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MEMPHIS, May 12 (UPI)—U.S. scientists said their findings about how sounds are amplified in the inner ear might explain how genetic mutation or drug-overdose hearing loss occurs. St. Jude Children's Research Hospital investigators found an electrically powered amplification mechanism in the cochlea of the ear is critical to the acute hearing of humans and other mammals. Sound entering the cochlea is detected by the vibration of tiny, hair-like cilia that extend from cochlear hair cells, the scientists said. While the cochlea's "inner hair cells" are only passive detectors, the so-called outer hair cells amplify the sound signal as it transforms into an electrical signal that travels to the brain's auditory center, they said. Without such amplification, hearing would be far less sensitive since sound waves entering the cochlea are severely diminished as they pass through the inner ear fluid. The research, which included Jian Zuo, Xudong Wu, Jiangang Gao and Wendy Cheng at St. Jude; Peter Dallos, Mary Ann Cheatham, Jing Zheng, Charles Anderson and Soma Sengupta at NORTHWESTERN University; and Shuping Jia, Xiang Wang and David He at Creighton University, appears in the May 8 issue of the journal Neuron. Men, the joke goes, spend the first half of their lives making money and the second making water. That is because after age 50 many men face an embarrassing problem called B.P.H., for benign prostatic hyperplasia. This slowly progressive enlargement of the prostate can make urination difficult or painful and send men trudging to the bathroom many times during the day and night. Though bothersome, B.P.H. is not life threatening. Nor does it lead to cancer. When left untreated, however, B.P.H. can lead to serious health problems for some. "There is a big difference between having the symptoms and being bothered by the symptoms," said Dr. Kevin T. McVary, professor of urology at the Feinberg School of Medicine at NORTHWESTERN University. "Some men go to the bathroom several times a night, get right back to sleep and are not bothered," he said. Watchful waiting, or monitoring symptoms while holding off on medical or surgical treatments, is a reasonable plan for these men, he added. But for patients who have trouble getting back to sleep, "there are many effective options, and patients almost always end up with less bothersome symptoms once they choose to do something," he said. Dr. Boyd E. Metzger from NORTHWESTERN University's Feinberg School of Medicine in Chicago and colleagues also found that the higher the mother's blood sugar levels, the more likely the women were to develop a potentially serious condition called preeclampsia marked by a spike in blood pressure and the more likely their infants were to be born prematurely and to experience shoulder dystocia—a condition in which an infant's shoulder becomes lodged inside the mother's body, effectively halting the birth process. "These relationships are continuous and generally increase incrementally over the range of blood (sugar) levels we saw in the study," Metzger noted in a statement. The question remains, Metzger told Reuters Health, "at what level of risk should we intervene? That is a big question that can't be addressed by this research." He noted that a meeting to discuss these issues is scheduled next month immediately following the annual meeting of the American Diabetes Association. The diabetes pill metformin is just as effective as insulin injections in treating women who develop diabetes during pregnancy, researchers in New Zealand and Australia reported on Wednesday. So-called gestational diabetes surfaces in one out of every 20 pregnant women, and there has been concern that metformin might affect a fetus because the drug can cross the placenta. The team, led by Dr. Boyd Metzger of NORTHWESTERN University in Chicago, also found a link between blood sugar levels and problems such as premature delivery and birth injury, along with an increased likelihood that a newborn would end up in intensive care. "These are well-recognized complications of pregnancies in mothers with preexisting or gestational diabetes, as currently defined," the researchers wrote. The typical results of treatment are an increase in energy, decreased body fat, increased libido, and an improvement in mood. And earlier this year, Harvard Men's Health Watch reported that testosterone replacement may be related to improved mental acuity. But Kevin McVary, professor of urology at NORTHWESTERN University's Feinberg School of Medicine, cautioned that testosterone-replacement therapy remains controversial. "Potential risks include enlargement of the prostate, problems voiding, acne, and hot flashes," McVary explained. "Uncommon but dangerous side effects may include stroke or prostate cancer. Also those who suffer from congestive heart failure may notice a worsening of their symptoms." And recent studies have shown testosterone replacement therapy is not as effective in men over 70. McVary also noted, however, that no evidence exists to suggest that testosterone-replacement therapy will be wrought with the backlash of cancer and heart disease associated with the federal Women's Health Initiative, which halted a hormone-replacement therapy study involving women in 2005. For six months, many of them remained nameless and that seemed only right. It would be disrespectful to completely wipe away who they were when they were alive. To pick some silly name would be degrading, the faculty implored them. Medical student Emily Zander was always mindful to say "she" instead of "it." But there was another reason that many of the 175 students in NORTHWESTERN University's Feinberg School of Medicine's anatomy lab didn't want to name their cadavers. It was too personal. They knew only the age and cause of death, and there needed to be some distance when, for example, removing the ribs to look at the heart and lungs. CHICAGO, May 1 (UPI)—A U.S. researcher is using zebrafish to test drugs that may help people with tinnitus regain normal hearing. Ernest Moore, an audiologist and cell biologist at NORTHWESTERN University, says zebrafish have ears, which are remarkably similar to humans' ears. Moore has been able to cause ringing in the ears of zebrafish by exposing them to certain drugs and tracking their erratic swimming on video. Moore then looks at the cells in their ears to see if the electrical firing has increased, an early sign of damage and tinnitus. Moore's early findings show an increased firing. Moore is discussing a clinical trial to test these drugs for patients with tinnitus, or ringing in the ears. "If these drugs are found to be safe—and some are already on the market for other uses—and if they are found to have efficacy in humans, then they might be used to treat an individual's tinnitus," Moore said in a statement. "If the hair cell—sensory receptors in the ear that vibrate to amplify sound—is not totally damaged—just beginning to break down, and you administer these drugs, you might be able to prevent it from further damage and interfere with the cells' ability to generate tinnitus." Pfizer has reduced its R&D from 15,000 people worldwide to about 12,000 in the last year and a half. So, that means the company is leaning on research partners because of pressure to reduce development costs and lower prices. For instance, a new Pfizer drug for treating fibromyalgia, was licensed out of NORTHWESTERN University, Rosen said. Dementia in people younger than 65 isn't always the result of early-onset Alzheimer's disease. Frontotemporal lobar degeneration, or FTLD, an umbrella term that covers several brain disorders, is another cause of early dementia, although one that is not widely recognized. Both Alzheimer's disease and FTLD cause brain cells to die. However, because they affect different regions of the brain, each triggers distinct abnormalities, said Sandra Weintraub, PhD, professor of psychiatry and behavioral sciences and neurology at NORTHWESTERN University's Feinberg School of Medicine in Chicago. Both early-onset Alzheimer's and FTLD cause additional family turmoil when it comes to finding long-term care because these patients are so much younger than the average nursing home patient, said Darby Morhardt, a research associate professor at NORTHWESTERN's Feinberg School of Medicine. Nursing homes sometimes don't accept patients younger than 65, Morhardt said. Plus the odd behavior of some FTLD patients may make it difficult for staff to control them. Even when services are available, they may not be appropriate. "The evidence suggests that younger people have different needs," she said. People in their 40s and 50s are active, and frequently no programs exist for them, even in adult day-care facilities, said Morhardt. The lack of public awareness of FTLD also can trigger unhelpful responses, she added. The patient may be arrested after an angry outburst or disability benefits may be denied because the disease has been misdiagnosed. Families also cite problems negotiating the health care system. "The medical community isn't there for them," said Morhardt, who has conducted a survey of caregivers.
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| This page last updated onMay 14, 2008
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