What's Hot Archive
August 31, 2005
Statins given after heart attack cut deaths by half
A study published in the September 1 2005 issue in the American Journal of Cardiology (http://www.sciencedirect.com/
science/journal/00029149) has found that treating patients with a statin drug within twenty-four hours of a heart attack reduces deaths from the event by more than 50 percent compared to those not treated with the drugs. The investigation is the largest clinical study of its kind to date.
Researchers at the University of California Los Angeles evaluated data from the National Registry of Mycocardial Infarction 4 for 300,823 patients admitted to a hospital due to heart attack. They discovered that administering a statin drug within 24 hours to patients who had been taking the drugs lowered in-hospital mortality by 54 percent compared to patients who were not given statins. Among those who had not previously been using statins, receiving the drug lowered the risk of death by 58 percent. And in those patients for whom statin use was discontinued following their heart attack admissions, there was a slight increase in deaths. A reduction in cardiac arrest, cardiac shock, cardiac rupture and ventricular fibrillation was also found among patients who received the drugs.
Statins apparently provide their benefit by increasing nitric oxide in the cardiovascular system which reduces inflammation. Lead author Dr. Gregg C. Fonarow, who is the Eliot Corday Chair in Cardiovascular Medicine and Science and professor of cardiology at the David Geffen School of Medicine at UCLA stated, "We were surprised that early statin therapy showed such a striking effect immediately after a heart attack. We also found that statins provided additional protection from other heart attack complications as well. As statins are already routinely started in myocardial infarction patients prior to hospital discharge, it would be relatively easy to administer this medication on arrival to the emergency department."
August 29, 2005
Inflammation involved in artery stiffness
Chronic inflammation has been indentified as a factor in a growing number of diseases and conditions. Now researchers at the Mayo Clinic report in the August issue of the American Journal of Hypertension, (http://www.sciencedirect.com/
science/journal/08957061) that low grade inflammation as indicated by increased levels of C-reactive protein (CRP, a marker of inflammation) is associated with arterial hardening or stiffening. Loss of arterial elasticity is can increase the risk of heart attack, congestive heart failure, and stroke, and increased levels of CRP have been associated with these conditions, however some scientists question whether elevations in CRP actually affect the blood vessels and do not just act as a marker for the presence of these diseases.
In collaboration with researchers from the University of Michigan, the Mayo Clinic team enrolled 214 men and women with an average age of 59 who did not have a history of stroke or heart attack. They measured blood levels of C-reactive protein and assessed three indicators of arterial stiffness: aortic augmentation index, carotid-femoral pulse wave velocity and pulse pressure.
It was found that CRP levels were associated with all three measures of arterial stiffness. Lead researcher Iftikhar Kullo MD of the Mayo Clinic's Department of Internal Medicine Division of Cardiovascular Diseases commented, "The current inability to accurately predict cardiovascular events such as heart attack is a problem, and anything we can do to improve risk assessment is a public health priority. Our study provides a new insight into how low grade inflammation could be related to heart and stroke by its association with arterial stiffness. Thus suppression of inflammation may be a target of drug therapy to improve arterial health."
August 26, 2005
Zinc supplements may reduce death among children in developing countries
A study published early online on August 23 2005 in The Lancet http://www.thelancet.com/journals/lancet showed that giving children in developing countries a zinc supplement just once per week can significantly lower the risk of illness and mortality. Children in developing countries are at risk of death in early childhood due to the prevalence of infectious diseases such as pneumonia and diarrhea, and daily zinc supplements have been found in previous research to offer protection against these diseases and reduce mortality.
Abdullah Brooks of the International Centre for Diarrhoea Disease Research, in Dhaka, Bangladesh and colleagues enrolled 1,621 children between the ages of two months to one year who resided in in Kamalapur, Bangladesh. The team treated half of the children with 70 milligrams zinc in the form of a syrup to be administered orally once per week for a period of one year, while the remainder received a placebo.
