December 30, 2010, 6:33 AM CT
Protein involved in cystic fibrosis
Principal investigator Neeraj Vij, Ph.D.
Credit: Johns Hopkins Children's Center
A team of Johns Hopkins Children's Center scientists has discovered that a protein involved in cystic fibrosis (CF) also regulates inflammation and cell death in emphysema and appears to be responsible for other chronic lung diseases.
The findings, published online in the recent issue of The Journal of Immunology
, pave the way toward new therapys to prevent lung damage caused by infections or cigarette smoke in emphysema.
The protein, called CFTR (cystic fibrosis transmembrane conductance regulator), is already well known for its role in transporting chloride in and out of cells. In CF, the protein's chloride-carrying ability is absent due to genetic mutations, resulting in the buildup of thick sticky mucus in the lungs, which causes lung infections and breathing problems.
But the new Hopkins study indicates that CFTR is involved in immune regulation and immune response on a far wider scale. The research � conducted in mice and using lung tissue from people with and without emphysema � shows that those with lung damage from emphysema had less CFTR on the cell surface and that changes in the level of CFTR corresponded directly to disease severity. Decreases in CFTR also corresponded to increased buildup in the lung cells of a fatty molecule called ceramide, a well-known trigger of inflammation and cell death. Thus, the scientists say, by regulating ceramide's inflammation-causing activity, CFTR may be a watchdog for inflammation and cell death.........
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December 30, 2010, 6:31 AM CT
Coma and general anesthesia
The brain under general anesthesia isn't "asleep" as surgery patients are often told -- it is placed into a state that is a reversible coma, as per three neuroresearchers who have published an extensive review of general anesthesia, sleep and coma, in the Dec. 30 issue of the New England Journal (NEJM)
This insight and others published in their review article could eventually lead to new approaches to general anesthesia and improved diagnosis and therapy for sleep abnormalities and emergence from coma.
The scientists explain that a fully anesthetized brain is much closer to the deeply unconscious low-brain activity seen in coma patients, than to a person asleep. Essentially, general anesthesia is a coma that is drug-induced, and, as a consequence, reversible. The states operate on different time scales -- general anesthesia in minutes to hours, and recovery from coma in hours to months to years, if ever. The study of emergence from general anesthesia and recovery from coma could help to better understand how both processes occur.
Understanding that these states have more in common with each other than differences -- that they represent a continuum of activity with common circuit mechanisms being engaged across the different processes of awakening from sleep or emerging from coma or general anesthesia -- "is very exciting, because it gives us new ways to understand each of these states," says co-author of study, Dr. Nicholas D. Schiff, a professor of neurology and neuroscience at Weill Cornell Medical College and a neurologist at NewYork-Presbyterian Hospital/Weill Cornell Medical Center. Co-authors of the study are Dr. Emery Brown of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard Medical School, and Dr. Ralph Lydic from the University of Michigan.........
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December 29, 2010, 6:34 AM CT
Breathalyzers for medical diagnostics
This image shows a new type of sensor for an advanced breath-analysis technology that rapidly diagnoses patients by detecting "biomarkers" in a person's respiration in real time. Researchers used a template made of micron-size polymer particles and coated them with much smaller metal oxide nanoparticles. Using nanoparticle-coated microparticles instead of a flat surface allows researchers to increase the porosity of the sensor films, increasing the "active sensing surface area" to improve sensitivity. (Purdue University and NIST)
Scientists have overcome a fundamental obstacle in developing breath-analysis technology to rapidly diagnose patients by detecting chemical compounds called "biomarkers" in a person's respiration in real time.
The scientists demonstrated their approach is capable of rapidly detecting biomarkers in the parts per billion to parts per million range, at least 100 times better than prior breath-analysis technologies, said Carlos Martinez, an assistant professor of materials engineering at Purdue who is working with scientists at the National Institute of Standards and Technology.
"People have been working in this area for about 30 years but have not been able to detect low enough concentrations in real time," he said. "We solved that problem with the materials we developed, and we are now focusing on how to be very specific, how to distinguish particular biomarkers".
The technology works by detecting changes in electrical resistance or conductance as gases pass over sensors built on top of "microhotplates," tiny heating devices on electronic chips. Detecting biomarkers provides a record of a patient's health profile, indicating the possible presence of cancer and other diseases.
"We are talking about creating an inexpensive, rapid way of collecting diagnostic information about a patient," Martinez said. "It might say, 'there is a certain percentage that you are metabolizing a specific compound indicative of this type of cancer,' and then additional, more complex tests could be conducted to confirm the diagnosis."........
