August 13, 2009, 6:53 AM CT

Cancer mortality rates experience steady decline

The number of cancer deaths has declined steadily in the last three decades. Eventhough younger people have experienced the steepest declines, all age groups have shown some improvement, as per a recent report in Cancer Research, a journal of the American Association for Cancer Research.

"Our efforts against cancer, including prevention, early detection and better therapy, have resulted in profound gains, but these gains are often unappreciated by the public due to the way the data are commonly reported," said Eric Kort, M.D., who completed the study while employed as a research scientist at the Van Andel Research Institute in Grand Rapids, Mich.

Scientists examined cancer mortality rates stratified by age and observed that for individuals born since 1925, every age group has experienced a decline in cancer mortality. The youngest age groups have experienced the steepest decline at 25.9 percent per decade, but even the oldest groups have experienced a 6.8 percent per decade decline.

The public often hears about incidence rates, which continue to rise across a number of cancer types, or mortality proportions, with the World Health Organization's assertion that death from cancer will surpass death from heart disease by 2010. Both these calculations are accurate, Kort said, but they ask the wrong question. In particular, the often-quoted WHO statistic can be misleading......... Posted by: Janet      Read more         Source

August 13, 2009, 6:52 AM CT

MRI may cause more harm than good in newly diagnosed early breast cancer

A new review says using magnetic resonance imaging (MRI) before surgery to assess the extent of early breast cancer has not been shown to improve surgical planning, reduce follow-up surgery, or reduce the risk of local recurrences. The review, appearing early online in CA: A Cancer Journal for Clinicians, says evidence shows that MRI increases the chances of more extensive surgery over conservative approaches, with no evidence that it improves surgical care or prognosis.

Randomized controlled trials have shown women with early stage breast cancer who are treated with breast-conservation treatment (local excision and radiotherapy) have the same survival rates as those who undergo mastectomy. Recently, MRI has been introduced in preoperative staging of the affected breast in women with newly diagnosed breast cancer because it detects additional areas of cancer that do not show up on conventional imaging. In the current review, Nehmat Houssami, MBBS, Ph.D., of the University of.

Sydney, Australia, and Daniel F. Hayes, M.D., of University of Michigan Comprehensive Cancer Center, Ann Arbor, Mich., evaluated available data on preoperative MRI's detection capability and its impact on therapy. The use of preoperative MRI scans in women with early stage breast cancer has been based on assumptions that MRI's detection capability in this setting will improve surgical therapy by improving surgical planning, potentially leading to a reduction in re-excision surgery, and by guiding surgeons to remove additional disease detected by MRI and potentially reducing recurrence in the treated breast. The authors say emerging data show that this approach to local staging of the breast leads to more women being treated with mastectomy without evidence of improvement in surgical outcomes or long-term prognosis......... Posted by: Janet      Read more         Source

August 13, 2009, 6:50 AM CT

Sleep patterns in children and teenagers could indicate risk for depression

Sleep patterns can help predict which adolescents might be at greatest risk for developing depression, a researcher at UT Southwestern Medical Center has found in a five-year study.

Sleep is a biological factor known to be linked to adult depression. Depressed adults experience rapid-eye-movement (REM) sleep earlier in the sleep cycle than people who are not depressed. Until this study, available online and in the July edition of Neuropsychopharmacology, it had been unclear whether this relationship held true in adolescents.

Dr. Uma Rao, professor of psychiatry at UT Southwestern and main author of the study, observed that adolescents with a familial risk for depression but without a depression diagnosis experienced shorter REM latency, meaning they reached the REM stage more quickly. Those adolescents were more likely to develop depression by the end of the five-year study period than those who reached REM sleep later in the cycle.

"Sleep is probably more helpful in determining who is at risk for developing depression than in being a diagnostic marker for depression since REM latency of those adolescents was shorter before they even developed the illness," Dr. Rao said.

Adolescent depression is complex to prevent and to treat in part because baseline levels of sleep and other factors used to diagnosis depression are not clearly defined. For example, in clinical studies, adolescents without manifestation of mental illness can be labeled erroneously as control group members because they haven't yet reached the highest-risk period for developing depression mid- to late-adolescence and early adulthood......... Posted by: JoAnn      Read more         Source

August 11, 2009, 11:22 PM CT

Successfully reverse multiple sclerosis in mice

A new experimental therapy for multiple sclerosis (MS) completely reverses the devastating autoimmune disorder in mice, and might work exactly the same way in humans, say scientists at the Jewish General Hospital Lady Davis Institute for Medical Research and McGill University in Montreal.

MS is an autoimmune disease in which the body's own immune response attacks the central nervous system, almost as if the body had become allergic to itself, leading to progressive physical and cognitive disability.

