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14 January 2010

Less sleep for kids may mean higher blood sugar

NEW YORK (Reuters Health) - Young children may be more apt to have high blood sugar, a precursor to diabetes, if they average 8 hours or less of sleep a night, report Chinese and American researchers.

This risk may be even greater among obese youngsters, Dr. Zhijie Yu, at the Chinese Academy of Sciences in Shanghai and colleagues note in Archives of Pediatric and Adolescent Medicine.

Moreover, Yu said in an email to Reuters Health, shorter sleep seemed to influence blood sugar "independently of a large variety of risk factors," such as age, gender, birth-related influences, early life feeding or later diet, recent illness, physical activity, body mass, and waist girth.

Yu's team investigated sleep duration and blood sugar levels in 619 obese and 617 non-obese children who were 3 to 6 years old and free of diabetes or blood sugar problems.

Parental reports showed a greater percentage of the obese (47 percent) than the non-obese (37 percent) kids averaged 8 or fewer hours of sleep nightly. These reports also showed nightly averages of 9 or 10, or 11-plus, hours of sleep less common in obese (37 and 16 percent) versus non-obese (43 and 20 percent) kids, respectively.

High blood sugar levels, defined as 100 milligrams of glucose per deciliter of blood after not eating for 8 hours, appeared about 1.35-fold and 2.15-fold more likely in the shorter-sleeping non-obese and obese kids, respectively. (For comparison, 110 milligrams per deciliter is considered "pre-diabetes," while diabetes is diagnosed at 126 milligrams.)

High blood sugar levels were evident in 23 of the 217 non-obese and in 49 of the 291 obese kids sleeping less than 8 hours. By contrast, 21 each of the 175 non-obese and 229 obese kids getting 9 or 10 hours of sleep nightly had high blood sugar.

Overall, 11 of the children had levels above 126 milligrams per deciliter, the level at which diabetes is diagnosed.

These findings hint that, similar to adults, adequate sleep may help kids, "maintain a healthy body weight and an optimal (blood sugar) level," Yu said.

However, Yu's team highlights the need for further studies to confirm these findings in both Chinese and other populations of youngsters.

SOURCE: Archives of Pediatric and Adolescent Medicine, January 2010

Organic coffee: Why Latin America's farmers are abandoning it

Latin America produces an estimated 75 percent of the world's organic coffee. But the economic benefits many small farmers were promised if they converted to organic haven't materialized.

This is very high quality and it’s organic. But ... the roasters don’t want to pay extra these days,” says the manager of FEDECOCAGUA, Guatemala’s largest growers’ cooperative, which represents 20,000 farmers.

Mr. De Leon is asking $2 per pound for the green (unroasted) coffee, about 50 cents more than the going price. But he says he’ll soon have to sell it as conventionally grown coffee, which sells for less.

That’s why many Mesoamerican farmers here are starting to give up on organic coffee: The premium price that it used to fetch is disappearing.

From Mexico to Costa Rica, at least 10 percent of growers have defected in the past three years, estimates the Center for Tropical Agricultural Research and Higher Education in Costa Rica (CATIE). Researchers say that each year, about 75 percent of the world’s organic coffee comes from Latin America.

Farmers have returned to the chemical fertilizers and pesticides that increase production, albeit at a cost to the environment. Although organic still pays a premium of as much as 25 percent over conventional coffee, it’s not enough to cover the added cost of production and make up for the smaller yields. For consumers, the defections threaten to make the coffee harder to find.

“This is a critical point for organic coffee. It was starting to make the conversion to the mainstream,” says Jeremy Haggar, who oversees the research for CATIE. If farmers continue to abandon organic coffee, “prices will definitely go up and it will return to being a niche product.”

'Promised economic benefits'
Under specialty “green” labels at places like Wal-Mart and McDonald’s, organic beans and brews have become cheaper and more widely available recently. Last year, North American sales reached a record $1.3 billion, a 13 percent increase from 2007.

Major retailers already struggle to fill demand. Seattle-based Starbucks Corp., the world’s largest coffeehouse company, said just 3 percent of its coffee purchases, about 10 million pounds, were organic last year.

