Last week during the ‘Vaccines for Biothreats and Emerging and Neglected Diseases Symposium’ in Galveston TX, USA, the Elsevier journal Vaccine released a supplement dedicated to vaccines for biodefense. This publication provides a comprehensive, state-of-the-art overview on vaccines that have been developed against a diverse group of human and veterinary pathogens, including Bacillus anthracis, smallpox, and blue tongue.

Biodefense has traditionally been associated with defense against biological warfare agents with an emphasis on military applications. However, the events of October 2001 involving envelopes containing anthrax spores sent through the US Postal Service radically changed our thinking about biodefense. We now recognize the need for biodefense to protect both civilian and military populations against biothreat agents. As research continues to develop biodefense countermeasures, it is clear that vaccines are a critical component of the portfolio to control biothreats.

In their editorial in the supplement, the US Guest Editors Alan Barrett (University of Texas Medial Branch), Shan Lu (University of Massachusetts), and Greg Poland (Mayo Clinic Vaccine Research Group) state that, “the progress in development of vaccines for biothreat agents has been remarkable due to the combined efforts of academia, biotechnology companies, larger pharma, governments, and regulatory authorities, and it is our hope that this supplement may serve as a milestone for this process and a useful reference for people interested in knowing the current status of biodefense vaccine development”.

The supplement was launched at the 3rd in a series of symposia around the theme of, ‘The Changing Landscape of Vaccine Development’, organized by the Sealy Center for Vaccine Development at the University of Texas Medical Branch in Galveston TX, USA in conjunction with the James W. McLaughlin Fellowship Fund.

The symposium Co-Chair and Co-Guest Editor of the Vaccine Supplement, Alan Barrett judged the conference a great success and said: “By focusing on the progression of biodefense vaccine development from bench to bedside the symposium very successfully brought together experts from industry, academia and government to discuss the latest developments in discovery, preclinical development, clinical trials and vaccine acceptance”.

Source: Floris de Hon

Elsevier

Gene silencing techniques and induced pluripotent stem cell technology are among the cutting-edge approaches to Parkinson’s drug development funded through The Michael J. Fox Foundation’s Rapid Response Innovation Awards 2008. As part of its mission to drive transformative treatments and a cure for PD, the Foundation has awarded $1.1 million for 15 high-risk, high-reward Parkinson’s disease research projects under the initiative in the first half of the year. Applications are still being accepted, and a total of $2 million in Rapid Response awards is expected by year’s end.

Rapid Response helps keep new and novel approaches to Parkinson’s disease flowing into the drug development pipeline by allowing researchers to pursue their most exciting ideas in real time. The Foundation accepts Rapid Response proposals on a rolling basis with no deadline, and funding decisions are made within six weeks of application. Awards of up to $75,000 are available for one-year basic, preclinical or clinical research projects in any Parkinson’s-relevant arena. The program has met with an enthusiastic response from the research community, both within Parkinson’s disease and beyond, since it was first launched in January 2007.

“Rapid Response infuses capital quickly into exciting new ideas that could open up important new avenues of inquiry for Parkinson’s disease,” said Katie Hood, CEO of The Michael J. Fox Foundation. “Our goal is to provide the funding needed to further ‘build the case’ for these new concepts, developing the data required before other traditional funding sources can step in.”

The program’s application process and funding criteria emphasize speed and novelty. Funded projects typically are strong ideas being tested for the first time. Unlike other Foundation initiatives, Rapid Response allows for the submission of applications at any time of year. There is no pre-proposal triage stage, and the standard MJFF application has been shortened to three pages. Additionally, postdoctoral researchers are permitted to apply as principal investigators provided the head of their lab serves as administrative PI.

Among the potentially high-impact Rapid Response projects funded so far this year:
Asa Abeliovich, MD, PhD, of Columbia University is working to determine whether a gene silencing technique using microRNAs – short, noncoding molecules of RNA – can be effective in reducing alpha-synuclein, a protein whose aggregation, or clumping, in the brain is a hallmark of Parkinson’s pathology.

Jian Feng, PhD, of SUNY-Buffalo, and Patrick Alfryn Lewis, PhD, of the Institute of Neurology (London, UK) and John A. Hardy, PhD, University College London (London, UK) are conducting two separate investigations using newly discovered induced pluripotent stem cell (iPS) technology to shed greater light on the Parkinson’s-implicated genes parkin and LRRK2. Using iPS, the teams are engineering stem cells from skin cells, then using these engineered stem cells to generate human dopamine neurons with or without mutations in the respective genes. Both projects seek to characterize disease mechanisms set off by genetic mutations and to create new models for testing therapeutic approaches that could prevent these events from occurring.

