High school pupils should prepare not only their brains but also their bodies for matriculation exams. Maccabi Health Services clinical dietitians Dr. Nestor Lipovtzky and Nira Feldman recommending eating five servings of vegetables and three servings of fruits in the days before a test. Minimize consumption of fat, sweets and other junk food. Try to eat three main meals and two healthful small meals a day. Exercise will also help, they advise. To improve your concentration during an exam, two hours before each, take one or two servings of complex carbohydrates plus protein, such as wholewheat bread with cheese or tuna, or a dish of chicken with rice, or unsweetened whole cereal with milk. Complex carbohydrates take longer to digest and give a feeling of satiety. They also encourage the release of serotonin - a neurotransmitter that gives people a good feeling. Just before the exam, eat fruit such as an apple or a cup of grapes or cherries, but not a calorie-ridden fatty snack. If you feel you just have to eat something sweet, however, choose an energy bar or one or two squares of chocolate. Make sure you drink a lot of cold water - and not a sugary beverage - before the exam, and bring a bottle for consumption during the test. If you don't like water, some natural orange juice or apple juice diluted with water is a good choice (but make sure you go to the bathroom before the test). US MAN GETS THIRD-HAND HEART The shortage of transplant organs has led to the death of many people around the world. But now a 45-year-old civil engineer named Mike Iwuchukwu has gotten a second chance at life with a third-hand heart. In his recent operation at Cedars-Sinai Medical Center in Los Angeles, he apparently became the first patient ever to receive a heart that had been transplanted once already. The reuse of any solid organ for transplantation is extremely rare and has been successfully accomplished only in the past few years. Members of Cedars-Sinai's heart transplant program said it is unusual to accept a previously transplanted heart, for several reasons, and the decision was made only after carefully considering all the information about the donor and recipient. In this case, the first recipient experienced non-heart-related complications during the transplant operation. Declared brain dead, the recipient became a potential donor and, with the family's consent, the heart was offered for donation six days later. OneLegacy, the transplant donor network serving seven Southern California counties, notified Cedars-Sinai's transplant specialists of the heart's availability. Few previously transplanted hearts become available to a second patient because most recipients go on to lead a relatively long life. If a once-transplanted heart is offered, several issues require careful deliberation, according to the transplant specialists. The heart already has been exposed to the tissue and antibodies of two people, which increases rejection risk and requires extra vigilance on the part of cardiologists and specialists in immunology. Also, because the heart's vessels have already been grafted once, a second procedure is more complex and potentially time-intensive. In addition, the heart muscle itself may be stressed from lack of oxygen and the inherent trauma of two operations. Iwuchukwu had a very rare heart condition called noncompaction syndrome, which gives the heart a sponge-like appearance. The disorder led eventually to the malfunction of his heart and the need for a transplant. A few months after the surgery, he says he feels strong and healthy, and was not worried when he learned that the heart had been transplanted before. He returns to Cedars-Sinai every week for testing, and there is no sign of rejection or any other complication. TEMPORARY SURGERY TATTOO The private Assuta Medical Centers (owned by Maccabi Health Services), which perform a lot of surgery, now use a temporary skin tattoo to mark the place of the organ to be operated on, just to make sure that their surgeons don't make the error of opening up the wrong side. Legs, arms, breasts, ovaries, lungs, kidneys and other organs and limbs can be marked. Statistics around the world show that for every 30,000 operations, one is mistakenly performed on the wrong organ or limb. The tattoo, which says "Operate Here) in blue, remains visible for about a week. It is better than stickers that can fall off or be moved. The idea was initiated by Dr. Arik Cahana, deputy director of Assuta Tel Aviv and head of the medical centers' risk management unit. The tattoo is applied a few days before the operation, when the patient comes for an explanation of the surgery. SEX AND ORAL CANCER The human papillomavirus is known to cause cervical cancer. Now researchers at the Johns Hopkins Kimmel Cancer Center have conclusive evidence that oral sex by a partner with HPV can cause some throat cancers in both men and women. Reporting in the New England Journal of Medicine, the researchers found that oral HPV infection is the strongest risk factor for the disease, regardless of tobacco and alcohol use, and having multiple oral sex partners tops the list of sex practices that boost risk for the HPV-linked cancer. The researchers stressed that oropharyngeal cancer is relatively uncommon, and the overwhelming majority of people with an oral HPV infection probably will not get throat cancer. Consistent condom use may reduce risk. Nevertheless, the risk exists. Their study of 100 men and women newly diagnosed with oropharyngeal cancer (located in the tonsils, back of the tongue, and throat), showed that those who had evidence of prior HPV infection were 32 times more likely to develop the cancer. This was much higher than the rate increase of threefold for smokers and twofold for drinkers. Study participants who reported having more than six oral sex partners in their lifetime were 8.6 times more likely to develop the HPV-linked cancer. Most HPV infections clear with few symptoms, but a small percentage of men and women who acquire cancer-causing or high-risk strains, such as HPV 16, may develop a cancer. A new vaccine called Gardisil, recently approved by the US Food and Drug Administration, can prevent genital HPV infection in girls and young women, but has not yet been shown to prevent infection in boys and men. The vaccine's ability to prevent oral HPV infection and oral cancers, which are more common in men, also is not known.