“Our purchases of certified organic coffee are limited due to the limited quantities available worldwide and the constraints of the organic certification system for farmers,” the company said in a statement issued in response to questions.
“I can sell [nonorganic coffee] to a coyote [middle man] for around the same price [as organic], a little less, and I can use whatever I want on the coffee plants – fertilizers I can buy, pesticides,” says Jose Perez, who stopped growing organic coffee on his three-acre farm in Guatemala last year. “I can grow a lot more this way.”

Mr. Perez is an example of what World Bank coffee researcher Daniele Giovannucci says was an empty promise made to growers. “Many farmers ... were promised economic benefits by those that wanted them to convert, which was a very bad idea,” he writes in an e-mail, “and [this trend] is bearing the fruit in their dissatisfaction.”

Organic demanded, but not at higher price
A decade ago, with coffee prices bottoming out and at the urging of some development organizations, tens of thousands of Latin American farmers began to convert their fields to producers of certified organic products. To do so, farmers followed strict rules set by a handful of agencies, including the US Department of Agriculture, that require soil be free of pesticides and chemical fertilizers for three years.

After making the conversion, they would be supplying a growing market that paid as much as 40 percent more. They would also be preserving their land. Conventional farms apply as much as 250 pounds of chemical fertilizers on every acre. “And they use tons of pesticides that are harmful to human health and affect biodiversity,” Haggar says. Organic farms, rich with flora, trap more carbon than their conventional counterparts, an important benefit for a crop threatened by climate change.

However, the farmers don’t receive the financial benefits of organic coffee until they are certified, meaning they were expected to absorb extra costs for three years. Many went into debt. Now, they are quitting organic farming.

“When you’re a small organization like ours, it’s already difficult to survive against the big growers. So when you lose members, it hurts you a lot,” says Marvin Lopez, manager of APODIP, a Coban, Guatemala-based cooperative of organic growers that lost half of its members, about 380, last year.

“I get calls every day from buyers in the US who are asking me if I have any organic [coffee] available. But then I tell them the price, $2 per pound,” De Leon says, pointing to an e-mail with an offer to pay $1.50 per pound. “So, the coffee just sits there.”

Blueberries may boost memory in older adults: Study

Supplemental blueberries for only 12 weeks may boost memory in older people with early memory problems, says a new study from the US.

A daily drink of about 500 mL of blueberry juice was associated with improved learning and word list recall, as well as a suggestion of reduced depressive symptoms, according to findings published in the Journal of Agricultural and Food Chemistry.

The study is said to be the first human trial to assess the potential benefits of blueberries on brain function in older adults with increased risk for dementia and Alzheimer’s.

Alzheimer's disease is the most common form of dementia and currently affects over 13 million people worldwide. The direct and indirect cost of Alzheimer care is over $100bn (€ 81bn) in the US alone. The direct cost of Alzheimer care in the UK was estimated at £15bn (€ 22bn).

“These preliminary memory findings are encouraging and suggest that consistent supplementation with blueberries may offer an approach to forestall or mitigate neurodegeneration,” wrote the researchers, led by Robert Krikorian from the University of Cincinnati Academic Health Center.

“Interpretation of our findings should be tempered because of the relatively small sample size and the absence of a blueberry-specific control, although comparison with the analogous placebo beverage data provides some assurance that the observed changes in memory performance were not attributable to practice effects,” they added.

Berries are booming

Blueberry consumption has previously been linked to reduced risk of Alzheimer’s, with reports in 2003 leading to a boom in sales in the UK, going from £10.3m (€14.9m) in 2003 to almost £40m (€58m) in 2005, according to UK supplier BerryWorld.

The beneficial effects of the blueberries are thought to be linked to their flavonoid content - in particular anthocyanins and flavanols. The exact way in which flavonoids affect the brain are unknown, but they have previously been shown to cross the blood brain barrier after dietary intake.

It is believed that they may exert their effects on learning and memory by enhancing existing neuronal connections, improving cellular communications and stimulating neuronal regeneration.

Study details

Krikorian and his co-workers recruited nine older people with an average age of 76.2 and an average educational level of 15.6 years. Subjects were assigned to receive a daily dose of blueberry juice equivalent to between 6 and 9 mL per kilogram of body weight per day. The juice used in the study was provided by the Wild Blueberry Association of North America.