The new therapy, appropriately named GIFT15, puts MS into remission by suppressing the immune response. This means it might also be effective against other autoimmune disorders like Crohn's disease, lupus and arthritis, the scientists said, and could theoretically also control immune responses in organ transplant patients. Moreover, unlike earlier immune-supppressing therapies which rely on chemical pharamaceuticals, this approach is a personalized form of cellular treatment which utilizes the body's own cells to suppress immunity in a much more targeted way.

GIFT15 was discovered by a team led by Dr. Jacques Galipeau of the JGH Lady Davis Institute and McGill's Faculty of Medicine. The results were published August 9 in the prestigious journal Nature Medicine........ Posted by: Daniel      Read more         Source

August 11, 2009, 11:19 PM CT

Taking dex can improve high altitude exercise capacity

Taking dexamathasone prophlyactically may improve exercise capacity in some mountaineers, as per Swiss researchers. Dexamathasone, known popularly to climbers as "dex," has been used for years to treat altitude-related symptoms in mountaineers, but has never been tested for its ability to improve exercise capacity at high altitude.

"We have known that both tadalafil and dexamethasone are good for preventing high altitude pulmonary edema (HAPE) and dex for treating symptoms of acute mountain sickness (AMS). But we did not know whether they could also improve exercise capacity at altitude by reducing pulmonary hypertension, one of the important factors in altitude- related exercise limitations," said main authors Manuel Fischler, MD, of the University Hospital in Zurich, Switzerland, and Hans-Peter Brunner-La Rocca, of the University Hospital in Basel, Switzerland.

The results were reported in the August 15th issue of the American Journal of Respiratory and Critical Care Medicine, the journal of the American Thoracic Society.

The scientists recruited 23 mountaineers with a history of HAPE and administered baseline cardiopulmonary exercise tests a low elevation (490 meters, or 1607 feet). Subjects were tested for oxygen uptake kinetics by pedaling a stationary bike at a constant rate for six minutes, and then for exercise capacity by pedaling at 50 percent of their predicted maximum workload for one minute, then increasing output by 25 percent each additional minute until exhaustion, commonly after 8 to 12 minutes......... Posted by: Scott      Read more         Source

August 11, 2009, 11:17 PM CT

Toxic levels of Alzheimer's clusters in brain

Researchers have long suspected that Alzheimer's disease (AD) is caused by a small protein called the amyloid β-protein (Aβ). This protein clumps or binds to itself, eventually changing chemically to create brain protein deposits (plaques) that are characteristic of AD. However, recent studies have suggested that it is not the plaques that cause AD but rather these small, grape-like clusters of Aβ. These clusters vary in size, and the relationship between cluster size and their ability to kill nerve cells (toxicity) has never been determined accurately.

Until now. By creating various sizes of Aβ clusters in the lab that exactly match what forms in brains of those afflicted with AD, neurologists at UCLA have determined that toxicity increases dramatically as clusters increase in size from two to three to four Aβs. The scientists also report that eventhough the larger clusters are more toxic than smaller ones, the larger formations are relatively rare; smaller versions are numerous and thus are an inviting target for the development of new therapeutic drugs.

In addition, said David Teplow, senior author and a professor of neurology, developing the ability to make Aβ clusters in a very pure and precise way that duplicates what forms in AD brains will enable researchers to make detailed studies of their structures. This too will make development of future therapeutic drugs much easier and likely more successful. The research appears in the early on line edition of the Proceedings of the National Academy of Sciences (PNAS)......... Posted by: Daniel      Read more         Source

August 11, 2009, 11:16 PM CT

Mystery behind long-lasting memories

A newly released study by scientists at Wake Forest University School of Medicine may reveal how long-lasting memories form in the brain.

The scientists hope that the findings, now available online and scheduled to appear in an upcoming issue of Neuroscience, may one day help researchers develop therapys to prevent and treat conditions such as post-traumatic stress disorder.

"Eventhough a number of things are known about memories that form from repeat experiences, not much is known with regard to how some memories form with just one exposure," said Ashok Hegde, Ph.D., an associate professor of neurobiology and anatomy and the lead investigator on the study.

Researchers do know that people tend to remember extremely happy or sad occasions vividly because of the emotional connection, Hegde said. Extreme emotions trigger the release of a chemical in the brain called norepinephrine, which is correlation to adrenaline. That norepinephrine somehow helps memories last a long time some even a lifetime.

