July 23, 2007, 5:22 PM CT
New joint replacement material
Massachusetts General Hospital (MGH) surgeons have performed the first total hip replacement using a joint socket lined with a novel material invented at the MGH. An advance over first-generation highly crosslinked polyethylene, which was also developed at MGH and significantly reduced a serious complication of early hip implants, the new material may be applied in replacements for a wider variety of joints in a more diverse group of patients.
We think this material could be used for any joint in the body and in any implant design, even those demanding higher flexion and more mobility, says Orhun Muratoglu, PhD, co-director of the Harris Orthopdics Biomechanics and Biomaterials Laboratory (OBBL) at MGH, who developed the new material in collaboration with researchers at the Cambridge Polymer Group.
Total replacements for hips and other joints were developed in the late 1960s, but it soon became apparent that hip implants could start loosening about 5 years after surgery and would eventually fail completely. A team led by William Harris, MD, DSc, now director emeritus of the MGH OBBL, investigated this complication and observed that long-term friction of the implants head against the polyethylene-lined joint socket would break off small particles of polyethylene. The bodys immune system reacted against these foreign particles, eventually destroying adjacent bone tissue and causing the implant to loosen a condition called periprosthetic osteolysis.........
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July 23, 2007, 5:17 PM CT
After Implant Of Cochlear Device
Cochlear implantselectronic devices inserted surgically in the ear to allow deaf people to hearmay restore normal auditory pathways in the brain even after a number of years of deafness.
The results imply that the brain can reorganize sound processing centers or press into service latent ones based on sound stimulation. Jeanne Guiraud, PhD, and his colleagues at the University of Lyon, Edouard Herriot University Hospital, and Advanced Bionics, a firm that makes cochlear implants, worked with deaf subjects from 16 to 74 years old and observed that younger subjects and those with a shorter history of deafness showed changes that mirrored patterns in people with normal hearing more closely. The results were reported in the July 18 Journal of Neuroscience
"The results imply a restoration to some extent of the normal organization through the use of the cochlear implant, says Manuel Don, PhD, of the House Ear Institute in Los Angeles. They also claim to find ties between the degree of restored organization and a hearing task. Such ties are of enormous importance in evaluating cochlear implant benefits. Don was not involved in this study.
Guiraud and her team studied 13 profoundly deaf adults who had received cochlear implants, on average, eight months before the study. Electrical stimulation to the ear allowed the team to locate where in the brains auditory cortex various frequencies were processed and come up with a map for these tones. Their results demonstrated that in people who had cochlear implants for at least three months, normal frequency organization was somewhat restored.........
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July 23, 2007, 5:13 PM CT
Process For Allergen-free Peanuts
An agricultural researcher at North Carolina Agricultural and Technical State University has developed a simple process to make allergen-free peanuts. The new process thought to bea first for food science could provide relief to millions of peanut allergy sufferers, and be an enormous boon to the entire peanut industry.
Doug Speight of the N.C. A&T Office of Outreach and Technology Transfer said food companies are showing a strong interest in licensing the process, which does not degrade the taste or quality of treated peanuts, and might even render them easier to process for use as a food ingredient.
Immunoassays showed 100 percent inactivation of peanut allergens in whole roasted kernels, and the processed peanuts showed no reaction in tests on human serums from severely allergic individuals. The inventor, Dr. Mohamed Ahmedna, is optimizing the process further to remove allergens from other foods.
We are extremely pleased that we were able to find such a simple solution to a vexing problem that has enormous economic and public health ramifications, both for peanut sensitive individuals, and the food industry as a whole, said Ahmedna, associate professor of food science in N.C. A&Ts School of Agriculture and Environmental Sciences.
Peanut and tree nut allergies are the most severe of all food allergies, affecting approximately 3 million Americans, and causing 100 150 deaths from anaphylactic shock annually and a number of more hospitalizations. In industrialized nations, the allergy has been rapidly increasing in children, for causes that are not entirely understood. One study showed that between 1997 and 2002, peanut allergies in children doubled in the United States. Today, an estimated one percent of all children suffer from the allergy.........