They found that children who received zinc grew an average of .9 centimeters taller than the placebo group after ten months. The incidence of pneumonia, diarrhea and other illnesses were significantly reduced in the zinc group by the study's conclusion. While fourteen children who received the placebo died over the course of the study, there were only two deaths among those who received zinc. Ten of the deaths among children who received the placebo were due to pneumonia, yet there were no pneumonia-related deaths among those who received the zinc supplement.
The authors concluded, "Zinc substantially reduced the incidence of pneumonia and other upper and lower respiratory tract disease, and modestly reduced that of diarrhoea. However, the effect of zinc on mortality was strong . . . Zinc might be progressively protective against more invasive and severe disease, leading to an 85% reduction in overall mortality, primarily owing to pneumonia."
August 24, 2005
Butterbur as effective as antihistamines in allergic rhinitis
In the largest trial to date of its kind, Swiss and German researchers have found that an extract of the herb butterbur (Petasites hybridus) is as effective in intermittent allergic rhinitis (IAR) as fexofenadine, an antihistamine commonly used for the condition. Intermittent allergic rhinitis, also known as hay fever, affects up to 20 percent of individuals in Western countries, and can affect work performance and quality of life.
In a double-blind, parallel group trial, Andreas Schapowal and colleagues divided 330 allergy sufferers at eleven centers to receive butterbur tablets containing 8 milligrams total petasine three times daily, fexofenadine once daily, or a placebo. They found that both butterbur and fexofenadine both improved symptoms significantly compared to the placebo during both the day and evening/night. In addition, butterbur did not cause the drowsiness that is a common side effect with antihistamine drugs.
Butterbur inhibits the production of molecules called leukotrienes, which are involved in the inflammatory response to allergens. Butterbur extract can also stimulate prostaglandins that play a role in the reduction of inflammation. Dr Schapowal concluded, "Despite being a herbal drug, Butterbur Ze339 has now been subject to a series of well controlled trials and should be considered as an alternative treatment for IAR. Because Butterbur does not cause the sort of drowsiness that is so often associated with other antihistamines it could be particularly useful for patients who can not tolerate other therapies."
August 22, 2005
Half the women treated with osteoporosis drugs may have insufficient vitamin D levels
Research conducted by Michael F Holick, MD, PhD, of Boston University School of Medicine and colleagues has found that women being treated for osteoporosis have low levels of vitamin D, a nutrient that is necessary for adequate bone mineralization. The study was published in the June 2005 issue of the Journal of Clinical Endocrinology & Metabolism (http://jcem.endojournals.org/).
Dr Holick and colleagues recruited 1,536 women from 61 study sites who had been taking osteoporosis medications for a minimum of three months. Participants were allowed to have used vitamin D supplements, but were excluded if they had recently decreased or increased the amount taken. All participants received medical examinations during which they were questioned concerning medication and supplement intake, and blood samples were drawn and serum 25-hydroxyvitamin D (the active vitamin D metabolite) levels measured.
Fifty-two percent of the women were found to have inadequate levels of 25-hydroxyvitamin D, defined as less than 30 nanograms per milliliter. Eighteen percent had levels even lower, at 20 nanograms per milliliter or below. Sixty-three percent of women who reported an intake of 400 international units or less of supplemental vitamin D had inadequate vitamin D levels compared to 45 percent of those whose intake was 400 international units or greater. The absence of prior discussion with a physician concerning vitamin D's importance to bone health was also associated with lower levels of the vitamin.
The authors write that although the study was conducted during winter when vitamin D levels are usually lower, even with adequate sun exposure during summer and fall the public is still at risk for low levels of the vitamin because its half life is only two weeks. They recommend greater education concerning improving vitamin D status in women with osteoporosis.
August 19, 2005
Beta-cryptoxanthin protects against inflammatory polyarthritis
Researchers at England's University of Manchester's School of Medicine have found that men and women whose diets contain higher amounts of beta-cryptoxanthin as well as vitamin C have a lower risk of developing inflammatory polyarthritis (IP) , including rhematoid arthritis. Beta-cryptoxanthin is a carotenoid found in brightly colored fruits and vegetables such as oranges and carrots.