For example, he said, when a person asks, "Where were you when the 9/11 attacks happened?" most people can recall immediately where they were and what they were doing when they heard the news. They remember the moment as if it just happened because a national tragedy arouses emotion and emotion somehow makes memories last for a long time, Hegde explained......... Posted by: Daniel      Read more         Source

August 11, 2009, 11:13 PM CT

Oxygen treatment hastens memory loss

A 65-year-old women goes into the hospital for routine hip surgery. Six months later, she develops memory loss and is later diagnosed with Alzheimer's Disease. Just a coincidence? Scientists at the University of South Florida and Vanderbilt University don't think so. They suspect that the culprit precipitating Alzheimer's disease in the elderly women appears to be a routine administration of high concentrations of oxygen for several hours during, or following, surgery a hypothesis borne out in a recent animal model study.

Dr. Gary Arendash of the Florida Alzheimer's Disease Research Center at USF and Dr. L. Jackson Roberts II at Vanderbilt University used mice genetically altered to develop abnormal levels of the protein beta amyloid, which deposits in the brain as plaques and eventually leads to Alzheimer's-like memory loss as the mice age. They observed that young adult Alzheimer's mice exposed to 100-percent oxygen during several 3-hour sessions demonstrated substantial memory loss not otherwise present at their age. Young adult Alzheimer's mice exposed to normal air had no measurable memory loss, and neither did normal mice without any genetic predisposition for Alzheimer's disease.

The authors suggest that people genetically predisposed to Alzheimer's disease or with excessive amounts of beta amyloid in their brains are at increased risk of developing the disease earlier if they receive high concentrations of oxygen, known as hyperoxia. Their study is published online this month in NeuroReport........ Posted by: Daniel      Read more         Source

August 11, 2009, 11:10 PM CT

Powerful new therapy for asthma

University of Texas Medical Branch at Galveston scientists have observed that a single enzyme is apparently critical to most allergen-provoked asthma attacks and that activity of the enzyme, known as aldose reductase, can be significantly reduced by compounds that have already undergone clinical trials as therapys for complications of diabetes.

The discovery, made in experiments conducted with mice and in human cell cultures, opens the way to human tests of a powerful new therapy for asthma, which today afflicts more than 20 million Americans. Such a development would provide a badly needed alternative to current asthma treatment, which primarily depends on hard-to-calibrate inhaled doses of corticosteroids and bronchodilators, which have many side effects.

"Oral administration of aldose reductase inhibitors works effectively in experimental animals," said UTMB professor Satish Srivastava, senior author of a paper on the discovery appearing in the Aug. 6 issue of the journal PLoS One "If these drugs work as well in humans as they do in animals you could administer them either orally or in a single puff from an inhaler and get long-lasting results."

Srivastava and colleagues (postdoctoral fellows Umesh Yadav and Leopoldo Aguilera-Aguirre, associate professor Kota Venkata Ramana, professor Istvan Boldogh and LSU Health Sciences Center assistant professor Hamid Boulares) focused on aldose reductase inhibition as a possible asthma treatment after establishing an essential role for the enzyme in other diseases also characterized by inflammation. In disorders such as colon cancer, atherosclerosis, sepsis and uveitis, the Srivastava team has found, cells are hit by a sudden overload of reactive oxygen species (varieties of oxygen and oxygen compounds that are particularly eager to react with other molecules). The result is a chain of biochemical reactions that leads the cells' genetic machinery to crank out a barrage of inflammatory signaling proteins. These summon immune system cells and generate even more reactive oxygen species, producing a vicious cycle of ever-increasing inflammation......... Posted by: JoAnn      Read more         Source

August 11, 2009, 11:10 PM CT

No-Needle Approach to Prevent Blood Clots

The dean of the University of Oklahoma College of Public Health and a team of researchers worldwide have found a better way to prevent deadly blood clots after joint replacement surgery - a major problem that results in thousands of unnecessary deaths each year. The research appears this week in the New England Journal (NEJM).

The research team, which includes researchers from Oklahoma, Denmark, Australia and Canada, set out to find a better way to prevent blood clots without increasing the risk of bleeding. Blood clots, known as deep-vein thrombosis (DVT), affect the large veins in the lower leg and thigh. If the clot breaks free and moves through the bloodstream, it can lodge in the lungs, a condition known as pulmonary embolism (PE), which is often fatal. Pulmonary embolism is the most common preventable cause of sudden death after surgery.

Current preventive therapys include uncomfortable injections and one oral anti-clotting medicine that is difficult for patients and physicians to manage. Scientists wanted to find something better.

In a double-blind study of more than 3,000 patients, scientists tested a new type of anti-clotting drug called Apixaban, which is an oral medication. The medicine proved just as effective at preventing blood clots and reduced the risk of bleeding by half. Most importantly for patient convenience, it was much easier to use......... Posted by: Scott      Read more         Source