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December 29, 2010, 6:24 AM CT
Key interaction in hepatitis C virus
Researchers from the Florida campus of The Scripps Research Institute have identified a molecular interaction between a structural hepatitis C virus protein (HCV) and a protein critical to viral replication. This new finding strongly suggests a novel method of inhibiting the production of the virus and a potential new therapeutic target for hepatitis C drug development.
The study was reported in the January 2010 issue (Volume 92, Part 1) of the Journal of General Virology
These new data underline the essential role of the viral protein known as "core" as a primary organizer of the infectious HCV particle assembly and support a new molecular understanding of the formation of the viral particle itself.
"While our finding that the HCV core interacts with the non-structural helicase protein was not totally unexpected, this had not really been confirmed until this study," said Scripps Florida Professor Donny Strosberg, who led the study. "But the most exciting part is that small molecule inhibitors of dimerization [the joining of two identical subunits] of core actually inhibit interaction between core and helicase, thus possibly preventing production of an infectious viral particle".
A Viral Plague
Hepatitis C virus infects between 130 and 170 million people worldwide and is the cause of an epidemic of liver cirrhosis and cancer. Because current HCV therapys are only partially effective, many alternative molecular mechanisms are actively being pursued as possible drug targets.........
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December 29, 2010, 6:06 AM CT
Poor response to anti-anemia drug predicts higher risk
Testing of patients with diabetes, kidney disease and anemia who don't respond to an anti-anemia drug treatment has demonstrated a higher risk of cardiovascular disease or death. The testing was led by Dr. Robert Toto and was administered by Tammy Lightfoot, clinical research manager.
Credit: UT Southwestern Medical Center
Patients with diabetes, kidney disease and anemia who don't respond to therapy with an anti-anemia drug have a higher risk of cardiovascular disease or death, scientists at UT Southwestern Medical Center have found.
The results suggest that testing such patients' responsiveness to the drug and keeping blood iron levels a little low might reduce their risk, said Dr. Robert Toto, professor of internal medicine and clinical sciences and a senior author of the study, which appeared in the New England Journal (NEJM)
"These patients mandatory higher doses and ended up having lower hemoglobin anyway," Dr. Toto said. "The results of this study might lead us in directions that can help".
The results were an unexpected finding of a study on darbepoetin alpha, which stimulates the production of red blood cells to counteract anemia. The drug, manufactured by Amgen, is sold under the name Aranesp.
The study, called the Trial to Reduce Cardiovascular Events with Aranesp Therapy (TREAT) showed that darbepoetin alpha works no better than a placebo for improving cardiovascular and kidney outcomes, but it did lower the risk for blood transfusion and resulted in modest improvement in patient-reported outcomes among people with diabetes, kidney disease and anemia. However, people receiving darbepoetin alpha had nearly a twofold higher risk for stroke. Cancer deaths were also higher among people receiving the drug.........
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December 25, 2010, 10:44 AM CT
Electronic medical records not always linked to better care
Use of electronic health records by hospitals across the United States has had only a limited effect on improving the quality of medical care, as per a new RAND Corporation study.
Studying a wide mix of hospitals nationally, scientists observed that hospitals with basic electronic health records demonstrated a significantly higher increase in quality of care for patients being treated for heart failure.
However, similar gains were not noted among hospitals that upgraded to advanced electronic health records, and hospitals with electronic health records did not have higher quality care among patients treated for heart attack or pneumonia.
The findings, published online by the American Journal of Managed Care
, are part of a growing body of evidence suggesting that new methods should be developed to measure the impact of health information technology on the quality of hospital care.
"The lurking question has been whether we are examining the right measures to truly test the effectiveness of health information technology," said Spencer S. Jones, the study's main author and an information scientist at RAND, a nonprofit research organization. "Our existing tools are probably not the ones we need going forward to adequately track the nation's investment in health information technology".........
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December 25, 2010, 10:32 AM CT
Eat your veggies, reward your kidneys
Phosphorous levels plummet in kidney disease patients who stick to a vegetarian diet, as per a research studyappearing in an upcoming issue of the Clinical Journal of the American Society Nephrology
(CJASN). The results suggest that eating vegetables rather than meat can help kidney disease patients avoid accumulating toxic levels of this mineral in their bodies.
Individuals with kidney disease cannot adequately rid the body of phosphorus, which is found in dietary proteins and is a common food additive. Kidney disease patients must limit their phosphorous intake, as high levels of the mineral can lead to heart disease and death. While medical guidelines recommend low phosphorus diets for patients with chronic kidney disease (CKD), phosphorus content is not listed on food labels.
Sharon Moe, MD (Indiana University School of Medicine and Roudebush Veterans' Affairs Medical Center) and her colleagues studied the effects of vegetarian and meat-based diets on phosphorous levels in nine patients with CKD. Patients followed a vegetarian or meat-based diet for one week, followed by the opposite diet two-to four- weeks later. Blood and urine tests were performed at the end of each week on both diets.
