August 28, 2007, 9:26 PM CT
More prostate cancer screening has little effect
More prostate cancers were detected among men who were screened every two years than men screened every four years, as per a research studypublished online August 28 in the Journal of the National Cancer Institute
But the shorter time between screenings did not reduce the number of aggressive cancers found between the scheduled screening tests.
Since the introduction of PSA (prostate specific antigen) testing in the late 1980s, the occurence rate of prostate cancer has risen dramatically. The rise is mainly due to widespread screening of asymptomatic men. Screening for prostate cancer is a controversial issue because evidence is lacking that PSA screening prevents prostate cancer deaths. Looking at the rate of interval cancerscancers diagnosed based on symptoms during the years between screening testsmay give an indication of how well a screening program is working.
Monique Roobol, Ph.D., of Erasmus Medical Centre in Rotterdam, The Netherlands, and his colleagues conducted a study to determine whether the time between PSA screenings influenced the occurence rate of prostate cancer. They analyzed data collected at two European medical centers that participated in the European Randomized Study of Screening for Prostate Cancer. At a center in Gothenburg, Sweden, 4,202 men were screened every two years, and in Rotterdam, The Netherlands, 13,301 men were screened every four years. The scientists compared both the number and characteristics of the interval prostate cancers diagnosed in these men. Serious, potentially life threatening interval cancers were analyzed separately.........
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August 28, 2007, 9:10 PM CT
A gene for metastasis
Colorectal cancer is one of the most prevalent cancers in the Western world. The tumor starts off as a polyp but then turns into an invasive and violent cancer, which often spreads to the liver. In an article recently reported in the journal Cancer Research, Prof. Avri Ben-Zeev and Dr. Nancy Gavert of the Weizmann Institutes Molecular Cell Biology Department reveal mechanisms that help this cancer metastasize.
In a majority of cases, colorectal cancer is initiated by changes in a key protein beta-catenin. One of the roles of this protein is to enter the cell nucleus and activate gene expression. But in colorectal and other cancers, beta-catenin over-accumulates in the cell and inappropriately activates genes, leading to cancer.
Surprisingly, one of the genes activated by beta-catenin, which had been previously detected in colorectal cancer cells by Ben-Zeevs group, codes for a receptor called L1-CAM. This receptor is a protein commonly found on nerve cells, where it plays a role in nerve cell recognition and motility. What is this receptor doing in cancer cells" Ben-Zeevs prior research had shown that L1-CAM is only expressed on certain cells located at the invasive front of the tumor tissue, hinting that it could be an important player in metastasis.
In this study, the researchers observed that colorectal cancer cells engineered to express the L1-CAM gene indeed spread to the liver, while those cells lacking L1-CAM did not.........
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August 28, 2007, 8:58 PM CT
Innovative Surgery For Sleep Apnea
Sleep disorder and ear, nose and throat specialists at Thomas Jefferson University are examining an innovative procedure to treat obstructive sleep apnea syndrome.
In the procedure, known as Genial Bone Advancement Trephine (GBAT), a small portion of the lower jaw which attaches to the tongue is moved forward, to pull the tongue away from the back of the airway, increasing the airway space. It is considered an option for patients when medications or a continuous positive airway pressure (C-PAP) device, which increases the supply of oxygen and reduces the work of breathing, have proven to be ineffective.
Even immediately after the procedure patients have an easier time breathing, noted Maurits Boon, M.D., Clinical Instructor in Otolaryngology-Head and Neck Surgery, Jefferson Medical College of Thomas Jefferson University. We have also found that in a select group of patients high blood pressure drops off.
This procedure is often employed as an adjunct to more conventional surgery and can be very effective at treating OSA (obstructive sleep apnea).
Sleep apnea is a breathing disorder characterized by brief interruptions of breathing during sleep. Obstructive sleep apnea occurs when there is collapse of upper airway structures that prevent normal airflow. This essentially, results in cessation of breathing with resultant decreases in oxygen in the blood stream. The consequence is that this pattern of breathing causes interruptions in the normal sleep cycle and makes it difficult to get a restful night of sleep.........
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August 28, 2007, 8:49 PM CT
Not all risk is created equal
A camper who chases a grizzly but won't risk unprotected sex. A sky diver afraid to stand up to the boss. New research shows that not all risk is created equal and people show a mixture of both risky and non-risky behaviors.
