January 29, 2010, 8:16 AM CT

Are new genes always better?

Re-vegetation seems like a beneficial strategy for conserving and restoring damaged ecosystems, and using a variety of species can help increase biodiversity in these systems. But what are the risks involved with introducing seeds from other locations to plants located near the damaged site? Introduced populations often hybridize with the local populations from the same species, which can result in "polluting" neighboring populations with genes that are poorly adapted to local conditions. Long-term consequences of such "pollution" could negatively impact the survival of the existing native populations.

A recent article in the recent issue of the American Journal of Botany by Lisle Crmieux and his colleagues from the University of Fribourg in Switzerland (http://www.amjbot.org/cgi/content/full/97/1/94) looks at how gene flow from two distant populations and one local, but ecologically distinct, population affected a local population of Plantago lanceolata, a short-lived perennial herb. Seedling size, adult vegetative biomass, and estimated seed production were measured for two hybrid generations plus the first generation backcrossed with the local parents.

"We wanted to know whether the provenance of the seed material used in ecosystem restoration had an effect on the fitness of neighboring, locally adapted, populations," Crmieux said, "and not only on the success of the restored area itself"......... Posted by: Emily      Read more         Source

January 29, 2010, 8:12 AM CT

New treatment for malaria possible

Malaria causes more than two million deaths each year, but an expert multinational team battling the global spread of drug-resistant parasites has made a breakthrough in the search for better therapy. Better understanding of the make-up of these parasites and the way they reproduce has enabled an international team, led by John Dalton, a biochemist in McGill's Institute of Parasitology, to identify a plan of attack for the development of urgently needed new therapys.

Malaria parasites live inside our red blood cells and feed on proteins, breaking them down so that they can use the proceeds (amino acids) as building blocks for their own proteins. When they have reached a sufficient size they divide and burst out of the red cell and enter another, repeating the process until severe disease or death occurs. Dalton and colleagues observed that certain "digestive enzymes" in the parasites enable them to undertake this process. Importantly, the scientists have also now determined the three-dimensional structures of two enzymes and demonstrated how drugs can be designed to disable the enzymes.

"By blocking the action of these critical parasite enzymes, we have shown that the parasites can no longer survive within the human red blood cell," Dalton explains. The discovery would be reported in the Proceedings of the National Academy of Sciences, and is the result of collaboration including Australia's Queensland Institute of Medical Research, Monash University and the University of Western Sydney, Wroclaw University of Technology in Poland and the University of Virginia in the U.S. The team is putting their findings into action immediately and is already pursuing anti-malarial drug development......... Posted by: Emily      Read more         Source

January 28, 2010, 8:00 AM CT

Brain responses during anesthesia

The brains of people under anesthesia respond to stimuli as they do in the deepest part of sleep lending credence to a developing theory of consciousness and suggesting a new method to assess loss of consciousness in conditions such as coma.

Researchers at the University of Wisconsin School of Medicine and Public Health, led by brain researcher Fabio Ferrarelli, reported their findings in this week's edition of the Proceedings of the National Academy of Science

The group gave the anesthetic midazolam, usually used at lower doses in "conscious sedation" procedures such as colonoscopies, to volunteers.

Then they used transcranial magnetic stimulation (TMS), a noninvasive technique to stimulate the brain cortical neurons from the scalp, in combination with electroencephalography (EEG), which recorded the TMS-evoked brain responses. What they found is a pattern that looks much as it does when the brain is in deep, non-rapid eye movement (non-REM) sleep, another condition when consciousness fades.

Co-author and consciousness expert Giulio Tononi says that when the brain is unconscious it appears to lose the connectivity that underlies the coordinated, yet differentiated responses to electrical stimuli observed when the brain is awake or in REM sleep. The group's earlier studies demonstrated the differences between the sleeping and awake brain......... Posted by: Emily      Read more         Source

January 28, 2010, 7:57 AM CT

Research may find new treatment for aneurysms

New research findings from a team at the Providence Heart + Lung Institute at St. Paul's Hospital and the University of British Columbia (UBC) may lead to new therapy options for abdominal aortic aneurysms (AAA) a potentially fatal disease that currently has no pharmacological therapys.