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July 23, 2007, 5:11 PM CT
NSAIDs treatment can reduce colorectal cancer risk
A study of Medicare patients with osteoarthritis provides additional evidence that non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin reduce the risk of colorectal cancer. Earlier investigations of the drugs impact on tumor development could not rule out the possibility that an observed protective effect was caused by other preventive health care measures. The current study, led by a Massachusetts General Hospital (MGH) physician, appears in the August 2007 Journal of General Internal Medicine.
This is good news for people who take NSAIDs regularly for osteoarthritis, says Elizabeth Lamont, MD, MS, of the MGH Cancer Center, the studys lead author. Eventhough patients face risks such as bleeding or kidney damage from this treatment, they probably are at a lower risk of developing colorectal cancer. Because of the risks posed by the dosage used to treat osteoarthritis, she and her co-authors stress that currently available NSAIDs should not be used solely to prevent cancer.
Earlier randomized trials clearly showed that NSAID therapy can prevent the development of premalignant colorectal polyps, but whether or not such treatment also reduces the risk of invasive colorectal cancer has still not been confirmed. Those trials used relatively low doses of aspirin and showed no significant differences in colorectal cancer rates between the aspirin and placebo groups. While a number of findings based on observation have shown a protective effect of NSAIDs against colorectal cancer, interpretation of some of those results may have been clouded by other healthy behaviors of the participants.........
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July 23, 2007, 4:50 PM CT
Unintended Pregnancy Predicts Feelings That Parenting Is A Burden
The relationship between a mother and her infant is believed by a number of to be the foundation of healthy childhood development, but scientists at the University of Missouri-Columbia have found pregnancy acceptance to be the first step in forming the mother/child bond.
Analyzing data collected from the national evaluation of the Early Head Start program, Jean Ispa, professor and co-chair of the Department of Human Development and Family Studies in the College of Human Environmental Science (HES), and her colleagues, found associations between how accepting mothers were of being pregnant and their toddlers' security of attachment. In the study, 173 young, low-income black mothers, who either were pregnant or had delivered within the past 11 months, were questioned regarding their feelings about pregnancy. When children were about a year old, their attachment security to their mothers was assessed.
"The relation between mothers' pregnancy acceptance and toddler attachment security is noteworthy because if attachment problems continue into the later years, the child could have self-esteem problems, difficulty learning and a harder time forming relationships," Ispa said.
The scientists also observed that mothers who were not accepting of their pregnancies had a greater tendency to later feel that parenting is burdensome. These findings suggest a need for policies that support reproductive education, as per Ispa. In addition, pregnant women who struggle to accept motherhood may benefit from policies that encourage social service professionals to screen for low acceptance of pregnancy and provide extra support to women who are not happy to be pregnant.........
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July 23, 2007, 4:45 PM CT
Smokers who see more ads for smoking-cessation products
The more magazine ads smokers see for the nicotine patch and other quit-smoking aids, the more likely they are to try to quit smoking and be successful -- even without buying the products, finds a new Cornell study.
"We believe that the reason may be that important 'spillover effects' from advertising may be occurring, which has important implications for advertising for a wide range of health products," said Alan Mathios, professor of policy analysis and management at Cornell and a co-author of the study, published in an upcoming issue of the Journal of Political Economy and winner of best conference paper at the 2007 American Marketing Association's Public Policy and Marketing Conference, May 31-June 2, in Washington, D.C.
Mathios noted that the results of this study may also apply to other types of pharmaceutical advertising. For example, when patients discuss with their physicians an advertised drug that lowers cholesterol, physicians will often recommend such health behavior changes as diet and exercise, creating a positive spillover effect from the advertising.
Using databases on the consumer behavior and magazine-reading habits of 28,303 current or former smokers and advertising data in 26 consumer magazines, Mathios and three Cornell colleagues explored the impact of advertising of smoking-cessation products on quitting decisions.........
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July 23, 2007, 3:18 PM CT
New Method To Combat HIV
Scientists at the University of Minnesotas Center for Drug Design have developed a new method to combat HIV/AIDS, potentially replacing the traditional cocktail drug approach.
The new approach proven accurate in lab tests merges the features of two antiviral agents into one drug, achieving the same effect as when two or more drugs are taken separately. The cocktail approach most usually prescribed to HIV-infected patients is expensive and high in toxicity because a number of drugs are taken at one time.
The scientists named the new concept Portmanteau Inhibitors, and the results were published in a July 4 issue of the Journal of Medicinal Chemistry. The principal researcher is Robert Vince, Ph.D., director of the center and a professor of medicinal chemistry in the College of Pharmacy.