Rahul Srinivasan, MBBS, PhD, and Henry A. Lester, PhD, of the California Institute of Technology are working to better understand epidemiological findings that have consistently shown smoking may protect against PD. The researchers hope to elucidate the mechanisms by which nicotine may protect dopamine neurons through development and validation of a screening test for small molecules that could increase nicotine receptor expression in the brain.

Marcus Unger, MD, and Wolfgang Oertel, MD, of Phillips University (Marburg, Germany) want to find better treatments for the digestive problems that dramatically affect Parkinson’s patients’ quality of life, as well as test the Braak hypothesis, which posits that Parkinson’s disease progresses through the body and to the brain in a series of stages starting in the gastrointestinal system. They are examining a possible link between constipation and Lewy body pathology in the gastric lining of people with PD.

Founded in 2000, The Michael J. Fox Foundation for Parkinson’s Research is dedicated to ensuring the development of a cure for Parkinson’s disease within the coming decade through an aggressively funded research agenda. The Foundation has funded $126 million in research to date.

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Source: Holly Barkhymer

The Michael J. Fox Foundation for Parkinson’s Research

Add university research to the long list of human activities contributing to global warming.

HervГ© Philippe, a UniversitГ© de MontrГ©al professor of biochemistry, is a committed environmentalist who found that his own research produces 44 tonnes of CO2 per year. The average American citizen produces 20 tonnes.

“I did my PhD on nucleotide sequencing in the hope of advancing our knowledge of biodiversity, but I never thought that the research itself could have a negative impact on biodiversity,” he said, during a recent biology department symposium.

Philippe has a well-established international reputation for his work on phylogeny and according to his calculations his computers produce 19 tonnes of CO2 per year, the air conditioning in the laboratory produces 10 tonnes of CO2 per year, and transport from one meeting to another produces 15 tonnes of CO2 per year.

Philippe doesn’t believe in the myth that technology is the solution. “In 1973, that type of rhetoric already existed,” he says. “But environmental problems have gone from bad to worse. In Canada, for instance, oil consumption is 1.7 times greater despite better technology.”

It will have taken 200 years of oil exploitation to dry up the reserves that took 200 million years to build. “This fact has been known for 50 years but we’ve done nothing about it. By viewing oil as an unlimited resource we are making a tremendous mistake.”

He doesn’t believe in one magical solution, but rather in transformations adapted to each area. For universities, he recommends having less frequent international conferences, increasing the use of videoconferences, avoiding research on well explored topics, reducing publications and evaluating the amount of CO2 produced by research projects.

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On the web:

About the UniversitГ© de MontrГ©al: umontreal/english/index.htm.

For more information:

Sylvain-Jacques Desjardins
International press attachГ©
UniversitГ© de MontrГ©al

Source: HervГ© Philippe

University of Montreal

Contrary to conventional medical wisdom, a new study by NYU Langone Medical Center researchers shows that healthy elderly patients with severe to profound hearing loss can undergo a surgical procedure to receive cochlear implants with minimal risk. “Due to concerns about the effects of general anesthesia, many elderly people with hearing loss are not receiving the implants which can significantly improve their hearing and quality of life,” according to Anil Lalwani, M.D., Mendik Foundation Professor of Otolaryngology and Chairman of the Department of Otolaryngology at NYU School of Medicine and a study co-author. “The elderly are often incorrectly considered too fragile for this life transforming technology that can deliver them from a world of silence and loneliness to a world of hearing and engagement,” says Dr. Lalwani. The new study is published in the February issue of the journal The Laryngoscope.

The National Institute on Aging estimates that 30 % of Americans between ages 65 and 74 have hearing difficulty and that number increases to 50 percent in people 85 and older. In about 10% of the elderly, the impairment is so severe that conventional hearing aids provide little benefit. The inability to communicate interferes greatly with daily living and can lead to cognitive impairment, personality changes, depression, reduced functional status and social isolation.

The researchers conducted a retrospective chart review of 70 patients over 70 years of age who received cochlear implants under general anesthesia at NYU Langone Medical Center between 1984 and 2007. The patients were divided into risk groups and intraoperative and postoperative anesthesia-related complications were identified. Most patients tolerated the procedure and there was no long-term morbidity or mortality related to the surgery or anesthesia.

