Why they fly
Brown University researchers Kenneth Breuer and Sharon Swartz, fascinated by the aerodynaic flight of bats, recently obtained some unprecedented views of these mammals. They combined video recordings with precise measurements of the wake field generated by the bats' wing movements to highlight ways that bat flight differs from bird and insect flight. Bats "can generate different wing shapes and motions that other creastures can't," said Breuer, whose research appears in the current issue of Bioinspiration and Biomimetics. The researchers are awaiting a much faster laser that will help them to better understand the mechanism of a bat’s flight and allow them to examine takeoff, turning, and landing in detail.
GERIATRICS
Older people taking antidepressants are at greater risk of breaking bones
Past studies have suggested that a class of commonly prescribed antidepressants that includes the drugs Prozac and Zoloft increased the risk of bone fractures in the elderly. Now, a study led by researchers at McGill University suggests that those drugs, known as selective serotonin reuptake inhibitors, or SSRIs, may increase the risk of fracture by changing the physiology of bone. Researchers examined data from more than 5,000 patients aged 50 years or older. Over a five-year period, patients who took SSRIs daily were twice as likely as those who didn't to experience a "fragility fracture," a break that occurs with a minimal amount of trauma . "It suggests that the bone is excessively susceptible to fractures," author Dr. David Goltzman said. The study showed a decrease in bone density; however, Goltzman said that even when researchers took the decreased density into account, the risk of fracture was still unexpectedly high . "The working hypothesis, he said, is that SSRIs "interfere with the ability of bone cells to make bone properly."
BOTTOM LINE: A commonly used class of antidepressants may affect the growth of bone, putting elderly patients at an increased risk of bone fracture. Doctors should talk to their patients on SSRIs about ways to reduce the risk of fractures, Goltzman said.
CAUTIONS: The data did not address the duration of patients' daily use of SSRIs . The study was partially funded by companies that make SSRIs.
WHAT'S NEXT: Researchers want to examine the ways in which SSRIs affect bone density and quality.
WHERE TO FIND IT: Archives of Internal Medicine, Jan. 22.
MICHELLE SIPICS
PEDIATRICS
Inhaled steroids are the best treatment for a child with mild to moderate asthma
Children with asthma are given one of several medications, but until now, the effectiveness and safety of these treatments had not been compared. In a study of 285 children ages 6 to 14 with mild to moderate asthma, researchers at the National Heart, Lung, and Blood Institute found that inhaled steroids were the most effective initial daily treatment. Comparing the efficacy of three treatment regimens -- a low-dose inhaled steroid (Flovent), a lower dose of the same inhaled steroid combined with a beta agonist (the drugs Advair and Serevent), and an oral leukotriene receptor antagonist (Singulair) -- the researchers found that after 48 weeks the children treated solely with Flovent showed lower frequencies of symptoms and better lung functioning than children in the other two groups. In contrast to previous studies suggesting inhaled steroids might impair growth, the researchers found no significant impacts on growth among any of the medicines. "This study adds more confidence to inhaled steroids as an effective asthma treatment," said Virginia Taggart, the project officer for the study.
BOTTOM LINE: "The most obvious question asthma patients have is what is the best medication, and this research gives reassurance" that inhaled steroids " are both effective and safe," Taggart said.
CAUTIONS: A larger sample size might have revealed a wider variation in response to treatment.
WHAT'S NEXT: The researchers are studying ways of making the inhaled steroid treatment even more effective, either by boosting the dosage or by combining a low dose with other medications.
WHERE TO FIND IT: Journal of Allergy and Clinical Immunology, January.
AMI ALBERNAZ