Its one drug that does the same thing as two independent drugs would do, Vince said. Its a new approach in HIV/AIDS therapy.
Besides remedying cost and toxicity problems, a Portmanteau Inhibitor is less likely to develop resistance from the virus because of its multifaceted approach. Most importantly, research observed that the separate components of the drug did not interfere with each other while attacking HIV.
One drug is not durable. It develops resistance very quickly, said Zhenqiang Wang, Ph.D., a researcher in the Center for Drug Design, and co-investigator of the research. This makes it much more difficult for resistance to develop.........
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July 19, 2007, 10:42 PM CT
How Diet And Exercise Enhance Longevity
The traditional prescriptions for a healthy lifesensible diet, exercise and weight controlextend life by reducing signaling through a specific pathway in the brain, as per Howard Hughes Medical Institute scientists who discovered the connection while studying long-lived mice.
They said their findings underscore the importance of maintaining a healthy lifestyle and may also offer promising research directions for understanding and treating diabetes and Alzheimers disease.
Howard Hughes Medical Institute investigator Morris F. White and colleagues published their findings in the July 20, 2007, issue of the journal Science.
Akiko Taguchi and Lynn Wartschow in Whites laboratory in the Division of Endocrinology at Childrens Hospital Boston and Harvard Medical School were co-authors of the research article.
In their experiments, the scientists sought to understand the role of the insulin-like signaling pathway in extending lifespan. This pathway governs growth and metabolic processes in cells throughout the body. The pathway is activated when insulin and insulin-like growth factor-1 switch on proteins inside the cell called insulin receptor substrates (Irs).
Other scientists had shown that reducing the activity of the pathway in roundworms and fruitflies extends lifespan. Despite those tantalizing clues, White said, The idea that insulin reduces lifespan is difficult to reconcile with decades of clinical practice and scientific investigation to treat diabetes.........
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July 19, 2007, 10:35 PM CT
Genes Which Battle Hepatitis C
Joint research by Dr. Leonid Brodsky, of the Institute of Evolution of the University of Haifa, and Dr. Milton Taylor, of Indiana University, led to the discovery of a mathematical method which can identify which genes in our bodies conduct the battle against the various viruses that attack us. In their research, they identified 37 genes out of 22,000 possible genes which fight the hepatitis C virus.
"When we know which genes are responsible for fighting the viruses which attack our liver, we will be able to look for the medications which will activate these genes most favorably," said Dr. Brodsky. The team conducted clinical trials, supported by the Health National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) of the US National Institutes of Health (NIH), which included 400 patients at eight different centers in the United States. The results would be reported in the prestigious journal PLOS ONE.
The hepatitis C virus, found mostly among a number of patients who have had a blood transfusion or who share needles, attacks the liver and in extreme cases can cause cancer of the liver. At present, there is one well know medication, interferon, used to treat the virus; however, while some patients respond to the therapy with interferon, others do not. In this research, the clinical study was combined with the mathematical model developed by Dr. Brodsky. The study identified 37 genes which are key for patient response to therapy.........
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July 19, 2007, 10:30 PM CT
Self-injury in high-school students
Non-Suicidal Self-Injury the deliberate, direct destruction of body tissue without conscious suicidal intent is a relatively common occurrence for adolescents in high school, a new study suggests. Led by scientists at The Miriam Hospital and The Warren Alpert Medical School of Brown University, nearly half of the teens studied endorsed some form of Non-Suicidal Self-Injury (NSSI) in the past year, most frequently biting self, cutting/carving skin, hitting self on purpose, and burning skin.
The research is reported in the August 2007 issue of Psychological Medicine.
The findings are important because it suggests that NSSI is more prevalent among adolescents in the general population than previously thought, says lead author Elizabeth Lloyd-Richardson, PhD, a psychology expert at The Miriam Hospital and assistant professor of psychiatry and human behavior at The Warren Alpert Medical School of Brown University.
If this is the case - its essentially a wake-up call to take better notice of these behaviors in the community and learn how to help teens manage stress without harming themselves, adds Lloyd-Richardson.
Scientists decided to explore the frequency and breadth of NSSI engaged in by teens in the community because little is known about self-harming behavior in this particular population.........
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