Working with researchers from the Institute of Public Health at the University of Cambridge, Dr Dorothy Pattison and her Manchester colleagues determined the intake of carotenoids from the diet diaries and the results of health questionnaires completed by over 25,000 participants in the European Prospective Investigation of Cancer Norolk study of diet and chronic disease. The subjects, who were between the ages of 45 and 74 upon enrollment, were followed for nine years during which 88 cases of inflammatory polyarthritis were diagnosed.
When participants with inflammatory polyarthritis were compared to 176 age and gender-matched control subjects, beta-cryptoxanthin and zeaxathin emerged as the carotenoids offering the greatest protection against the disease. Dr Pattison summarized the results: "We found that the average daily beta-cryptoxanthin intake of the 88 patients who had developed inflammatory polyarthritis was 40% lower than those who hadn't, and their intake of another carotenoid, zeaxanthin, was 20% lower. Those in the top third for beta-cryptoxanthin intake were only half as likely to develop IP as those in the lowest third, and vitamin C was also found to be an important factor."
Earlier research has indicated that the antioxidant activity of beta-cryptoxanthin and vitamin C are protective against oxidative damage in the body that leads to inflammatory conditions. The results of the current study confirm previous findings by Dr Pattison that associated low fruit and vegetable intake with an elevated risk of developing inflammatory polyarthritis.
August 17, 2005
Nutritional intervention aids in breast cancer patients’ recovery
A study funded by the National Cancer Institute, published in the July 1 2005 issue of the Journal of Clinical Oncology, found that younger breast cancer patients who received education concerning the disease or nutritional recommendations reported better quality of life following treatment than did women who received no interventions.
Michael Sheier, who is the director of Carnegie Mellon University’s department of psychology, and colleagues enrolled 252 early stage breast cancer patients aged 50 and younger two months after the women finished their treatments. "These are women who had gone through some combination of surgery, radiation and chemotherapy and then were told by their doctors 'OK, your treatment is over, it's time to try to go on with your life.' These women experience anxiety. They wonder about their cancer," Dr Sheier stated.
The women were divided into three groups who received educational sessions concerning breast cancer, information about consuming a healthy diet, or standard medical care. Participants were surveyed at the beginning of the study, and at four and nine months following the end of the interventions.
It was found that women who received the educational or nutritional intervention reported improved quality of life, including more optimism, less depression, and better physical functioning compared to the women who received neither intervention. Nutritional advice had the greatest benefit and effects were found to improve over time.
Dietary interventions such as those provided by the study are traditionally aimed at influencing the patients eating habits, however, this study found that the effects were more far-reaching. “This is the first time that a nutritional intervention has been explicitly used to enhance the patients' quality of life" Dr Scheier announced. A future study will determine if the benefits continue for an even longer period of time.
August 15, 2005
Grape seed extract elevates antioxidant enzymes, lowers lipid peroxidation in rat CNS
The August 5 2005 issue of Neuroscience Letters published the findings of researchers at the University of Madras in Chennai, India that administering grape seed extract to older rats had a rejuvenating effect on their central nervous system antioxidant system. Reactive oxygen species and reactive nitrogen species oxidize proteins, DNA and lipids in the brain, leading to cell death and such neurodegenerative disorders as Alzheimer's disease or Parkinson's disease. Higher levels of antioxidants in the brain help prevent some of this damage from occurring.
Chinakannu Panneerselvam and colleagues gave young and old male rats 100 milligrams per kilogram body weight grape seed extract per day . Young and old rats who did not receive the extract served as controls.
Upon examination of the spinal cord, cerebral cortex, striatum and hippocampus of the rats after 30 days, lipid peroxidation (a marker of oxidative stress) was found to be increased in the older rats compared to both younger groups. Among rats who received grape seed extract, lipid peroxidation was lower in every area than levels measured in their same-aged nonsupplemented counterparts, but this difference was only significant among the aged group. The antioxidants vitamin C, vitamin E and reduced glutathione, and antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase were lower all areas examined in the older groups than in the younger animals, and similarly, both young and old rats who received grape seed extract had higher levels of antioxidants in nearly every area examined than rats of the same age who did not receive the supplement, yet the difference was significant only in the older group.
