papazyan, Ana Raman and Jeremy Thorpe of the Johns Hopkins University School of Medicine; Zhangli Su, Jin-Hee Lee, Kimberly Krautkramer, Melissa Boersma and Vyacheslav Kuznetsov of the University of Wisconsin-Madison; Fengbin Wang and Mitchell Miller of Rice University; and Ekaterina Voronina of the University of Montana.
Newswise — A common cause of hair loss and breakage known as acquired trichorrhexis nodosa, or TN --often more prevalent in African-Americans -- can actually be remedied through appropriate use of cleansing products, hair care and styling practices, say researchers at Johns Hopkins. "It's imperative that we offer dermatologist and patients alike easy tips for resolving TN, one of the few forms of hair loss that can be resolved fairly quickly with nonmedical options," says Crystal Aguh, M.D., assistant professor of dermatology at the Johns Hopkins University School of Medicine and co-author of Fundamentals of Ethnic Hair: The Dermatologist's Perspective. "Our recommendations are acceptable for those of all ethnic backgrounds experiencing hair breakage, and dermatologists should feel comfortable discussing these techniques with every patient seen." In a literature review published ahead of print in the Journal of Dermatological Treatment, the investigators outline risk factors and simple recommendations for dermatologists, who are often uncomfortable with advising patients, especially those of color, on appropriate practices necessary for avoiding hair loss and breakage. In the report, researchers analyzed the risk factors for TN. They found that thermal styling tools, such as the use of flat irons and blow dryers, as well as chemical processing, such as permanent dye and straightening, tend to damage the protective outer layer of the hair shaft, called the cuticle. This can alter the hair's protein structure, which causes the cortical fibers to be exposed and fray, leading to weak points where breakage occurs. Patients of African heritage (African-American and Afro-Caribbean) who tend to have tightly coiled hair are at increased risk for hair loss and damage from TN. This is because there are structural differences within the hair shaft -- African hair fibers have an asymmetric shape and curvature, resulting in points of geometric weakness in the hair shaft. Curly hair also has differences in hydration properties, causing it to be drier and more susceptible to breakage. Cleansing is the cornerstone of any health hair regimen, says Aguh. Inadequate cleansing of the hair and scalp can result in the buildup of product residue, leading to problems such as seborrheic and irritant dermatitis. As part of the literature review, investigators also describe simple over-the-counter, nonmedical remedies that can be recommended by dermatologists when treating patients with TN. First, choosing the appropriate shampoo based on hair types, the researchers say, is incredibly important when trying to reduce breakage and loss. Most shampoos include surfactants, which are the active ingredients that bind sebum and water. There are three types of surfactants to look for when selecting a shampoo -- anionic, amphoteric and nonionic. Anionic surfactants tend to be best suited for those with oily hair and are very effective at cleansing the hair, but this can leave the hair feeling dry and prone to breakage. Nonionic or amphoteric surfactants are recommended for those with natural black hair or dry, damaged or color-treated hair. These types of shampoos are gentler and less likely to strip the hair of moisture. Second, the frequency at which the hair is cleansed is key in minimizing the impact of TN. Frequency varies greatly based on many factors, such as age, ethnic origin and condition of the hair. Those with tightly curled hair types should shampoo their hair less frequently, since sebum has a harder time coating this particular type of hair strand. Patients with straight hair should shampoo more frequently because sebum coats the entire strand, leading to oily hair. "Patients with dry, damaged or tightly curled hair should limit their shampooing to no more than once per week. Those with straight hair, however, can shampoo daily," recommends Aguh. Third, conditioning the hair is arguably one of the most important steps for a healthy hair regimen, say the investigators. Conditioners increase hair manageability, help eliminate static electricity and can temporarily mend hair shaft damages. They come in many different formulations depending on the desired effect -- rinse-out, deep, leave-in and protein-containing. Rinse-out conditioners are applied immediately after the use of shampoo and rinsed out with water. While rinse-out conditioners increase manageability and add shine, they're less effective in repairing hair damage due to their short contact time with the hair. Unlike