Results showed significant improvements in improved learning and word list recall. There was also a trend towards reduced depressive symptoms and lower glucose levels. Krikorian and his co-workers added that it would be interesting in future studies to examine if changes in cognitive function are associated with metabolic improvements.

“Replication of the findings in a larger, controlled trial will be important to corroborate and amplify these data,” wrote the researchers. “On balance, this initial study establishes a basis for further human research of blueberry supplementation as a preventive intervention with respect to cognitive aging,” they concluded.

The other researchers were affiliated with Agriculture and Agri-Food Canada and the USDA Human Nutrition Research Center on Aging and Tufts University.

Source: Journal of Agricultural and Food Chemistry
Published online ahead of print, doi: 10.1021/jf9029332
“Blueberry Supplementation Improves Memory in Older Adults”
Authors: R. Krikorian, M.D. Shidler, T.A. Nash, W. Kalt, M.R. Vinqvist-Tymchuk, B. Shukitt-Hale, J.A. Joseph

12 January 2010

48% of Fast Food Soda Fountains Contain Bacteria that Grew in Feces

Seems like the reasons to not eat at fast food restaurants just keep on piling up. We've heard all about the unseemly practices that go into obtaining their meats and innumerable other horrors. But now, let's look at the quality of the soda fountains--another staple of the fast food experience. A recent study has revealed that a full 48% of soda fountains at fast food restaurants contain coliform bacteria--a bacteria that commonly grows in feces. Oh, and 11% contained E. Coli, too.

The study was done by a team of microbiologists at Hollins University, and the findings were just published in the International Journal of Food Microbiology

Coliform bacteria was detected in 48% of the beverages and 20% had a heterotrophic plate count greater than 500 cfu/ml. [...] More than 11% of the beverages analyzed contained Escherichia coli [E. Coli] and over 17% contained Chryseobacterium meningosepticum. Other opportunistic pathogenic microorganisms isolated from the beverages included species of Klebsiella, Staphylococcus, Stenotrophomonas, Candida, and Serratia. Most of the identified bacteria showed resistance to one or more of the 11 antibiotics tested.
That's right--not only do soda fountains contain bacteria that originated in poop and potentially dangerous amounts of E. Coli, but they've become resistant to antibiotics as well. Fantastic.

Journalist Tom Lawskawy, who broke news of the study, points out, however, that the researchers say there's only been one certified outbreak over in the last ten years. And to be clear, coliform bacteria does not only grow in feces, though it commonly does--and the majority of coliform bacteria are not dangerous. But Lawskawy also notes that there's an "awful lot of 'gastric distress' that goes unreported."

Which is undeniably true--how many times can you remember having a meal at a fast food restaurant and inexplicably not feeling so hot afterward? Perhaps our friend the coliform bacteria--you know, the one that grows in feces and that you have something like a 50% chance of ingesting if you drink from fast food soda fountains--has played a part.

Gross.

Can Fecal Bacteria in Soda Really Make You Sick?
Now, while the whole concept does indeed seem disgusting, it's useful to remember that there is a small amount of coliform bacteria in much of the stuff we drink--it's legal, and safe, in certain percentages in US drinking water. And there's only one strain of E. Coli (O157:H7) that's dangerous, which is why outbreaks attributed to soda fountains are so extremely rare--and why nobody really needs to fear for their lives when going for a refill of Dr. Pepper.

That said, there are still people getting needlessly sick to their stomachs by the poor cleaning practices of fast food joints. As the scientists conclude in their abstract:

These findings suggest that soda fountain machines may harbor persistent communities of potentially pathogenic microorganisms which may contribute to episodic gastric distress in the general population and could pose a more significant health risk to immunocompromised individuals. These findings have important public health implications and signal the need for regulations enforcing hygienic practices associated with these beverage dispensers.

Pomegranate may fight some breast cancers

Laboratory tests suggest pomegranates contain chemicals that reduce the risk that women will develop hormone-dependent breast cancers, researchers report.
The key seems to be a phytochemical, ellagic acid, found in pomegranates. It inhibits aromatase, an enzyme linked to the development of estrogen-responsive breast cancer.

"We were surprised by our findings," principal investigator Shiuan Chen, co-leader of the Breast Cancer Research Program at City of Hope in Duarte, Calif., said in a news release. "We previously found other fruits, such as grapes, to be capable of the inhibition of aromatase. But, phytochemicals in pomegranates and in grapes are different."