The survey also shows that men are significantly riskier than women overall.
The University of Michigan research refutes the standard theories of risk that group people as either risk-seeking or risk-avoiding, and suggests that we can have a mix of both risky and non-risky behavior depending on the type.
The study appears in the journal Evolutionary Psychology. Daniel Kruger, a research scientist at the U-M School of Public Health, and his colleagues X.T. Wang, University of South Dakota, and Andreas Wilke, UCLA, identified areas of risk taking (risk domains) based on the types of challenges that our ancestors faced during a number of thousands of years of human evolution.
"People are complex," said Kruger. "Just because somebody seems to be a big risk taker in one area doesnt mean they will take risks in all areas."
The types of risks identified include competition with other individuals; competition with other groups; mating and allocating resources for mate attraction; environmental risks (chasing a bear or skydiving); and fertility risks. The study showed that our tendencies for risk taking follow these different types of challenges.........
Posted by: JoAnn Read more Source
August 28, 2007, 8:43 PM CT
Hospital Practices Affect Long-Term Breastfeeding Success
Breast milk and breastfeeding are recognized to be the ideal choices of nutrition and feeding for infants. Breastfeeding is the normal method of feeding infants, and provides a number of benefits to both infants and mothers. In addition to receiving essential nutrients, breastfed infants have lower rates of ear infections, gastroenteritis, asthma, obesity and diabetes. Benefits for mothers include decreased occurence rate of breast and ovary cancer. National goals in the U.S. are a breastfeeding initiation rate of 75 percent (with an exclusive breastfeeding rate for the first 3 months of 60 percent), and continuation of 50 percent at 6 months of age (with 25 percent exclusively breastfeeding).
A new study in Birth: Issues in Perinatal Care suggests that implementing 5 breastfeeding-friendly practices in hospitals following birth can significantly improve long-term breastfeeding success. Nearly two-thirds of mothers who engaged in all 5 supportive practices were still breastfeeding 4 months after going home. The specific hospital practices include:.
- Initiating breastfeeding within 1 hour of delivery
- Keeping infants in the mother's hospital room
- Feeding infants only breast milk in the hospital; no supplementation of water or formula
- Prohibiting pacifier use in the hospital........
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August 27, 2007, 8:28 PM CT
Link Between Zinc And Macular Degeneration
A team of scientists, including three scientists at George Mason University, observed that the mineral zinc could play a role in the development of macular degeneration. In studying eye tissue samples, the researches observed that deposits, that are hallmarks of age-related macular degeneration (AMD), contain large amounts of zinc.
This finding, reported in the journal Experimental Eye Research, might be especially important because zinc supplements are widely given to patients to help boost weak immune systems. In addition, a 2001 study from the National Eye Institute observed that high doses of zinc supplements, combined with antioxidants, may postpone the progression to blindness.
AMD is a medical condition in which the macula, the place of central vision in the eye, experiences atrophy and in some cases bleeding. It is the primary cause of blindness in the elderly in Western society and approximately 13 million Americans suffer from the disease as per AMD Alliance International.
"Because earlier findings have shown that that zinc contributes to deposit formation in neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease, we were prompted to test the theory that zinc might be involved in deposit formation in AMD," said Mason professor of psychology, Jane Flinn.........
Posted by: Mike Read more Source
August 26, 2007, 10:58 AM CT
First Out-of-body Experience In Laboratory
The study participant sits in a chair wearing a pair of head-mounted video displays. These have two small screens over each eye, which show a live film recorded by two video cameras placed beside each other two metres behind the participant's head. The image from the left video camera is presented on the left-eye display and the image from the right camera on the right-eye display. The participant sees these as one 'stereoscopic' (3D) image, so they see their own back displayed from the perspective of someone sitting behind them. (Credit: Image courtesy of University College London)
A neuroscientist working at UCL (University College London) has devised the first experimental method to induce an out-of-body experience in healthy participants. In a paper published in Science, Dr Henrik Ehrsson, UCL Institute of Neurology, outlines the unique method by which the illusion is created and the implications of its discovery.
An out-of-body experience (OBE) is defined as the experience in which a person who is awake sees his or her own body from a location outside the physical body. OBEs have been reported in clinical conditions where brain function is compromised, such as stroke, epilepsy and drug abuse. They have also been reported in association with traumatic experiences such as car accidents. Around one in ten people claim to have had an OBE at some time in their lives.