Despite equivalent protein and phosphorus concentrations in the two diets, patients had lower blood phosphorus levels and decreased phosphorus excretion in the urine when they were on the vegetarian diet compared with the meat-based diet. While the researchers did not determine the reason for this difference, a grain-based diet has a lower phosphate-to-protein ratio and much of the phosphate is in the form of phytate, which is not absorbed in humans.........
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December 24, 2010, 1:38 PM CT
You are what your father ate
Researchers at the University of Massachusetts Medical School and the University of Texas at Austin have uncovered evidence that environmental influences experienced by a father can be passed down to the next generation, "reprogramming" how genes function in offspring. A newly released study published this week in Cell shows that environmental cues�in this case, diet�influence genes in mammals from one generation to the next, evidence that until now has been sparse. These insights, coupled with prior human epidemiological studies, suggest that paternal environmental effects may play a more important role in complex diseases such as diabetes and heart disease than previously believed.
"Knowing what your parents were doing before you were conceived is turning out to be important in determining what disease risk factors you appears to be carrying," said Oliver J. Rando, MD, PhD, associate professor of biochemistry & molecular pharmacology at UMMS and principal investigator for the study, which details how paternal diet can increase production of cholesterol synthesis genes in first-generation offspring.
The human genome is often described as the set of instructions that govern the development and functioning of life. It's not surprising, then, that most contemporary genetic research focuses on understanding and cataloging how mutations and changes to our DNA�the basis of those "instructions"�cause disease and impact health. Many recent studies, however, have begun to draw attention to the role epigenetic inheritance � inherited changes in gene expression caused by mechanisms other than changes in the underlying DNA sequence � may play in a host of illnesses. "A major and underappreciated aspect of what is transmitted from parent to child is ancestral environment," said Dr. Rando. "Our findings suggest there are a number of ways that parents can 'tell' their children things".........
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December 24, 2010, 1:29 PM CT
Fat cells become useful stem cells
Two studies appearing in the current issue.
of Cell Transplantation
19(10) discuss stem cells derived from adipose (fat) cells and their potential use in plastic surgery and tissue reconstruction. The studies are now freely available on-line at http://www.ingentaconnect.com/content/cog/ct/.
Adipose-derived stem cells maintain their "stemness" and could be useful for cell-based therapies.
A team of scientists from several institutions in Italy isolated and characterized adult fat cell-derived stem cells from patients undergoing lipoaspiration (surgical removal of fat deposits) in order to investigate the ability of the fat cells to maintain their stem cell characteristics in in vitro cultures to the point where once transplanted they could aid in tissue regeneration.
As per the study's corresponding authors Dr. Stefami Bucher of the San Gallicano Institute (Rome) and Dr. Rita Falcioni of the Regina Elena Cancer Institute (Rome), adipose tissues share several biological properties with bone marrow, they can be found in abundance, they can be obtained from patients undergoing noninvasive lipoaspirate procedures, and they have the potential to be useful in a range of therapeutic applications.
"The use of lipoaspirate as filling material is a powerful technique for tissue repair in plastic surgery," said Dr. Falcioni. "Increasingly, it is used in oncology to repair tissue damaged by surgical therapys, such as mastectomy. The use of purified adipose-derived stem cells might improve this surgical procedure by shortening the time to achieve esthetic results and thereby improving patient quality of life."........
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December 21, 2010, 6:38 AM CT
Robotic surgery for head and neck cancer
Less-invasive robotic surgery for upper airway and digestive track cancerous tumors is as effective as other minimally invasive surgical techniques based on patient function and survival, as per University of Alabama at Birmingham researchers.
Head and neck squamous cell carcinomas account for about 4 percent of cancerous tumors diagnosed in the United States each year. Currently the standard minimally invasive surgery for these tumors is transoral laser microsurgery.
Prior studies have shown that the robotic surgery was better for patients to regain the ability to swallow, a common and serious side effect, but never looked at cure rate. Manguson wanted to know if you could achieve function and get rid of the cancer at the same time. This study, published Dec. 20, 2010, in the Archives of Otolaryngology - Head & Neck Surgery,
showed you could.
UAB otolaryngologist and the study's senior author J. Scott Magnuson, M.D., and his colleagues from UAB and the Mayo Clinic looked at 89 patients with various stages of head and neck squamous cell carcinomas whose primary tumor was resected using the da Vinci Robot. All of the patients were monitored during their hospital stay and up to 33 months after surgery.
"The overall two-year survival rate for these patients was 86.3 percent, which is comparable to the standard therapy," Magnuson, also a scientist in the UAB Comprehensive Cancer Center, said. "Those with earlier-stage tumors appeared to have slightly better recurrence-free survival than those with later stages, but it was not statistically significant".........
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