September 20, 2010, 7:12 AM CT
Better marker for breast cancer
A scanning electron micrograph of porous silica microspheres filled with perfluoropentane vapor. This new material, invented at the University of California -- San Diego, is visible with Doppler ultrasound, sticks to breast tissue and can mark the location of tumors too small to be seen or felt during surgery.
Credit: Paul Martinez, UCSD
A new material could help surgeons more accurately locate breast cancers, reduce the need for second surgeries and minimize pre-surgical discomfort for patients. Microscopic gas-filled spheres of silica, a porous glass, can mark the location of early-stage tumors to show their position using ultrasound imaging in the operating room.
A team of chemists, radiologists and surgeons at the University of California, San Diego, created the new material, which they describe in a forthcoming issue of the journal MedChemComm
The X-rays used to make mammograms reveal calcium deposits linked to breast cancer even in tumors too small to be felt. But surgeons can't use X-rays while operating. Instead, radiologists place guide wires into tumors hours or even the day before surgery. The wires don't mark depth well and can shift. Patients find them both uncomfortable and unsettling.
As an alternative, the scientists created spheres of silica and filled them with perfluoropentane, a gas that has been used before in short-lived contrast materials for medical imaging. The rigid silica shells help the new material last longer.
"These little gas-filled microbubbles stick to human breast tissue for days and can be seen with ultrasound," said William Trogler, professor chemistry. "If doctors placed them in early stage breast cancer, which is difficult to see during surgery, they could help surgeons remove all of it in the first operation".........
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September 20, 2010, 7:10 AM CT
Childhood viral infection may be a cause of obesity
Jeffrey B. Schwimmer, M.D.
Credit: UC San Diego
The emerging idea that obesity may have an infectious origin gets new support in a cross-sectional study by University of California, San Diego School of Medicine scientists who observed that children exposed to a particular strain of adenovirus were significantly more likely to be obese.
The study would be reported in the September 20 online edition of the journal Pediatrics
September is National Childhood Obesity Awareness Month.
Jeffrey B. Schwimmer, MD, associate professor of clinical pediatrics at UC San Diego, and his colleagues examined 124 children, ages 8 to 18, for the presence of antibodies specific to adenovirus 36 (AD36), one of more than 50 strains of adenovirus known to infect humans and cause a variety of respiratory, gastrointestinal and other infections. AD36 is the only human adenovirus currently associated with human obesity.
Slightly more than half of the children in the study (67) were considered obese, based on a Body Mass Index or BMI in the 95th percentile or greater. The scientists detected neutralizing antibodies specific to AD36 in 19 of the children (15 percent). The majority of these AD36-positive children (78 percent) were obese, with AD36 antibodies much more frequent in obese children (15 of 67) than in non-obese children (4 of 57).........
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September 16, 2010, 8:50 AM CT
Grab a glass of milk when you're on diet
Now there's a new reason to grab a glass of milk when you're on diet, suggests a new study published in the American Journal of Clinical Nutrition
In a 2-year weight loss study, milk drinkers had an advantage over those who skipped the milk. Israeli researchers found that adults who drank the most milk (nearly 2 glasses per day) and had the highest vitamin D levels at 6 months, lost more weight after 2 years than those who had little or no milk or milk products -- nearly 12 pounds weight loss, on average.
Researchers also found that each additional 6-ounce serving of milk or milk products (about 3/4 of a glass of milk) was associated with 10 pounds successful weight loss above the average, at 6 months.
More than 300 overweight or at risk men and women ages 40 65 participated in the study following low-fat, Mediterranean or low-carb diets for 2 years. Regardless of diet, researchers found participants with the highest dairy calcium intake 6 months into the study (averaging about 580mg per day the amount in nearly 2 glasses of milk) lost about 12 pounds at the end of the 2 years, compared to about 7 pounds for those with the lowest dairy calcium intake (averaging about 150mg, or about half of a glass).
Beyond calcium, the researchers also found that vitamin D levels independently affected weight loss success and in line with previous research, milk and milk products were the top contributors to vitamin D in the diets of the study participants.........
Posted by: JoAnn Read more Source
September 16, 2010, 8:47 AM CT
How bacteria acquire immunity
In a newly released study this week, Rice University researchers bring the latest tools of computational biology to bear in examining how the processes of natural selection and evolution influence the way bacteria acquire immunity from disease.
The study is available online from Physical Review Letters
It builds upon a main discoveries made possible by molecular genetics in the past decade -- the revelation that bacteria and similar single-celled organisms have an acquired immune system.
