January 12, 2009, 6:42 PM CT
Epidural anesthesia is safe
The largest ever prospective study [1,2] into the major complications  of epidurals and spinal anaesthetics reported in the British Journal of Anaesthesia
today (Monday 12 January 2009) concludes that prior studies have over-estimated the risks of severe complications of these procedures. The study concludes that the estimated risk of permanent harm following a spinal anaesthetic or epidural is lower than 1 in 20,000 and in a number of circumstances the estimated risk is considerably lower.
The study finds that the risk of permanent injury (of whatever severity) is about 1 in 23-50,000. In betting terms, the odds of being badly injured by an epidural or spinal anaesthetic are considerably better than 20,000-to-1 against. The risk of being paralysed by one of these injections is 2-3 times rarer than of suffering any permanent harm. The risk for women requiring pain relief for labour or Caesarean section is lower still, the most pessimistic estimate of permanent harm is 1 in 80,000 and it appears to be much lower. A similarly low risk was found in procedures performed for chronic pain and in children.
The study also finds that the risk of harm when an epidural is used for surgery is considerably higher than the estimated risk of using it during childbirth: between 1 in 6,000 and 1 in 12,000. However, while these figures may appear high, they too are still considerably lower than a number of prior estimates, and Dr Tim Cook, a consultant anaesthetist at the Royal United Hospital, Bath who led the project believes there are other reasons to explain these figures: "It has been known for a long time that these complications occur more often after surgery. The reason is likely to be that a number of of these patients are elderly with medical problems and that the process of having surgery itself increases risks. Major surgery leads to severe pain and may mean that an epidural has to stay in place for several days. Epidurals are generally only used for the biggest most painful operations and it is probably the least fit patients who have the most to gain from these techniques. What the project has shown is that a number of complications of epidurals occur after major surgery in elderly unhealthy patients. The risks must also be balanced against the generally accepted benefits of epidurals".........
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January 12, 2009, 6:28 AM CT
Fighting cholesterol with synthetic HDL
Buttery Christmas cookies, eggnog, juicy beef roast, rich gravy and creamy New York-style cheesecake. Happy holiday food unfortunately can send blood cholesterol levels sky high.
Northwestern University researchers now offer a promising new weapon -- synthetic high-density lipoprotein (HDL), the "good" cholesterol -- that could help fight chronically high cholesterol levels and the deadly heart disease that often results.
The scientists successfully designed synthetic HDL and show that their nanoparticle version is capable of irreversibly binding cholesterol. The synthetic HDL, based on gold nanoparticles, is similar in size to HDL and mimics HDL's general surface composition.
The study is published online by the Journal of the American Chemical Society
"We have designed and built a cholesterol sponge. The synthetic HDL features the basics of what a great cholesterol drug should be," said Chad A. Mirkin, George B. Rathmann Professor of Chemistry in the Weinberg College of Arts and Sciences, professor of medicine and professor of materials science and engineering. Mirkin and Shad Thaxton, M.D., assistant professor of urology in Northwestern's Feinberg School of Medicine, led the study.
"Drugs that lower the bad cholesterol, LDL, are available, and you can lower LDL through your diet, but it is difficult to raise the good cholesterol, HDL," said Mirkin. "I've taken niacin to try and raise my HDL, but the side effects are bad so I stopped. We are hopeful that our synthetic HDL will one day help fill this gap in useful therapeutics".........
Posted by: Daniel Read more Source
January 12, 2009, 6:26 AM CT
Where am I?
We've all experienced the feeling of not knowing where we are. Being disoriented is not pleasant, and it can even be scary, but luckily for most of us, this sensation is temporary. The brain employs many tricks to reorient us, keeping our confusion to a minimum and quickly pointing us in the right direction. Research has suggested that animals and young children mainly rely on geometric cues (e.g. lengths, distances, angles) to help them get reoriented. Human adults, however, can also make use of feature cues (e.g. color, texture, landmarks) in their surrounding area. But which method do we use more often? Psychology experts Kristin R. Ratliff from the University of Chicago and Nora S. Newcombe from Temple University conducted a set of experiments investigating if human adults have a preference for using geometric or feature cues to become reoriented.
The first experiment took place in either a large or small white, rectangular room with a landmark (a big piece of colorful fabric) hanging on one wall. The study volunteers saw the researcher place a set of keys in a box in one of the corners. The volunteers were blindfolded and spun around, to become disoriented. After removing the blindfold, they had to point to the corner where the keys were. After a break, the volunteers were told the experiment would be repeated, eventhough they wouldn't watch the researcher hide the keys. Unbeknownst to them, during the break the scientists moved the landmark to an adjacent wallthis change forced the volunteers to use either geometric cues or feature cues, but not both, to reorient themselves and locate the keys. For the second experiment, the scientists used a similar method, except they switched room sizes (the volunteers moved from a larger room to a smaller room and vice versa) during the break.........