More studies are needed, Gary Stoner, a professor in the department of internal medicine at Ohio State University, said in the same news release. "It's not clear that these levels could be achieved in animals or in humans" because the chemicals may not be easily absorbed from food.

Still, he said, people "might consider consuming more pomegranates to protect against cancer development in the breast and perhaps in other tissues and organs."


Vitamins and minerals may slash bladder cancer risk

Increased intakes of vitamin E may reduce the risk of bladder cancer by about 35 per cent, says a new study from an international team of researchers

Findings published in Cancer Causes and Control also showed that carotenoids, niacin, thiamine, and vitamin D may reduce the risk of bladder cancer in older people.

“The effects of vitamin E, carotenoids, vitamin D, thiamin, and niacin in relation to the risk of developing bladder cancer may warrant further investigation,” report the researchers, led by Maree Brinkman from The Cancer Council Victoria in Australia.

“Future studies should focus on optimal doses and combinations of these micronutrients particularly for high risk groups such as heavy smokers and older individuals,” they state.

Bladder cancer is diagnosed in about 336,000 people every year worldwide, and it is three times more likely to affect men than women, according to the European School of Oncology.

Study details

Brinkman and her co-workers analysed dietary data from 322 people with bladder cancer and 239 healthy controls. A 121-item food frequency questionnaire was used to estimate dietary intakes.

Results showed that, in general, people with the highest average intakes of vitamin E (at least 193.4 milligrams per day) were 34 per cent less likely to develop bladder cancer. The highest average intakes of phosphorous (1,557 milligrams) were associated with a 51 per cent reduction in bladder cancer risk.

“Although we observed an approximate 50 per cent reduction in the odds of bladder cancer associated with higher dietary intake of phosphorus, it was not statistically significant,” wrote the researchers. “Given this ubiquitous micronutrient is an important physiological component of DNA, RNA, ATP, and cell membranes, it may be worthy of further consideration.”



When the researchers focused their analysis on smokers, they found that the highest intakes of vitamin E, carotenoids (18 milligrams), and niacin (46.5 milligrams), were associated with a 42, 38, and 34 per cent reduction in bladder cancer risk in heavy smokers.

In older individuals, the highest average intakes of carotenoids, vitamin D (641 International Units), thiamin (3.35 milligrams), niacin, and vitamin E were all associated with a reduced bladder cancer risk.

“Bladder cancer is a disease that typically affects older people, and bioavailability of B-group vitamins may be compromised in this demographic by certain drugs (e.g., acid lowering agents),” stated the researchers. “Additionally, vitamin E, like carotenoids acts as an antioxidant and, as suggested by our results, could be more beneficial under conditions of the greatest oxidative stress such as smoking and ageing.”

The researchers called for additional study to further examine these potentially protective relationships.

The study was supported by the National Institute of Environmental Health Sciences and the National Cancer Institute at the US National Institutes of Health (NIH).

Review supports omega-3 for liver health

Increased intakes of omega-3 fatty acids from marine sources may benefit people with non-alcoholic fatty liver disease (NAFLD), says a new review of the literature.

A review of four human studies found that the fatty acids could improve liver health and function, and increase insulin sensitivity in people suffering from fatty liver, a condition that is usually symptomless but said to increase the risk for liver inflammation, and ultimately results in liver failure.

Fatty liver is reportedly on the rise in the US, with between one quarter and one half of Americans, and the prevalence if nonalcoholic fatty liver disease (NAFLD) has increased in line with the ongoing obesity epidemic.

Led by Dr Gail Masterton from the Royal Infirmary of Edinburgh in Scotland, the reviewers report their findings in the journal Alimentary Pharmacology & Therapeutics.

Previous studies have implicated omega-3 in protective benefits against obesity-related conditions. A considerable number of studies already support the benefits of the omega-3 fatty acids eicosapentaenoic acid (EPA, C20:5 n-3) and docosahexaenoic acid (DHA, C22:6 n-3) for cardiovascular health, and cognitive health. Other areas of potential for the fatty acids include mood and behaviour, eye health, cancer risk reduction, and improved infant development.

It is biologically plausible that omega-3 fatty acids may improve liver health, said the reviewers because “they have several potential mechanisms of action, the most important being to alter hepatic gene expression, thereby switching intracellular metabolism from lipogenesis and storage to fatty acid oxidation and catabolism.