An aortic aneurysm is a bulging of the aorta, the largest blood vessel in the body. If the aneurysm ruptures, it causes rapid blood loss and a high risk of death. About 75 per cent of all aortic aneurysms occur in the part of the aorta that is located in the abdomen, which supplies blood to the lower limbs.

Published in today's American Journal of Pathology, a study led by Dr. David Granville, a researcher with UBC and the Providence Heart + Lung Institute, reveals a novel therapeutic target for AAA that could have a major impact on the therapy of this disease.

Using experimental models of AAA, Dr. Granville and his team identified a protein-degrading enzyme called Granzyme B that is abundant in aneurysms. To determine whether Granzyme B was contributing to aneurysms, the enzyme was genetically knocked out.

"When we removed Granzyme B, we observed that it not only slowed the progression of aneurysms, but also markedly improved survival," says Dr. Granville. "This suggests that drugs designed specifically to target Granzyme B could be an effective means of treating aneurysms"......... Posted by: Emily      Read more         Source

January 28, 2010, 7:39 AM CT

Blood test can predict rheumatoid arthritis

Scientists from University Hospital in Umea, Sweden, have identified several cytokines, cytokine-related factors, and chemokines that increase significantly previous to rheumatoid arthritis (RA) disease onset. These findings confirm those of earlier studies which suggest that the risk of developing RA can be predicted and disease progression appears to be prevented. Complete findings of this study are reported in the recent issue of Arthritis & Rheumatism, a journal of the American College of Rheumatology.

Rheumatoid arthritis is a chronic autoimmune disease characterized by joint inflammation involving the synovial (lubricating fluid of the joints) tissue and eventually leading to destruction of cartilage and bone. The cause leading to disease development and progression is not completely understood, eventhough various cells of the immune system and of synovial origin are suggested to be involved. Numerous cytokines are expressed and are functionally active in the synovial tissue once the disease has developed. Now a research team led by Solbritt Rantap-Dahlqvist, M.D. has observed that several of these cytokine levels spike as much as several years previous to the development of arthritic symptoms.

An early and accurate diagnosis of RA is crucial. As per the American College of Rheumatology, RA can be difficult to diagnose because it appears to begin with only subtle symptoms, such as achy joints or early morning stiffness. A number of diseases including lupus, osteoarthritis and fibromyalgia, particularly early on, mimic the symptoms of RA making diagnosis more difficult. Studies have shown that people who receive early therapy for RA feel better sooner and more often, are more likely to lead an active life, and are less likely to experience the type of joint damage that leads to joint replacement......... Posted by: Emily      Read more         Source

January 28, 2010, 0:16 AM CT

Prenatal exposure to certain chemicals

A newly released study led by Mount Sinai scientists in collaboration with researchers from Cornell University and the U.S. Centers for Disease Control and Prevention, has found higher prenatal exposure to phthalatesmanmade chemicals that interfere with hormonal messagingto be connected with disruptive and problem behaviors in children between the ages of 4 and 9 years. The study, which is the first to examine the effects of prenatal phthalate exposure on child neurobehavioral development, will be published January 28, on the Environmental Health Perspectives website.

"There is increasing evidence that phthalate exposure is harmful to children at all stages of development," said Stephanie Engel, PhD, lead study author and Associate Professor of Preventive Medicine at Mount Sinai School of Medicine. "We found a striking pattern of associations between low molecular weight phthalates which are usually found in personal care products and disruptive childhood behaviors, such as aggressiveness and other conduct issues, and problems with attention. These same behavioral problems are usually found in children diagnosed with Attention-Deficit Hyperactivity Disorder (ADHD), Oppositional Defiant Disorder, or Conduct Disorder".

