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Archive - Sep 7, 2014

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Method to Create New Muscles Developed, Holds Promise for Treatment of Muscle-Wasting Diseases

Researchers at the Sanford-Burnham Medical Research Institute (Sanford-Burnham) in La Jolla, California have developed a novel technique to promote tissue repair in damaged muscles. The technique also creates a sustainable pool of muscle stem cells (image) needed to support multiple rounds of muscle repair. The study, published onine on September 7, 2014 in Nature Medicine, provides promise for a new therapeutic approach to treating the millions of people suffering from muscle diseases, including those with muscular dystrophies and muscle wasting associated with cancer and aging. There are two important processes that need to happen to maintain skeletal-muscle health. First, when muscle is damaged by injury or degenerative disease such as muscular dystrophy, muscle stem cells—or satellite cells—need to differentiate into mature muscle cells to repair injured muscles. Second, the pool of satellite cells needs to be replenished so there is a supply to repair muscle in case of future injuries. In the case of muscular dystrophy, the chronic cycles of muscle regeneration and degeneration that involve satellite-cell activation exhaust the muscle stem-cell pool to the point of no return. "Our study found that by introducing an inhibitor of the STAT3 protein in repeated cycles, we could alternately replenish the pool of satellite cells and promote their differentiation into muscle fibers," said Alessandra Sacco, Ph.D., Assistant Professor in the Development, Aging, and Regeneration Program at Sanford-Burnham. "Our results are important because the process works in mice and in human muscle cells.

Graphene-Based, Room-Temperature Detector Captures Unprecedented Range of Light, Including Terahertz Waves

New research at the University of Maryland could lead to a generation of light detectors that can see below the surface of bodies, walls, and other objects. Using the special properties of graphene (image), a two-dimensional form of carbon that is only one atom thick, a prototype detector is able to see an extraordinarily broad band of wavelengths. Included in this range is a band of light wavelengths that have exciting potential applications but are notoriously difficult to detect: terahertz waves, which are invisible to the human eye. A research paper about the new detector was published online on September 07, 2014 in Nature Nanotechnology. Lead author Xinghan Cai, a University of Maryland physics graduate student, said a detector like the researchers’ prototype “could find applications in emerging terahertz fields such as mobile communications, medical imaging, chemical sensing, night vision, and security.” The light we see illuminating everyday objects is actually only a very narrow band of wavelengths and frequencies. Terahertz light waves’ long wavelengths and low frequencies fall between microwaves and infrared waves. The light in these terahertz wavelengths can pass through materials that we normally think of as opaque, such as skin, plastics, clothing, and cardboard. It can also be used to identify chemical signatures that are emitted only in the terahertz range. Few technological applications for terahertz detection are currently realized, however, in part because it is difficult to detect light waves in this range. In order to maintain sensitivity, most detectors need to be kept extremely cold, around 4 degrees Kelvin, or -452 degrees Fahrenheit. Existing detectors that work at room temperature are bulky, slow, and prohibitively expensive.

UV Light-Induced Mutation in KNSTRN Gene Drives Many Skin Cancers, Stanford Study Shows

A genetic mutation caused by ultraviolet light is likely the driving force behind millions of human skin cancers, according to researchers at the Stanford University School of Medicine. The mutation occurs in a gene called KNSTRN, which is involved in helping cells divide their DNA equally during cell division. Genes that cause cancer when mutated are known as oncogenes. Although KNSTRN hasn't been previously implicated as a cause of human cancers, the research suggests it may be one of the most commonly mutated oncogenes in the world. "This previously unknown oncogene is activated by sunlight and drives the development of cutaneous squamous cell carcinomas," said Paul Khavari, M.D., Ph.D., the Carl J. Herzog Professor in Dermatology in the School of Medicine and Chair of the Department of Dermatology. "Our research shows that skin cancers arise differently from other cancers, and that a single mutation can cause genomic catastrophe." Cutaneous squamous cell carcinoma is the second most common cancer in humans. More than 1 million new cases are diagnosed globally each year. The researchers found that a particular region of KNSTRN is mutated in about 20 percent of cutaneous squamous cell carcinomas and in about 5 percent of melanomas. A paper describing the research was published online on September 7, 2014 in Nature Genetics. Dr. Khavari, who is also a member of the Stanford Cancer Institute and Chief of the dermatology service at the Veterans Affairs Palo Alto Health Care System, is the senior author of the paper. Postdoctoral scholar Carolyn Lee, M.D., Ph.D., is the lead author. Drs. Lee and Khavari made the discovery while investigating the genetic causes of cutaneous squamous cell carcinoma. They compared the DNA sequences of genes from the tumor cells with those of normal skin and looked for mutations that occurred only in the tumors.