rinse-out, deep conditioners are left on the hair for at least 10 minutes and include the use of heat. Since they are usually formulated as deep creams, they enhance moisture in the hair. Deep conditioners are beneficial for severely damaged hair. Leave-in conditioners are put in the hair after shampooing and conditioning, and are not rinsed out. Leave-ins can be applied daily and are ideal for preventing damage from everyday grooming. The most beneficial conditioning treatment for those with dry and damaged hair is protein-containing conditioners. These can be formulated as rinse-out, deep or leave-in. Though protein-containing treatments help with breakage, it is recommend to only apply on a monthly or bimonthly basis, since overuse can lead to brittleness. Lastly, another way to help minimize hair breakage and prevent or treat TN is to try the repurposed soak-and-smear method for hair care. This method increases moisture retention, which in return enhances hair elasticity and reduces tangles. It forms increased protection from damage. The repurposed soak-and-smear method for hair care is as follows: 1. Shampoo and/or condition the hair normally and lightly blot hair with a towel.2. Follow with the application of a water-based leave-in conditioner to the hair.3. Immediately apply an oil or thick, occlusive moisturizer, such as coconut oil, olive oil, jojoba oil, petrolatum or mineral oil, to the hair.4. Allow the hair to air dry and style as desired. This method can be completed as often as needed throughout the week and modified depending on shampoo/conditioning needs. The repurposed soak and smear is especially beneficial for patients with tightly coiled hair, as it helps reduce dryness associated with overprocessing from heat and chemical applications. These recommendations can greatly improve the hair condition of those with TN. Since hair is a nonliving tissue, total repair of the hair shaft is not possible. Implementation of proper cleansing and conditioning techniques, as well as proper product selection, improve the overall health of hair, making it more resilient to trauma. "Patients need to be advised on how to improve the quality of their cleansing and conditioning routines," says Aguh. "These are the foundation of a healthy hair routine." Additional authors of this study include Shawn G. Kwatra of the Johns Hopkins University School of Medicine and Alessandra Haskin of Howard University College of Medicine.
Newswise — FAYETTEVILLE, Ark. – A team of biomedical engineering researchers at the University of Arkansas have identified a cause of fluid swelling of the brain, or cellular edema, that occurs during a concussion. The researchers discovered that pre-treating the cells with an existing, FDA-approved drug used for epilepsy and altitude sickness reduces the expression of a specific protein that causes swelling. Their findings were published in a recent issue of Nature’s Scientific Reports. “Our study found that mild traumatic brain injury resulted in increased expression of a protein called aquaporin-4, which caused a massive cellular influx of fluid, leading to increased astrocyte cell volume and injury,” said Kartik Balachandran, assistant professor of biomedical engineering. “We then worked with a drug called Acetazolamide. Our results showed that Acetazolamide minimized cell swelling and injury, suggesting a therapeutic role for this drug in reducing the detrimental effects of concussions.” In addition to Balachandran, who led the study, the research was conducted by Nasya Sturdivant, biomedical-engineering doctoral candidate; Jeffrey Wolchok, assistant professor of biomedical engineering; and partners at the FDA’s National Center for Toxicological Research in Jefferson, Arkansas. Mild traumatic brain injury, also known as a concussion, is a devastating condition that is commonly experienced in car accidents, full-contact sports and battlefield injuries. One of the main factors that leads to the high death rate in patients who experience mild traumatic brain injury is the swelling or edema of astrocytes, the most abundant cell type in the brain. The researchers engineered a benchtop bioreactor to examine astrocyte cells. This device helped them see that mild traumatic brain injury led to an increased expression of aquaporin-4, the protein that causes a large cellular influx of fluid, which in turn leads to increased astrocyte cell volume. “This study demonstrates the collaborative neuro-engineering efforts that are contributing to both diagnostic and therapeutic methods for addressing traumatic brain injury,” said Raj Rao, professor and chair of the Department of Biomedical Engineering at the University of Arkansas. The research was funded by the National Science Foundation. -30- CONTACTS: Kartik Balachandran, assistant professor, biomedical engineeringCollege of Engineering479-575-3376, email@example.com Matt McGowan, science and research communications officerUniversity Relations479-575-4246, firstname.lastname@example.org SEE ORIGINAL STUDY