"From a purely scientific perspective, this research is teaching us things we couldn't have imagined just a few years ago, but there's an applied interest in this work as well," said Michael Deem, the John W. Cox Professor in Biochemical and Genetic Engineering and professor of physics and astronomy at Rice. "It is believed, for instance, that the bacterial immune system uses a process akin to RNA interference to silence the disease genes it recognizes, and biotechnology companies may find it useful to develop this as a tool for silencing particular genes".
The newly released study by Deem and graduate student Jiankui He focused on a portion of the bacterial genome called the "CRISPR," which stands for "clustered regularly interspaced short palindromic repeats." The CRISPR contain two types of DNA sequences. One type -- short, repeating patterns that first attracted scientific interest -- is what led to the CRISPR name. But researchers more recently learned that the second type -- originally thought of as DNA "spacers" between the repeats -- is what the organism uses to recognize disease.........
Posted by: Mark Read more Source
September 16, 2010, 8:37 AM CT
Brain protein levels and Alzheimer's disease
This is Eliezer Masliah, M.D., of the University of California - San Diego.
Credit: UCSD School of Medicine
Elevated levels of a growth protein in the brains of Alzheimer's disease (AD) patients is associated with impaired neurogenesis, the process by which new neurons are generated, say scientists at the University of California, San Diego in today's edition of The Journal of Neuroscience
Eliezer Masliah, MD, professor of neurosciences and pathology in the UC San Diego School of Medicine and his colleagues report that increased levels of BMP6 part of a family of bone morphogenetic proteins involved in cell signaling and growth were found in the brains of Alzheimer's patients and in mouse models of the disease.
BMP6 is primarily known to be involved in bone growth and the proliferation of non-neuronal glial cells in developing embryos. Its purpose in adult brains is less clear. "As a growth factor, it might initially be expressed for protective effect, a response to accumulating amyloid plaque proteins in Alzheimer's patients," said first author Leslie Crews, a post-doctoral researcher in Masliah's lab.
But too much BMP6 may be increasingly detrimental. Scientists observed that levels of BMP6 grew in step with the progression of Alzheimer's disease. "In early stages of AD, there was less protein than there was in later, more advanced stages," said Crews.........
Posted by: Daniel Read more Source
September 11, 2010, 9:21 AM CT
World's first transcontinental anesthesia
This shows a video-real stream in Montreal from patient monitoring in Pisa.
Credit: Credit: Dept. of Anesthesia, McGill University, Montreal.
Videoconferences appears to be known for putting people to sleep, but never like this. Dr. Thomas Hemmerling and his team of McGill's Department of Anesthesia achieved a world first on August 30, 2010, when they treated patients undergoing thyroid gland surgery in Italy remotely from Montreal. The approach is part of new technological advancements, known as 'Teleanesthesia', and it involves a team of engineers, scientists and anesthesiologists who will ultimately apply the drugs intravenously which are then controlled remotely through an automated system.
"The practice has obvious applications in countries with a significant number of people living in remote areas, like Canada, where specialists may not be available on site," Hemmerling said. "It could also be used for teaching purposes, allowing the resident to perform tasks without the physical presence of a tutor, thus increasing his or her confidence level".
Four strategically placed video cameras monitored every aspect of patient care in Pisa, Italy, in real time. Ventilation parameters (such as the patient's breathing rate), vital signs (ECG, heart rate, oxygen saturation) and live images of the surgery are monitored by each camera, with the fourth used for special purposes. A remote computer station ('anesthesia cockpit') is required, as is a workstation that handles the audio-video link between the two centres. "Obviously, local anesthesiologists can override the process at any time," Hemmerling explained. Previous to the operation, an evaluation of the patient's airway and medical history is also performed via video-conferencing.........
Posted by: Sue Read more Source
September 11, 2010, 9:14 AM CT
Sizing Up Vaccines
Vaccination is the most important public health strategy for protection from serious illnesses such as whooping cough and polio. But this strategy relies on having an ample stockpile. Researchers have found that how these stockpiles are built and deployed has different implications for public health.
A creative version of a classic engineering technique may improve decisions about building and using supplies of important pediatric vaccines, potentially leading to lower public health costs and healthier children.
The United States maintains a six-month supply of common pediatric vaccines to ensure protection from deadly diseases, such as the flu, polio, and diphtheria, despite interruptions in vaccine production. The stockpiles must be replenished as the vaccines are used or expire, and, because the manufacture of vaccines is a laborious and unreliable process, health officials must place orders for new vaccines up to a year in advance.