The authors suggest that the ability of grape seed extract to reduce lipid peroxidation is due to the free radical scavenging property of flavonoids contained in the extract.
August 12, 2005
Can prostate cancer be reversed by lifestyle changes?
A report published in the September 2005 issue of the Journal of Urology (www.jurology.com) showed that changes in diet and lifestyle reduced a marker of prostate cancer (prostate specific antigen, or PSA) in men with biopsy-confirmed disease. The study is the first randomized controlled trial to demonstrate that lifestyle changes affect any type of cancer progression.
For the current study, Dean Ornish, MD, who is a clinical professor at the University of California, San Francisco, and colleagues enrolled 93 men with prostate cancer who had chosen not to be treated by conventional methods. The men were divided into two groups, one of which was advised to adopt a diet consisting of plant based foods supplemented with soy, vitamins and minerals, while the second group was not advised to make any dietary modifications. The first group also participated in a moderate exercise program and a weekly group support session.
Following a year on the program, PSA levels were reduced in the lifestyle modified group, while they increased in the comparison group, necessitating treatment in some cases. When serum from both groups was administered to prostate tumor lines, that of the improved lifestyle group inhibited tumor growth by 70 percent, compared to 9 percent in the control group. Degree of lifestyle change was found to be negatively correlated with PSA levels and positively correlated with the ability to inhibit tumor growth.
Dr Ornish stated, "Changes in diet and lifestyle that we found in earlier research could reverse the progression of coronary heart disease may also affect the progression of prostate cancer as well. These findings suggest that men with prostate cancer who undergo conventional treatments may also benefit from making comprehensive lifestyle changes. This adds new evidence that changing diet and lifestyle may help to prevent prostate cancer."
August 10, 2005
Vitamins slow, fat may increase cataract development
The results of three studies conducted by researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University have found that while vitamins may help slow cataract development, dietary fat may increase the risk of this condition. Paul Jacques, DSc, who is the director of the Nutritional Epidemiology Program at the Center examined the effect of vitamin supplementation and fat intake on participants in the Nurses' Health Study, a long-term study that followed a large population of female nurses over a period of many years.
In the study that examined vitamin supplement intake, which was published in the April 2005 issue of the Archives of Ophthalmology (http://archopht.ama-assn.org/), it was found that ten years or more supplementation with vitamin E as well as thiamin and riboflavin retarded cataract progression. Earlier research conducted by Dr Jacques colleagues had revealed a similar protective benefit for vitamin C. In the second study, published in the American Journal of Clinical Nutrition (http://www.ajcn.org/), Dr Jacques' team discovered an increased risk of cataract with increased dietary intake of omega 6 or 3 fatty acids. These results were partly contradicted by the results of a further study, published in the American Journal of Epidemiology (http://aje.oxfordjournals.org/) which showed that while overall fat intake increased cataract risk, omega-3 fatty acids intake was associated with prevention of the condition.
Dr Jacques commented, "Our results suggest that vitamin supplementation, particularly long-term use of vitamin E, may slow down cataract development." He added, "The results of these studies provide added support for a relationship between nutrient intake and cataracts. Finding ways to delay age-related cataract formation through diet, or even through supplementation, would enhance the quality of life for many older people, but many questions regarding the role of diet in cataract prevention remain unanswered."
August 8, 2005
Elevated insulin associated with central nervous system inflammation
The results of study scheduled to be published in the October 2005 issue of the American Medical Association journal Archives of Neurology (http://archneur.ama-assn.org/) found a link between moderately high insulin levels and elevated levels of markers of inflammation and amyloid beta in plasma and cerebrospinal fluid. Amyloid beta is a substance found in the plaques that form in the brains of patients with Alzheimer's disease (AD). An increase in amyloid beta and inflammation could contribute to the development of the disease.
