Snippets From Science

• Everyone’s DNA contains genes that can give rise to cancer. Fortunately, there are “tumor-suppressor” genes, some of which code for chemicals that block expression of genes that otherwise might induce a cell to begin to divide in an uncontrolled fashion. In the past, drugs for cancer treatment were often used one after the other, in the belief that “if this drug doesn’t work, we’ll try another.” A better understanding of the genetics of cancer cells is leading to treatments that can arrest their spread, including simultaneous treatment with several drugs. Progress is being made in targeting drugs depending on the specific genetic makeup of a patient’s cancer cells. With new treatments, over 90 percent of men with prostate or testicular cancer live at least 10 years; 90 percent of melanoma patients are still alive after 10 years; and for breast cancer 82 percent survive at least 10 years following treatment. The current emphasis is on controlling cancer, and future “cures” will likely depend on new findings about the genetics of cancer. It’s encouraging that at the moment there are 200 new drugs being tested for their ability to target and suppress certain cancer-causing mutations in cells. (Begley, S., Curing Cancer, Newsweek, Sept. 13, 2010)

• “More than one in four Americans suffers from a diagnosable psychiatric disorder at any given time, according to the National Institute of Mental Health. Sadly, about two-thirds of our behavioral and emotional problems are never diagnosed or treated.” This does not include soldiers returning from Iraq and/or Afghanistan. Statistics indicate that 30 percent of these soldiers have or will have serious psychological problems. The implications of this many people in our society with undiagnosed and untreated psychiatric problems are great. The good news: most of these problems are treatable. (Scientific American Mind, March/April 2010)

• Larger mammals tend to have slower heart rates. The average heart rate of a hamster is 450 beats a minute; cats and dogs, 120 beats/minute; humans, 72 beats/minute; elephants, 35 beats/minute; and whales, 8-10 beats/minute. Non-mammals have variable heart rates, with ranges from 6-12 beats/minute in turtles to hummingbirds, with rates of 250 when resting to 1,200 beats when feeding. (Mead and Gold, 2002, “Whales and Dolphins In Question,” The Smithsonian Answer Book, Smithsonian Press; other sources on animal heart rates)

• Most of us have heard of Parkinson’s Disease, but few of us know that 4 – 5 percent of Americans suffer from a condition known as “Essential Tremor.” In Parkinson’s Disease, the tremor occurs when the person is at rest, but diminishes when he or she tries to pick up an object. In essential tremor the opposite occurs. The tremor is absent when the person is at rest, but the hand begins to shake when reaching for an object, giving rise to another name: “intention tremor.” Evidence suggests that essential (intention) tremor may occur when neurons are lost in the cerebellum, a part of the brain involved in programming repetitive movement. An understanding of factors that enhance shaking, and the availability of a few drugs, provide hope for people with essential tremor. (Brain in the News, January, 2010)

Author’s note: this kind of tremor doesn’t mean the person is incapacitated. I knew three people with essential tremor: a fine dentist, a biologist who could remove the nucleus of a frog embryo using a micro-needle, and an entomologist who learned to pin small insects with ease. The coping trick: bracing the hand and timing the use of the dental drill, micro-needle, or pin to coincide with a given tremor movement.