Posted by: Daniel Read more Source
January 12, 2009, 6:24 AM CT
Insulin levels may have a say in breast cancer risk
Higher-than-normal levels of insulin place postmenopausal women at increased risk of breast cancer, scientists at Albert Einstein College of Medicine of Yeshiva University report. Their findings, reported in the January 7 issue of the Journal of the National Cancer Institute
, suggest that interventions that target insulin and its signaling pathways may decrease breast cancer risk in these women.
Breast cancer is the most common cancer among women in the United States. Last year, approximately 182,000 women were diagnosed with breast cancer and more than 40,000 died from the disease. The majority of breast cancers arise in women past the age of menopause.
Obesity is a well-established risk factor for postmenopausal breast cancer, but just how obesity and breast cancer are connected is unclear. A number of scientists have assumed that the link is estrogena hormone that is known to increase breast-cancer risk and is found at higher-than-average levels in obese women. But obese women also have other hormonal imbalances that may play a role in triggering breast cancer. One such imbalance is elevated levels of insulin, which stimulates the growth of breast cells in tissue culture. The Einstein study is the first to prospectively identify insulin's role in breast cancer while controlling for estrogen levels.........
Posted by: Janet Read more Source
January 12, 2009, 6:19 AM CT
New genes that fuse in cancer
Using new technologies that make it easier to sequence the human genome, scientists at the University of Michigan Comprehensive Cancer Center have identified a series of genes that become fused when their chromosomes trade places with each other. These recurrent gene fusions are believed to be the driving mechanism that causes certain cancers to develop.
The gene fusions discovered could potentially serve as a marker one day for diagnosing cancer or as a target for future drug development.
In the newly released study, published in Nature
, the scientists identified several gene fusions in prostate cancer cells. Some of the fusions were seen in multiple cell lines studied, while other gene fusions appeared only once. The fusions were found only in cancer cells, and not in normal cells.
"We defined a new class of mutations in prostate cancer. The recurrent fusions are believed to be the driving mechanism of cancer. But we found other fusions as well, some of which were unique to individual patients. Our next step is to understand if these play a role in driving disease," says Arul Chinnaiyan, M.D., Ph.D., director of the Michigan Center for Translational Pathology and S.P. Hicks Endowed Professor of Pathology at the U-M Medical School.
Chinnaiyan's team was the first to identify rearrangements in chromosomes and fused genes in prostate cancer. Gene fusions had previously been known to play a role in blood cell cancers such as leukemia and lymphoma, and in Ewing's sarcoma.........
Posted by: Janet Read more Source
January 12, 2009, 6:17 AM CT
Eithout becoming obese
Berkeley -- Scientists at the University of California, Berkeley, have identified a new enzyme that plays a far more important role than expected in controlling the breakdown of fat. In a newly released study would be published Jan. 11 in the journal Nature Medicine
, scientists report that mice that have had this enzyme disabled remained lean despite eating a high-fat diet and losing a hormone that suppresses appetite.
"We have discovered a new enzyme within fat cells that is a key regulator of fat metabolism and body weight, making it a promising target in the search for a therapy for human obesity," said Hei Sook Sul, UC Berkeley professor of nutritional sciences and toxicology and principal investigator of the research.
Sul's research team includes the three co-main authors of the paper, all from UC Berkeley's Department of Nutritional Sciences and Toxicology: Kathy Jaworski, former post-doctoral researcher; Maryam Ahmadian, graduate student; and Robin Duncan, post-doctoral fellow.
The enzyme in the spotlight, adipose-specific phospholipase A2 (AdPLA), is found in abundance only in fat tissue. AdPLA sets off a chain of events that increases levels of a signaling molecule called prostaglandin E2 (PGE2), which suppresses the breakdown of fat. Mice that have no AdPLA have lower PGE2 levels and a higher rate of fat metabolism.........
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January 12, 2009, 6:14 AM CT
New evidence for warburg theory of cancer
German scientist Otto H. Warburg's theory on the origin of cancer earned him the Nobel Prize in 1931, but the biochemical basis for his theory remained elusive.
His theory that cancer starts from irreversible injury to cellular respiration eventually fell out of favor amid research pointing to genomic mutations as the cause of uncontrolled cell growth.
Seventy-eight years after Warburg received science's highest honor, scientists from Boston College and Washington University School of Medicine report new evidence in support of the original Warburg Theory of Cancer.
