Each year, it is estimated, about 1 million people who have coronary artery disease undergo some type of surgery unrelated to that condition. Of those, about 50,000 suffer heart attacks in the days and weeks after surgery, and of those, about 20,000 die.
Doctors have long sought a way to predict which patients were most likely heart attack candidates so they could be given special care to prevent the attacks.
It appears now that researchers at the University of California at San Francisco have found a way to identify many of these high-risk patients. Dr. Dennis Mangano and colleagues monitored patients right after surgery to look for those whose hearts suffered from insufficient oxygen delivery, a condition doctors call ischemia. These patients are nine times as likely to have heart attacks in the days after surgery as others with coronary artery disease who don`t experience ischemia right after surgery.
Clues to PMS
The depression, irritability and other mood disturbances in women that sometimes are labeled as premenstrual syndrome, or PMS, may actually be rooted in sleeplessness, an article in the journal Sleep reports, and another study suggests that secretions of a brain chemical may play a role.
In a study at the University of Washington in Seattle, scientists compared sleep patterns of one group of young women who suffer from PMS with those of another group of women who don`t have PMS symptoms. While on average the women in both groups slept seven hours a night, those in the PMS group were more restless and experienced less of the deeper, restful stages of sleep and more lighter stages.
”All women who ovulate experience monthly hormonal changes,” said Dr. Kathryn Lee, who headed the study. ”But those who don`t get deep sleep may be less able to cope with those hormonal changes.”
Meanwhile, a study published in the Archives of General Psychiatry found certain abnormalities in the timing and release of melatonin among women with PMS. Melatonin is a neurohormone secreted at night by the pineal gland in the center of the brain, an organ associated with control of a person`s circadian rhythms. It is known that melatonin can play a role in controlling sleep patterns, but further study will be needed to determine if the two groups of researchers have together discovered the underlying cause of PMS.
Instant messaging
A record for generating light pulses with a laser has been achieved by AT&T Bell Labs, which has produced 350 billion light pulses a second. That exceeds the 2.5 billion light pulses a second used commercially to send messages down thin glass optical fibers.
The achievement hints at the future of information-technology improvements in the coming decade, said Won-Tien Tsang, head of Bell`s semiconductor electronics research department.
”If you extrapolate current progress in bit-rate into the future by recalling that our transmission systems were at 45 megabits (million bits) in 1980 and that the research limit is at 350 gigabits (billion bits) today, you can predict that we`ll reach a terabit-1,000 gigabits a second-by the year 2000,” Tsang said.
Relief for skin
A painful skin disorder sometimes associated with an outbreak of shingles may be treated with a new gel concocted by a northern California pharmacist who wanted to relieve his wife`s suffering.
Researchers at the University of Califorinia at San Francisco, conducting trials of the gel made by a Los Altos pharmacist, hope it will prove more effective than anything previously available to treat post-herpetic neuralgia, a skin condition so painful that victims find it hurts just to wear clothes. The gel, which contains a commonly used local anesthetic called lidocaine, apparently can desensitize nerve fibers for hours, killing the pain, which afflicts several hundred thousand people each year.
”It is very difficult to treat,” said Dr. Michael Rowbotham of the university, ”and many physicians don`t know the most effective things to try.”
Ignoring risk
A woman`s risk of breast cancer increases as she grows older, and most health authorities agree that women older than 65 should have both a physical examination by a physician and an X-ray exam annually. But older women often don`t get the recommended exams.
A study of 1,066 women older then 65 by researchers at the University of Buffalo found that two-thirds didn`t get the recommended exams. Even in women who had a history of breast cancer, only 62 percent had X-ray mammograms.
Humane handcuffs
Permanent damage to peripheral nerves in the wrist can result from overly tight application of handcuffs, a study in the journal Neurology discloses.
In five cases detailed by neurologists at the Washington Hospital Center in Washington, D.C., the overtight applications of cuffs was associated with prisoner behavior. In each documented case, ”the injured individual was intoxicated, belligerent or uncooperative with police prior to or during the arrest,” said Dr. Robert Laureno, one of the report`s authors. ”Under these circumstances, the gentle application of handcuffs is not a priority concern of arresting officers. Police behavior is also a factor in these injuries. In one case, the arresting officer was so angered by an individual`s behavior before his arrest that he used unnecessary force when applying the
handcuffs.”
Most handcuffs are designed so that struggling by the prisoner can easily result in overtightening, the report noted. A newer design of cuff that automatically double-locks on application, preventing overtightening, is available, the researchers noted.
Pesticide study
If American farmers stopped using half the chemical pesticides they now spray on crops, it would cause only a slight rise in food prices and would bestow major environmental and public health benefits, a Cornell University study concludes.
The study, an economic and environmental analysis of information from more than 300 agricultural scientists and economists, estimates that a 50 percent reduction in chemical pesticide use would produce an increase in food prices of only 0.6 percent.
”Furthermore, the environmental and public health benefits of reducing pesticide use would more than balance this cost and actually provide net benefits to the economy,” said David Pimental, a Cornell entomologist who was a study leader. ”The American public has indicated in numerous opinion polls that they are willing to pay slightly more for food if they could be assured that pesticides in the food and the environment were greatly reduced.”