Phthalates are part of a group of chemicals known as endocrine disruptors, that interfere with the body's endocrine, or hormone system. They are a family of compounds found in a wide range of consumer products such as nail polishes, to increase their durability and reduce chips, and in cosmetics, perfumes, lotions and shampoos, to carry fragrance. Other phthalates are used to increase the flexibility and durability of plastics such as PVC, or included as coatings on medications or nutritional supplements to make them timed-release......... Posted by: Emily      Read more         Source

January 25, 2010, 8:13 AM CT

Autism Clusters in California

Two recent, separate publications identified regions with higher than expected numbers of autism cases - or clusters - in California. Using data collected by the California Department of Developmental Services (DDS) on 2.5 million births including almost 10,000 autism cases from 1996-2000, researchers at UC Davis1 uncovered several clusters of elevated risk for autism. Autism Speaks, the nation's largest autism science and advocacy organization, evaluated these studies and observed that the majority of these clusters were found to be strongly linked to higher parental education and, to a lesser extent, with parents of older ages. It is thought that parents with higher levels of education may have better access to the regional diagnostic and service centers in California, as the DDS relies on parents actively seeking services. Thus the distribution of cases is likely influenced by proximity to specialty research and service centers.

However, demographic factors, alone, may not explain the increased numbers of cases in these clusters. The authors propose that other factors, including environmental exposures, may play a role but warrant further investigation to understand their contribution to autism etiology.

"Examination of clusters can help us understand the factors that have led to in increase in autism prevalence over time," said Autism Speaks' Chief Science Officer, Geraldine Dawson, Ph.D......... Posted by: Emily      Read more         Source

January 25, 2010, 8:06 AM CT

Trauma patients safe from weekend effect

People who are in car crashes or suffer serious falls, gunshot or knife wounds and other injuries at nights or on weekends do not appear to be affected by the same medical care disparities as patients who suffer heart attacks, strokes, cardiac arrests and other time-sensitive illnesses during those "off hours," as per new research from the University of Pennsylvania School of Medicine. In contrast to previous, multi-hospital studies showing that patients treated for cardiac or neurological emergencies overnight and on weekends are more likely to experience complications and even die than those who come to the hospital on weekdays, the new pilot findings suggest that trauma patients are insulated from this so-called "weekend effect" tied to the time of day in which they're brought to the hospital.

The newly released study, which will be presented at the Eastern Association for the Surgery of Trauma on January 22, points to the trauma system's unique organization and staffing as a built-in protection for these critically injured patients. A regionalized system involving both ambulance and helicopter transport dictates that trauma patients be brought to facilities that meet strict requirements for round-the-clock staffing and capabilities for emergency medicine, radiology, surgery, and post-operative intensive care. One key differentiator from most other medical and surgical specialties - in which staffing and resources vary on nights and weekends - is that Level 1 trauma centers like the Hospital of the University of Pennsylvania, where the research was conducted, are mandatory to have an attending trauma surgeon immediately available 24 hours a day, seven days a week, 365 days a year......... Posted by: Emily      Read more         Source

Mon, 25 Jan 2010 05:36:10 GMT

Regenerative Medicine

TEDMED is one of the most prestigious and innovative medical conferences and it just started streaming presentations via videos. In the first video, streaming presentations via videos how he held his breath for 17 minutes. Now Anthony Atala talks about regenerative medicine:

Posted by: Bertalan      Read more     Source

January 19, 2010, 8:33 AM CT

Promising candidates for malaria vaccine

Walter and Eliza Hall Institute scientists have uncovered a group of proteins that could form the basis of an effective vaccine against malaria.

Presently there is no malaria vaccine available, and these new findings support the development of a vaccine against the blood-stage of malaria.

Malaria is an infection of blood cells and is transmitted by mosquitoes. The most common form of malaria is caused by the parasite Plasmodium falciparum Malaria parasites burrow into red blood cells by producing specific proteins. Once inside red blood cells, the parasites rapidly multiply, leading to massive numbers of parasites in the blood stream that can cause severe disease and death.

Dr James Beeson, Dr Freya Fowkes and Dr Jack Richards from the institute's Infection and Immunity division, along with Dr Julie Simpson from the University of Melbourne, have identified proteins produced by malaria parasites during the blood-stage that are effective at promoting immune responses that protect people from malaria illness.

Their findings are published recently in the international journal PLoS Medicine

Drs Fowkes and Beeson identified these proteins by reviewing and synthesising data from numerous scientific studies that had looked at the relationship between antibodies produced by the human immune system in response to malaria infection and the ability of these antibodies to protect against malaria......... Posted by: Emily      Read more         Source