Study ID’s Molecule That Induces Cancer-Killing Protein

A new study by University of Kentucky (UK) researchers has identified a novel molecule named Arylquin 1 as a potent inducer of Par-4 secretion from normal cells. Par-4 is a protein that acts as a tumor suppressor, killing cancer cells while leaving normal cells unharmed. Normal cells secrete small amounts of Par-4 on their own, but this amount is not enough to kill cancer cells. Notably, if Par-4 secretion is suppressed, this leads to tumor growth. To be published online on September 7, 2014 in Nature Chemical Biology, the UK study utilized lab cultures and animal models to show that low levels of Arylquin 1 induced Par-4 secretion without causing harm to the producer cells. Additionally, the researchers found that Par-4 is bound to a protein called vimentin, which contributes to tumor metastasis. Arylquin 1 binds to vimentin, displacing the Par-4 for secretion -- which means it may also be useful for inhibitiing the spread of cancer. These findings have strong implications for the development of future cancer treatments, as researchers are now focusing on developing Arylquin 1 into a drug to inhibit both primary and metastatic tumors. "We found that Par-4 is inactivated by pro-metastasis proteins such as vimentin," said Dr. Vivek Rangnekar, UK professor and Alfred Cohen Chair in Oncology Research in the Department of Radiation Medicine. "This implies that by using small molecule drugs that target metastasis proteins, we may be able to both inhibit the spread of cancer while also releasing the tumor suppressor -- Par-4 -- to then induce the death of the cancerous cells." Dr. Rangnekar, who also serves as Associate Director for the UK Markey Cancer Center, initially discovered the Par-4 gene in 1994. Working closely with UK medicinal chemist Dr.

Inexpensive Lab Tests Identify Resistant Infections Rapidly

Researchers from the Oregon State Public Health Lab have modified the protocol for a relatively new test for a dangerous form of antibiotic resistance, increasing its specificity to 100 percent. The research, confirming the reliability of a test that can provide results in hours and is simple and inexpensive enough to be conducted in practically any clinical laboratory was presented at the 54th Interscience Conference on Antimicrobial Agents and Chemotherapy, an infectious disease meeting of the American Society for Microbiology, held in Washington, D.C. September 5-9, 2014. The test, called Carba NP, originally developed by Drs. Patrice Nordmann and Laurent Poirel at the University of Fribourg, Switzerland, and Dr. Laurent Dortet of the University Hospital of the South-Paris Medical School, France, allows for rapid identification of carbapenem-resistant Enterobacteriaceae (CRE), often referred to in the media as "super bugs" for their ability to resist most major antibiotics. Carbapenems (see image) are an important class of powerful antibiotics for treating severe infections caused by multidrug-resistant Gram-negative bacteria. Carbapenemases are enzymes produced by some bacteria which inactivate these antibiotics. "Over the past decade carbapenemase-producing CRE (CP-CRE) have rapidly spread around the globe and are currently considered an urgent public health threat by the Centers for Disease Control and Prevention (CDC)," says Dr. Karim Morey of the Oregon State Public Health Lab, an author on the study.

61 Percent Drop in Female Genital Warts Attributed to Free HPV Vaccination Program in Australia

General practitioners in Australia are managing 61 per cent fewer cases of genital warts among young women since the introduction of the national human papillomavirus (HPV) vaccination program, a new study from the University of Sydney reveals. The study, which reviewed more than a million patient encounters between 2000 and 2012, showed a significant year-on-year reduction in the management rate of genital warts in women aged 15-27 years since the vaccination program started. The findings were published online on September 2, 2014 in the open-access journal PLOS ONE. "The results show that the program has been a widespread success," said lead author of the study Christopher Harrison of the University of Sydney. The HPV vaccination program was introduced in 2007, and the rate of genital wart presentation fell dramatically from 4.33 per 1,000 encounters pre-program (2002-2006) to 1.67 per 1,000 encounters in the post-program period (2008-2012). Australia was one of the first countries to provide the HPV vaccine free to young women through a national immunization program. The vaccine protects against two major viral causes of genital warts (HPV 6 and HPV 11) and two major viral causes of cervical cancer (HPV 16 and HPV 18). "This is the first study to report the impact of HPV vaccinations on genital warts management in general practice, which is where the majority of cases are treated," said Mr. Harrison. "We looked at women potentially covered by the vaccination program (15-27 years), and the data showed a 61 per cent decrease in the management rate of genital warts in the four years after the program started, compared with the four years before the program. "This is an excellent result as not only do genital warts cause distress in affected patients, but treatment is at a substantial cost to the health system.