Dr Ehrsson said: "Out-of-body experiences have fascinated mankind for millennia. Their existence has raised fundamental questions about the relationship between human consciousness and the body, and has been much discussed in theology, philosophy and psychology. Eventhough out-of-body experiences have been reported in many clinical conditions, the neuro-scientific basis of this phenomenon remains unclear.
"The invention of this illusion is important because it reveals the basic mechanism that produces the feeling of being inside the physical body. This represents a significant advance because the experience of one's own body as the centre of awareness is a fundamental aspect of self-consciousness".........
Posted by: JoAnn Read more Source
August 26, 2007, 10:43 AM CT
Clues To Obsessive-compulsive Disorder
SAPAP3 knockout mouse has a raw bald patch on its face from compulsive grooming behavior. (Credit: Guoping Feng, Ph.D., Duke University)
Mice born without a key brain protein compulsively groom their faces until they bleed and are afraid to venture out of the corner of their cages. When given a replacement dose of the protein in a specific region of the brain, or the drugs used to treat humans suffering from obsessive-compulsive disorder (OCD), a number of of these mice seem to get better.
Duke University Medical Center investigators, in their basic research into how individual brain cells communicate with each other, discovered serendipitously that mice with a genetic mutation that prevents their brain cells from producing one key protein exhibited OCD-like behavior.
The finding may have uncovered important clues about a possible mechanism for OCD, a debilitating psychiatric condition affecting up to 2 percent of the world's people.
The international team of researchers, led by Duke molecular geneticist Guoping Feng, Ph.D., reported its findings in the August 23 issue of the journal Nature. The research was supported by the National Institutes of Health, the McKnight Endowment Fund for Neuroscience, and the Hartwell Foundation.
"The mice that could not produce this protein exhibited behaviors similar to that of humans with OCD, a compulsive action coupled with increased anxiety," Feng said. "We obviously cannot talk to mice to find out what they are thinking, but these mutant mice clearly did things that looked like OCD".........
Posted by: JoAnn Read more Source
August 25, 2007, 6:27 AM CT
Novel Approach to Uncover Genetic Components of Aging
People who live to 100 or more are known to have just as a number of-and sometimes even more-harmful gene variants compared with younger people. Now, researchers at the Albert Einstein College of Medicine of Yeshiva University have discovered the secret behind this paradox: favorable "longevity" genes that protect very old people from the bad genes' harmful effects. The novel method used by the scientists could lead to new drugs to protect against age-related diseases.
"We hypothesized that people living to 100 and beyond must be buffered by genes that interact with disease-causing genes to negate their effects," says Dr. Aviv Bergman, a professor in the departments of pathology and neuroscience at Einstein and senior author of the study, which appears in the August 31 issue of PLoS Computational Biology.
To test this hypothesis, Dr. Bergman and colleagues examined individuals enrolled in Einstein's Longevity Genes Project, initiated in 1998 to investigate longevity genes in a selected population: Ashkenazi (Eastern European) Jews. They are descended from a founder group of just 30,000 or so people. So they are relatively genetically homogenous, which simplifies the challenge of associating traits (in this case, age-related diseases and longevity) with the genes that determine them.........
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August 25, 2007, 6:26 AM CT
Those student-athletes at risk for developing OSA
For most children and teens, the beginning of a new school year is just around the corner. Not only will they be hitting the books again after a three-month-long summer break, but a number of of them will also participate in after-school activities. More research is emerging that sheds light on a serious problem affecting student-athletes nationwide: the number of children and teens who are considered obese is rising dramatically. As per the American Academy of Sleep Medicine (AASM), obesity raises the risk of cardiovascular disease and other health problems, and also increases the likelihood of developing obstructive sleep apnea (OSA).
William Kohler, MD, medical director of the Florida Sleep Institute in Spring Hill, director of pediatric sleep services at University Community Hospital in Tampa, and an AASM pediatric sleep expert, warns that the health problems brought on by obesity, such as OSA, should serve as a wake-up call to not only student-athletes and their parents, but also to their instructors and coaching staff.
OSA can increase the risk for stroke, diabetes and cardiovascular disease, says Dr. Kohler. When the child or teen puts on weight, the throat can narrow, and anything which narrows the posterior pharynx can lead to the development of OSA. OSA is a serious disorder that can be harmful, or even fatal, if it is not recognized and treated.........
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