“There is also evidence that they improve insulin sensitivity, are anti-inflammatory and reduce TNF levels so offering several potential therapeutic mechanisms,” they added.

“To date the trials have all been open label and none have employed a prospective, randomised, blinded, placebo controlled, adequately powered trial methodology to submit these promising preliminary findings to proper scientific rigour,” wrote Masterton and her co-workers. “Such studies are now urgently required,” they added.

11 January 2010

The Hidden Benefits of Exercise

As millions of Americans flock to the gym armed with New Year's resolutions to get in shape, medical experts are offering an additional reason to exercise: Regular workouts may help fight off colds and flu, reduce the risk of certain cancers and chronic diseases and slow the process of aging.

Physical activity has long been known to bestow such benefits as helping to maintain a healthy weight and reduce stress, not to mention tightening those abs. Now, a growing body of research is showing that regular exercise—as simple as a brisk 30- to 45-minute walk five times a week—can boost the body's immune system, increasing the circulation of natural killer cells that fight off viruses and bacteria. And exercise has been shown to improve the body's response to the influenza vaccine, making it more effective at keeping the virus at bay.

"No pill or nutritional supplement has the power of near-daily moderate activity in lowering the number of sick days people take," says David Nieman, director of Appalachian State University's Human Performance Lab in Kannapolis, N.C. Dr. Nieman has conducted several randomized controlled studies showing that people who walked briskly for 45 minutes, five days a week over 12 to 15 weeks had fewer and less severe upper respiratory tract infections, such as colds and flu. These subjects reduced their number of sick days 25% to 50% compared with sedentary control subjects, he says.

Medical experts say inactivity poses as great a health risk as smoking, contributing to heart disease, diabetes, hypertension, cancer, depression, arthritis and osteoporosis. The Centers for Disease Control and Prevention says 36% of U.S. adults didn't engage in any leisure-time physical activity in 2008.

Even lean men and women who are inactive are at higher risk of death and disease. So while reducing obesity is an important goal, "the better message would be to get everyone to walk 30 minutes a day" says Robert Sallis, co-director of sports medicine at Fontana Medical Center, a Southern California facility owned by managed-care giant Kaiser Permanente. "We need to refocus the national message on physical activity, which can have a bigger impact on health than losing weight."

Regular exercise has been shown to combat the ongoing damage done to cells, tissues and organs that underlies many chronic conditions. Indeed, studies have found exercise can lower blood pressure, reduce bad cholesterol, and cut the incidence of Type 2 diabetes.

Building on that earlier research, scientific studies are now suggesting that exercise-induced changes in the body's immune system may protect against some forms of cancer. For example, Harvard Medical School's consumer Web site (hms.harvard.edu/public/consumer) notes that more than 60 studies in recent years taken together suggest that women who exercise regularly can expect a 20% to 30% reduction in the chance of getting breast cancer compared with women who didn't exercise. While researchers are still studying the molecular changes caused by exercise and how they affect cancer, the studies suggest the outcome could be due to exercise's ability to lower estrogen levels.

One study of 3,000 women being treated for breast cancer, published in the Journal of the American Medical Association, showed that for those patients with hormone-responsive tumors, walking the equivalent of three to five hours per week at an average pace reduced the risk of dying from the disease by 50% compared with more sedentary women.

Researchers are also investigating whether exercise can influence aging in the body. In particular, they are looking at whether exercise lengthens telomeres, the strands of DNA at the tips of chromosomes. When telomeres get too short, cells no longer can divide and they become inactive, a process associated with aging, cancer and a higher risk of death.

In a study published in November in Circulation, the medical journal of the American Heart Association, German researchers compared two groups of professional athletes (32 of whom were in their early 20s, and 25 who were middle-aged) with two groups (26 young and 21 middle-aged) who were healthy nonsmokers, but not regular exercisers. The athletes had significantly less erosion in telomeres than their more sedentary counterparts. The study concluded that physical activity has an anti-aging effect at the cellular level, suggesting exercise could prevent aging of the cardiovascular system.