Loyola Medicine Julia Conkin suffered a childhood bout with the flu that triggered progressive hearing loss. Matt Kircher, MD, an ear, nose and throat surgeon at Loyola, implanted a cochlear implant in a one-hour outpatient surgery. She now is able to hear conversations and listen to music without the use of a hearing aid. Source Newsroom: Loyola University Health System Newswise — MAYWOOD, IL – Due to a childhood bout with the flu, Julia Conkin suffered progressive hearing loss that started in her left ear and continued to her right ear. ”I couldn’t hear conversations or even listen to music without the use of a hearing aid, and due to my worsening condition, hearing aids weren’t even working well," Ms. Conkin said. Ms. Conkin consulted with the multidisciplinary otolaryngology and audiology team at Loyola Medicine.“Julia’s hearing was so bad she had to rely on sign language and that severely limited the number of people she could communicate with,” said Loyola audiologist Adriana Russ, AuD. “She came to Loyola to see if she was a candidate for a cochlear implant.” Matt Kircher, MD, an ear, nose and throat surgeon, implanted a cochlear implant in a one-hour outpatient surgery. “Julia had suffered from really bad hearing for a very long time and was at the end of her rope and looking for the next step,” said Dr. Kircher. "A cochlear implant is a device usually used in patients like Julia who have failed hearing aids.” Unlike a traditional hearing aid, a cochlear implant does not make sound louder or clearer; rather it bypasses the damaged parts of the auditory system and stimulates the hearing nerve, allowing sound to be received. The cochlear implant system contains two parts: the external processor and the internal implant. The external processor is worn behind the ear and includes a speech processor, a microphone and a battery compartment. The internal implant is surgically placed under the skin behind the ear. These two parts work together to allow for the perception of sound. Dr. Kircher has performed hundreds of cochlear implants. He makes a small incision behind the ear, exposing the cochlea. Then, an opening is made in the cochlea and the electrodes for the implant are inserted. The internal implant is then placed beneath the skin. A few weeks after implantation, Dr. Kircher and the team place the external processor, microphone and implant transmitter. A Loyola audiologist activates the implant. “With Julia, the expectations for hearing improvement were modest but the results were spectacular,” said Russ. Ms. Conkin calls her cochlear implant a life-changer. "I noticed almost immediately after my implant was activated that I could hear things I had not heard for years, like music and conversations at gatherings,” she said. “It was beautiful to hear other people.” Loyola Medicine is nationally recognized for its expertise in diagnosing and treating a broad range of ear, nose and throat conditions and providing integrated services for optimal patient care.
STUDY SHOWS LOW-DOSE CHEMOTHERAPY REGIMENS COULD PREVENT TUMOR RECURRENCE IN TYPES OF BREAST CANCER AND PANCREATIC CANCER
Newswise — Conventional, high-dose chemotherapy treatments can cause the fibroblast cells surrounding tumors to secrete proteins that promote the tumors’ recurrence in more aggressive forms, researchers at Taipei Medical University and the National Institute of Cancer Research in Taiwan and University of California, San Francisco, have discovered. Frequent, low-dose chemotherapy regimens avoid this effect and may therefore be more effective at treating certain types of breast and pancreatic cancer, according to the murine study “Metronomic chemotherapy prevents therapy-induced stromal activation and induction of tumor-initiating cells,” which will be published online November 23 in The Journal of Experimental Medicine. Chemotherapy drugs are usually administered to cancer patients every few weeks at a high “maximum tolerated” dose. Though this approach kills the majority of tumor cells, it often spares a small number of tumor-initiating cells (TICs) that subsequently give rise to new tumors. Moreover, these recurring tumors are often more aggressive and able to metastasize to other tissues, in part because high doses of chemotherapy drugs also affect cells in the stromal tissue that surrounds tumors, including immune cells and blood vessel endothelial cells. Kelvin Tsai at Taipei Medical University and Valerie Weaver at the University of California, San Francisco, decided to investigate the effect of chemotherapy on fibroblasts, a major component of the stroma in desmoplastic tumors such as