Scientists at the University of Illinois at Urbana-Champaign (UIUC) and the Rochester Institute of Technology (RIT) have developed a mathematical framework to better understand the implications of vaccine stockpile levels through evidence-based engineering principles. Industrial engineers Sheldon Jacobson of UIUC and Ruben Proaño of RIT, who specialize in operations research, and Janet Jokela, a specialist in public health and infectious diseases at UIUC, published this work in the online edition of the November 2010 Journal of Industrial and Management Optimization.
Deciding how a number of pediatric vaccine doses to order from year to year is no simple task. As per the researchers, "The decision must balance several objectives that sometimes conflict." These include: minimizing the impact of vaccine shortages, maintaining or increasing vaccine coverage, and minimizing vaccine costs (including costs from unused vaccine).........
Posted by: Mark Read more Source
September 11, 2010, 8:56 AM CT
Neural proteins linked to autism disorders
An international team of scientists, led by scientists at the University of California, San Diego, has identified misfolding and other molecular anomalies in a key brain protein linked to autism spectrum disorders.
Palmer Taylor, associate vice chancellor for Health Sciences at UC San Diego and dean of the Skaggs School of Pharmacy and Pharmaceutical Sciences, and his colleagues report in the September 10 issue of the Journal of Biological Chemistry
that misfolding of a protein called neuroligin-3, due to gene mutations, results in trafficking deficiencies that may lead to abnormal communications between neurons.
Genetic misfolding of neuroligins is thought to prevent normal formation and function of neuronal synapses. The gene mutation has been documented in patients with autism.
"It makes sense that there's a connection," said Taylor. "The neuroligins are involved in maintaining neuronal synapses and their malfunction is likely to affect a neurodevelopmental disease".
Neuroligins are post-synaptic proteins that help glue together neurons at synapses by connecting with pre-synaptic protein partners called neurexins. They are part of a larger family of alpha-beta-hydrolase fold proteins that includes a number of molecules with diverse catalytic, adhesion and secretory functions.........
Posted by: JoAnn Read more Source
September 11, 2010, 8:55 AM CT
Alzheimer protein's function revealed
In people with Alzheimer's, the brain becomes riddled with clumps of protein, forming what are known as amyloid plaques. Now, a report appearing in the September 17th print issue of Cell
appears to have found a function for the amyloid precursor protein (APP for short) that yields the prime ingredient in those plaques.
It turns out that APP is an iron oxidase whose job it is to convert iron from an unsafe form to a safe one for transport or storage. When APP fails to function properly, as it does in Alzheimer's disease, iron levels inside neurons mount to toxic levels.
"This opens a big window on Alzheimer's disease and iron metabolism," said Ashley Bush of The Mental Health Research Institute, University of Melbourne.
"Eventhough people have attributed several important physiological roles to APP," added Jack Rogers of Harvard Medical School, "this now gives us an idea of what this critical protein does to underpin its role in iron metabolism".
In fact, there were some clues. Some years ago, the scientists discovered that the RNA template for the APP protein includes an iron-responsive element. When iron levels rise, cells ramp up their APP production.
But amyloid in and of itself doesn't really explain what goes wrong in the Alzheimer's brain. "There has been a lot of attention on amyloid, but it seems it is not a simple matter of amyloid as the sole culprit," Bush said. For one thing, trials of drugs designed to target and clear amyloid plaques haven't worked as intended.........
Posted by: Daniel Read more Source
September 9, 2010, 6:47 AM CT
Restaurant menu labeling legislation
The government's role in improving the nation's nutrition is now firmly established with nutritional labeling for restaurant meals now mandated across the United States as part of HR 3590 Patient Protection and Affordable Health Care Act. An article in the recent issue of the Journal of the American Dietetic Association
explains how state and municipal labeling laws developed and how the new national law will supersede these and replace them with a uniform standard. It also addresses the American Dietetic Association's (ADA's) involvement and how these new regulations will impact registered dietitians (RDs) and dietetic technicians, registered (DTRs) as well as consumers.
With enactment of the new law and detailed regulations to be issued by the Food and Drug Administration, restaurants and food vendors with 20 or more outlets will be mandatory to post calories on menus, menu boards (including drive-through) and food display tags, with additional nutrient information (fat, saturated fat, carbohydrates, sodium, protein, and fiber) available in writing upon request. Calorie posting requirements will also apply to vending machines managed by companies that operate at least 20 machines.
This new legislation will ensure that restaurant diners are provided with tools to make informed, healthful choices regarding the foods they consume outside the home. The article provides insights into how this law may work, including recommendations for how RDs may play a critical part in a successful implementation of this national standard.........
Posted by: JoAnn Read more Source