Efforts are underway to get sedentary Americans moving. The federal government issued its first national exercise guidelines in 2008. Now it is working with a number of medical and fitness groups to develop a National Physical Activity plan, to be released early this year, to encourage Americans to adhere to the guidelines.

The guidelines, developed by the Department of Health and Human Services and available at health.gov/paguidelines, recommend that adults get at least two hours and 30 minutes weekly of moderate-intensity aerobic physical activity, or one hour and 15 minutes a week of vigorous-intensity aerobic exercise, or an equivalent combination of both. The guidelines also say that additional health benefits can be had from as much as doubling the minimum recommendation for aerobic exercise. Also recommended: muscle-strengthening activities two or more days a week, which protects against a decline in bone mass, especially that experienced by post-menopausal women.

Kaiser Permanente's Dr. Sallis also is chairman of Exercise is Medicine, a two-year-old program developed by the American College of Sports Medicine and the American Medical Association to encourage doctors to assess and review each patient's physical activity program at every visit. A survey by the ACSM, whose members include physicians and exercise-science professionals, found that only four out of 10 doctors talk to their patients about the importance of exercise, and they don't always offer suggestions on the best ways to be physically active.

Kaiser Permanente's California facilities last year began rolling out exercise counseling to eight million members as part of their regular doctor visits. The company also has set up a toll-free phone line to help members create a personal-fitness plan incorporating favorite activities like gardening. "Exercise can be used like a vaccine to prevent disease and a medication to treat disease," says Dr. Sallis. "If there were a drug with the same benefits as exercise, it would instantly be the standard of care."

While some patients may have risk factors such as heart conditions that could lead to heart attacks and sudden cardiac death with physical exertion, physicians can screen for such risks before prescribing an exercise program. Also, the exerciseismedicine.org Web site includes videos and self-assessment tools for consumers on how to start an exercise program, including how to exercise with diseases such as asthma and heart disease, and exercise following a stroke or heart attack.

Starting an exercise program can have benefits at any age, but is particularly important for those over 40, when physical strength, endurance, flexibility and balance begin to decline, says Pamela Peeke, a Bethesda, Md., physician and fitness expert who is the author of "Fit to Live," an advice book on how to create and stick to a fitness plan.

Naomi Henderson, 66, says Dr. Peeke gave her an exercise prescription several years ago, when she weighed 220 pounds. The plan called for Ms. Henderson, who owns her own market-research company, to start by walking on a treadmill five minutes a day and gradually increase the duration as her fitness level improved. Eventually she was able to walk in a marathon. Ms. Henderson says she has slimmed down to a size 12 from an 18 and says she is rarely ill. "I look at exercise as no different than a drug I have to take to stay healthy," she says.

Lisa Callahan, co-director of the Women's Sports Medicine Center at New York's Hospital for Special Surgery, says her patients are often only partially aware of the benefits of exercise.

They may know that it is helpful in reducing their risk of osteoporosis, for example, but they usually don't know that a combination of strength training, aerobic exercise and balance training is most effective at staving off the disease, says Dr. Callahan, author of "The Fitness Factor," a guide for women.

Dr. Nieman, of Appalachian State University, says that during exercise, two types of immune cells circulate more freely in the blood, neutralizing pathogens. Although the immune system returns to normal within three hours, the effect of the exercise is cumulative, adding up over time to reduce illness rates, he says. He compares the process to "a cleaner who comes in for an hour a day, so by the end of a month, your house looks much better."

But, Dr. Nieman says, high-intensity exercise over long periods, like running a marathon, can "take a good thing too far." Such exertion can induce the release of stress hormones in the body that damp some functions of the immune system temporarily, increasing susceptibility to infection for short periods. He cites a five-year study he conducted on 350 athletes who completed an ultra-marathon 160-kilometer race in the Sierra Nevada mountains. Among the contestants, one out of four reported sickness in the two weeks following the races.

Still, says Robert Mazzeo, a professor in the department of integrative physiology at the University of Colorado in Boulder, although a single bout of intense exercise can suppress the immune system, long-term training in marathoners and other athletes can boost their baseline immunity and ability to respond to the stress of intense exercising. Rather than worrying about super athletes, however, "my concern is the sedentary people who start out pumping the Stairmaster too hard, then get sick and stop working out," says Dr. Mazzeo. "If you've made a New Year's resolution to get in shape, don't try to do it all at once," he says.

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