breast cancer and pancreatic ductal adenocarcinoma. The researchers found that, in response to the maximum tolerated doses of several commonly used chemotherapy drugs, breast cancer–associated fibroblasts secrete large amounts of cell signaling proteins called ELR+ chemokines. These proteins promoted tumor growth and metastasis in mice by converting neighboring cancer cells into TICs, stimulating the formation of blood vessels within the tumor and enhancing the recruitment of immune cells called macrophages. Recent studies have suggested that treating patients with low doses of chemotherapy drugs at more frequent, even daily, intervals may be more effective than traditional chemotherapeutic approaches. Tsai and colleagues found that such “low-dose metronomic” regimens did not induce the production of ELR+ chemokines by cancer-associated fibroblasts. This, in turn, reduced the fibroblasts’ ability to promote TIC formation, blood vessel growth, and macrophage recruitment. Mice with breast cancer or pancreatic ductal adenocarcinoma therefore responded better to low-dose metronomic chemotherapy, surviving longer than mice treated with the maximum tolerated dose. “Our results lend support to the emerging paradigm that stroma-derived signals contribute to tumor pathology,” Tsai says. “They also suggest that low-dose metronomic chemotherapy or targeting the chemokine signaling mediated by chemo-treated fibroblasts may improve the therapeutic outcome in desmoplastic cancers.” Chan et al. 2016. J. Exp. Med. https://doi.org/10.1084/jem.20151665 # # #
Newswise — ANN ARBOR, Mich. – Planning a holiday meal can be hectic, and some families will be managing an extra stressor: accommodating the dietary restrictions of teens on gluten-free, vegan or other special diets. For a variety of reasons, many teens choose diets that go beyond cutting calories and reducing portion sizes – instead, these special diets restrict entire food groups. That could mean added costs and new logistical challenges for families, suggests a new national poll. One in six parents say their teen has tried a diet that is vegetarian (9 percent), gluten-free (6 percent), vegan (4 percent) or paleo (2 percent) at some point in the past two years, according to the C.S. Mott Children’s Hospital National Poll on Children’s Health at the University of Michigan. The diet changes weren’t always harmonious. Roughly half of parents in the Mott poll said the special diets caused conflicts at holiday and family gatherings. “Teen diets that limit food options can impact the whole family,” says poll co-director Sarah Clark, M.P.H. “That can lead to conflict at the holidays if the diet doesn’t include the mainstays of the family’s traditional meal, and the teen refuses to eat Granny’s famous mac & cheese, or the turkey Aunt Emma spent all day preparing.” Other difficulties are everyday challenges, like finding a suitable place for the whole family to dine out (61 percent), extra time spent preparing diet-friendly food (55 percent), the stress of family members eating different meals (54 percent) and the added expense of buying special diet foods (50 percent). “Parents can work with teens to minimize any burden on family members, such as asking the teen to prepare his or her own meals, or finding diet-compliant versions of the family’s favorite foods,” says Clark. Too little health advice? Parents gave a variety of reasons for why their teen tried the special diet: 32 percent said it was health-related, while 29 percent said it was because another family member was on the same diet. Other motives included a friend’s suggestion (17 percent) and the diet’s environmental impact (14 percent). More than half of parents say they did their homework when their teen started a special diet — with nearly half suggesting that their teen began taking vitamins or supplements in tandem. Just 17 percent brought their teen to a health care provider to discuss whether the diet was healthy. “Parents may not recognize this as a situation that would benefit from advice from a health care professional,” says Clark. About half of parents (52 percent) think the special diet had a positive impact in their teen feeling healthier, while 41 percent believe it made no difference. On the other hand, 7 percent say the diet negatively impacted their teen’s health. “There are situations where diets that restrict certain food groups can result in teens not getting enough protein, iron, calcium or other essential parts of a healthy diet,” said Clark. “Advice from a dietician or nutritionist can help families weigh the risks and benefits to determine practical options for teens looking for a healthier lifestyle.” The Mott Poll report was based on responses from a nationally-representative group of 910 parents who had at least one child between the ages of 13 and 18.