Mark A Fishel MD of the University of Washington in Seattle, and colleagues administered insulin and dextrose (in order to elevate insulin levels without elevating blood sugar) to 16 healthy adults aged 55 to 81. Plasma and cerebrospinal fluid levels of interleukin 1a, interleukin 1B, interleukin 6, tumor necrosis factor alpha, amyloid beta, norepinephrine, transthyretin and apolipoprotein E were measured. In addition, F2-isoprostane, a marker of lipid peroxidation, was measured in cebrospinal fluid.
The team found an association between elevated insulin and F2-isoprostane as well as cerebrospinal fluid but not plasma cytokines interleukin 1a, 1B and 6, and tumor necrosis factor alpha. Amyloid beta was increased in cerebrospinal fluid and in plasma.
The authors conclude, "Although this model has obvious relevance for diabetes mellitus, hyperinsulinemia and insulin resistance are widespread conditions that affect many nondiabetic adults with obesity, impaired glucose tolerance, cardiovascular disease, and hypertension. Our results provide a cautionary note for the current epidemic of such conditions, which, in the context of an aging population, may provoke a dramatic increase in the prevalence of AD. More encouragingly, greater understanding of insulin's role in AD pathogenesis may lead to novel and more effective strategies for treating, delaying, or even preventing this challenging disease."
August 5, 2005
Low folate in mothers means low birth weight babies
The July 2005 issue of the British Journal of Nutrition published the findings of researchers at the University of Newcastle upon Tyne that expectant mothers with deficient levels of the B vitamin folate have a greater risk of delivering babies with low birth weight. Low birth weight, defined as less than 5 pounds 8 ounces, is involved in 65 percent of infant deaths and increases the risk of severe disability in those who survive.
Dr Caroline Relton, of the University of Newcastle upon Tyne's School of Clinical Medical Sciences and colleagues measured folate in blood samples drawn during early prenatal visits of 998 expectant mothers in northwest England. Participants provided lifestyle information via questionnaires. Following the mother's deliveries, the newborns' weights were found to be positively associated with folate levels.
Folate may be necessary for a healthy birth weight because it is needed by the unborn child for growth and gene expression. Women who reported smoking had lower blood folate levels, which could explain the greater incidence of low birth weights observed in the children of smokers.
The study marks the first time that folate levels commonly seen in British mothers in early pregnancy have been associated with infant birth weight. Dr Relton commented, "Folic acid is highly important in preventing birth defects which affect a small number of pregnancies. This study suggests that it is also important in every pregnancy to help the developing baby reach a healthy birth weight. However, many women are missing this critical window in the first few weeks of gestation during which their baby really needs folic acid to grow and develop. The evidence from this study strengthens the argument for fortifying everyday foods like bread and cereals with folic acid."
August 1, 2005
Family of genes involved in life extension
A report published online on July 28 2005 in the journal Science (http://www.sciencemag.org/) revealed other genes in addition to Sir2 that control lifespan. Previous research had discovered that yeast and fruit flies on calorie restricted diets did not exhibit the usual resultant life extension effects if they lacked the Sir2 gene, which suggested that the gene is involved in determining lifespan. However, other findings have indicated that additional genes are involved in the process. Earlier research conducted by Sinclair's team had found a gene in yeast called PNC1, which regulates the Sir2 family of genes, and is triggered by environmental stressors such as severe calorie restriction.
For the current research, David A Sinclair, who is the Director of the Paul F. Glenn Laboratories for Aging Research at Harvard Medical School, and colleagues at Harvard and the University of California Davis, worked with S. cerevisiae, a yeast that has been studied in a number of previous life extension studies. They searched for genes that could increase lifespan similarly to Sir2, by looking for their effect on ribosomal DNA silencing, which has been linked with longevity. The team discovered four "cousins" of Sir2 that also extend lifespan, which suggests that the "family" of Sir2 genes is involved in the control of lifespan.
The finding has the potential to be used in the development of life extension drugs, or drugs to treat conditions associated with aging. Dr Sinclair commented, "We think these new Sir2 genes are as important as any longevity genes discovered so far. There is a growing realization from the aging field that we might finally understand how to control certain aspects of the aging process and one day have drugs that can fight some of the disabilities the process causes."
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