A descendant of German aristocrats, World War I cavalry officer and pioneering biochemist, Warburg first proposed in 1924 that the prime cause of cancer was injury to a cell caused by impairment to a cell's power plant or energy metabolism found in its mitochondria.
In contrast to healthy cells, which generate energy by the oxidative breakdown of a simple acid within the mitochondria, tumors and cancer cells generate energy through the non-oxidative breakdown of glucose, a process called glycolysis. Indeed, glycolysis is the biochemical hallmark of most, if not all, types of cancers. Because of this difference between healthy cells and cancer cells, Warburg argued, cancer should be interpreted as a type of mitochondrial disease.........
Posted by: Janet Read more Source
January 8, 2009, 10:11 PM CT
Hormone therapy and colorectal cancer
The combination of estrogen plus progestin, which women stopped taking in droves following the news that it may increase their risk of breast cancer, may decrease their risk of colorectal cancer, as per a report reported in the recent issue of Cancer Epidemiology, Biomarkers and Prevention
, a journal of the American Association for Cancer Research.
"In comparison to women who had never taken these hormones, the use of estrogen plus progestin was linked to a reduced risk of colorectal cancer," said Jill R. Johnson, M.P.H., a doctoral student at the University of Minnesota School of Public Health.
The largest risk reduction, approximately 45 percent, was seen among women who had completed use of estrogen plus progestin five or more years previously.
Johnson and her colleagues extracted data from 56,733 postmenopausal women who participated in the Breast Cancer Detection Demonstration Project follow-up study. Hormone treatment use and other risk factors were ascertained through telephone interviews and mailed questionnaires between 1979 and 1998. During an average 15 years of follow-up, Johnson and his colleagues identified 960 new cases of colorectal cancer in this population.
Any use of estrogen treatment was linked to a 17 percent reduced risk in colorectal cancer. Among those who used estrogen, the largest reductions were seen among those who were current users (25 percent reduced risk) and users of ten or more years duration (26 percent reduced risk).........
Posted by: Sue Read more Source
January 8, 2009, 10:06 PM CT
Surprisingly high tolerance for racism
White people do not get as upset when confronted with racial prejudice as they think they will, a study by scientists at Yale University, York University, and the University of British Columbia suggests. This indifference helps explains why racism persists even as the United States prepares to celebrate the inauguration of Barack Obama, scientists say.
Non-black participants who experienced a racial slur against a black person did not get as upset or react against the racist remark as they predicted they would, as per a research studyreported in the Jan. 9 issue of the journal Science
This acquiescence in the face of racism leads to its perpetuation, because numerous studies have shown that people confronted after making slurs are much less likely to repeat the behavior in public or in private, said John Dovidio, Yale psychology expert and a co-author of the study.
"We have an unconscious bias that affects us in significant ways," Dovidio said.
The scientists studied 120 non-black participants who volunteered for the experiment and either directly experienced a racial incident or had the incident described to them. The first group watched a black man, posing as a fellow participant, slightly bump a white confederate also posing as a participant. After the black man left the room, the white confederate either said nothing, or "I hate it when black people do that," or said, "clumsy n____." Other groups did not directly experience the event but either read about it or watched it on videotape and were asked to predict their responses to the events.........
Posted by: Janet Read more Source
January 8, 2009, 10:04 PM CT
Cancer prevention properties of black raspberries
A study published in Cancer Prevention Research
, a journal of the American Association for Cancer Research, identifies components of black raspberries with chemopreventive potential.
Scientists at the Ohio State Comprehensive Cancer Center observed that anthocyanins, a class of flavonoids in black raspberries, inhibited growth and stimulated apoptosis in the esophagus of rats treated with an esophageal carcinogen.
"Our data provide good evidence that anthocyanins are important for cancer prevention," said the study's main author, Gary D. Stoner, Ph.D., a professor in the department of internal medicine at Ohio State University.
Stoner and his team of scientists fed rats an anthocyanin-rich extract of black raspberries and observed that the extract was nearly as effective in preventing esophageal cancer in rats as whole black raspberries containing the same concentration of anthocyanins. This study demonstrates the importance of anthocyanins as preventive agents in black raspberries and validated similar in vitro findings. It is among the first to look at the connection between anthocyanins and cancer prevention in vivo.
Stoner and colleagues have conducted clinical trials using whole berry powder, which has yielded some promising results, but mandatory patients to take up to 60 grams of powder a day. "Now that we know the anthocyanins in berries are almost as active as whole berries themselves, we hope to be able to prevent cancer in humans using a standardized mixture of anthocyanins," said Stoner.........
Posted by: Janet Read more Source