Jewish World Review Jan. 25, 2002 / 12 Shevat, 5762




Drug increases lifespan (if you're a fly...)

By Robert A. Wascher, M.D., F.A.C.S.

http://www.NewsAndOpinion.com -- FROM this week's Proceedings of the National Academy of Sciences is an intriguing study of life extension through the use of a drug. The drug, 4-phenyl butyrate (PBA), binds to the genetic material in the nucleus of cells, and is known to activate some genes that are normally inactive in adult cells, while shutting down other genes that are normally active. In this study, fruit flies were fed a diet consisting of "fly chow" and PBA throughout their lifetime, and average and maximal life spans were then calculated for these flies.

Compared with control flies not fed PBA, the PBA-fed flies exhibited significant increases in average lifespan. Moreover, the PBA-fed flies appeared as healthy and vigorous as their fly buddies that not receiving PBA. This life-extending effect was also observed after even limited periods of PBA feeding. The authors then assessed a panel of 7,500 fly genes, and found that flies exposed to PBA had about 100 genes activated and 48 genes inactivated when compared to flies not receiving PBA.

Although it was not possible to identify precisely which activated and/or inactivated genes played a role in the life-extending effects of PBA, these results suggest that a particular balance between activation and inactivation of certain genes can actually extend the lifespan of, at least, flies. Since the metabolism of fly cells is not terribly different from human cells, this study has important implications for human health.

Not only does this study provide important clues regarding the genetic determinants of lifespan, but it also suggests that one can intervene to alter the genetic milieu in such a way as to extend the duration of an organism's natural life. One can easily predict that further elucidation of the specific genetic underpinnings of longevity will, inevitably, lead to such interventions in humans.

WORKPLACE ATTITUDES AND SMOKING CESSATION

A Harvard University study of the role of workplace attitudes towards smoking is reported in the American Journal of Health Promotion this month. The authors surveyed 11,456 employees, including 2,626 smokers, at 44 different worksites. The study assessed workplace social support for quitting tobacco.

Compared with so-called white-collar workers, blue-collar workers who smoked reported significantly less social pressure to quit smoking--as well as greater acceptance of smoking--by their peers at work. At the same time, smokers who strongly expressed an intention to quit smoking reported higher levels of social pressure against smoking at work as compared to smokers not planning to quit. The authors summarize that social attitudes towards smoking at work may play an important role in the decisions that smokers make to either continue smoking or to quit.

EFFECTS OF INADEQUATE SLEEP ON SURGEONS

From Denmark comes a study, reported in the British Medical Journal, that I can certainly relate to: the effects of inadequate sleep on surgeons' performance in the operating room. Fourteen surgery residents were assessed in a simulated operating room following a night of on-call activities in the hospital, with each resident reporting less than three hours of sleep during the preceding 24 hours (a very common occurrence among surgeons-in-training).

The sleep-deprived residents were required to perform standardized laparoscopic surgery tasks in a laparoscopic surgery simulator. The findings, not surprisingly, included an increase in time necessary to complete the tasks (as compared to the same residents' performance of these tasks when well-rested), and the commission of significantly more technical errors. The number of unnecessary movements also increased after a busy night in the hospital.

This is yet another study that demonstrates, contrary to traditional surgical training tenets, that sleep deprivation reduces the surgeon's accuracy and speed in the operating room.

Unfortunately, and more than most of the other clinical specialties, surgical training programs continue to submit their residents to a punishing schedule of hospital duty. Reports of surgical and non-surgical residents being involved in one-car automobile accidents at an alarmingly high rate, as well as other signs of exhaustion, are relatively common. Errors in patient treatment, by both surgeons and non-surgeon physicians, have been well documented to be associated with long periods of sleeplessness.

Despite the efforts of some states (New York, most notably) to limit the hours of resident physicians, little progress has been made in trimming the 80-100 hour work-weeks of most physicians-in-training. Despite the bravado and machismo of young surgeons-in-training, a chronic lack of sleep combined with a high-stress environment can lead to poor judgment, mistakes in the operating room, and sometimes even worse outcomes.

JWR contributor Dr. Robert A. Wascher is a senior research fellow in molecular & surgical oncology at the John Wayne Cancer Institute in Santa Monica, CA. Comment by clicking here.

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© 2002, Dr. Robert A. Wascher