The researchers concluded that general anesthesia is well tolerated by elderly patients undergoing cochlear implantation. Any pre – existing medical condition is a better predictor of intraoperative and postoperative complication than age alone, they observed. Jung T. Kim, M.D. Vice chairman of the Department of Anesthesiology at NYU School of Medicine and a study co-author said “As seniors embrace a healthy and active lifestyle, it is important that age alone should not deter a person from having surgery that could potentially improve their quality of life.”

About NYU LANGONE MEDICAL CENTER

One of the world’s premier academic medical institutions for more than 167 years, NYU Langone Medical Center continues to be a leader in patient care, physician education and scientific research. NYU Langone Medical Center is internationally renowned for excellence in areas such as cardiovascular disease, orthopaedics, pediatrics, skin care, neurosurgery, urology, cancer care, imaging, rehabilitation medicine, plastic surgery, minimally invasive surgery, transplant surgery, infertility, and women’s health.

New York University Langone Medical Center
1 Park Ave.
New York
NY 10016
United States
med.nyu.edu

Boston Scientific
Corporation (NYSE: BSX) today announced it has received clearance from the
U.S. Food and Drug Administration (FDA) to market its FilterWire EZ(TM)
Embolic Protection System for use in carotid artery stenting (CAS)
procedures. The device was cleared by the FDA in August 2004 for use in
coronary saphenous vein graft (SVG) interventions and is currently the
market-leading embolic protection device for carotid artery stenting
procedures outside the U.S.

The FilterWire EZ System is designed to efficiently capture plaque and
other embolic material that may dislodge during stent implantation and
prevent it from traveling into the microvasculature where it could pose an
increased risk for stroke or heart attack. The device features simplified
filter sizing — one size can be placed in vessel diameters between 3.5 mm
and 5.5 mm — and is designed for easy preparation, delivery and retrieval.
The safety and performance of the FilterWire EZ System was evaluated in the
CABERNET Trial in conjunction with the recently approved NexStent(R)
Carotid Stent and Monorail(R) Delivery System. With the new carotid
indication, the FilterWire EZ Embolic Protection System can now be used in
the U.S. to treat patients with carotid artery disease who are at high risk
for surgery.

“We are pleased to now offer U.S. physicians the benefits of the
FilterWire EZ System — the world’s leading embolic protection system — in
conjunction with the NexStent Carotid Stent to offer a less-invasive
alternative to treating carotid artery disease and help reduce the
devastating effects of stroke,” said John Pedersen, President of Boston
Scientific’s Peripheral Interventions business. “With its second cleared
indication, the FilterWire EZ System offers innovation and versatility to
treat a variety of lesions and cases seen in every day practice.”

The carotid arteries are located on either side of the neck and are the
main conduit through which blood flows from the heart to the brain. Carotid
artery disease occurs when plaque forms in these arteries, causing them to
harden and narrow, impeding blood flow and increasing the risk of stroke in
affected patients. Until recently, the only option for opening the vessels
was to perform carotid endarterectomy, a surgical procedure involving a
vertical incision in the neck and artery and removal of the plaque from the
vessel walls. Carotid artery stenting is a less-invasive procedure in which
a stent-bearing catheter is guided to the affected area of the carotid
arteries. The stent is designed to be placed at the site of the blockage,
where it expands and forces the walls of the arteries open, restoring the
blood flow.

SVG disease occurs in patients who have previously had coronary artery
bypass graft (CABG) surgery in which a vessel harvested from the patient’s
leg is surgically attached to the arteries of the heart. Blood is then
redirected around the blocked artery, increasing blood flow to the heart.
SVGs are more fragile and unpredictable than native coronary arteries,
creating a challenging treatment situation and an increased need for
embolic protection.

Boston Scientific is a worldwide developer, manufacturer and marketer
of medical devices whose products are used in a broad range of
interventional medical specialties. For more information, please visit:
bostonscientific/.

This press release contains forward-looking statements. Boston
Scientific wishes to caution the reader of this press release that actual
results may differ from those discussed in the forward-looking statements
and may be adversely affected by, among other things, risks associated with
new product development and commercialization, clinical trials,
intellectual property, regulatory approvals, competitive offerings,
integration of acquired companies, Boston Scientific’s overall business
strategy, and other factors described in Boston Scientific’s filings with
the Securities and Exchange Commission.

Boston Scientific Corporation
bostonscientific/

Cardax Pharmaceuticals, Inc., a privately held pharmaceutical company headquartered in Honolulu, Hawaii, announced positive results presented at the Arteriosclerosis, Thrombosis and Vascular Biology 2011 Scientific Sessions from two animal proof-of-concept studies designed to assess the effectiveness of its lead proprietary prodrug of astaxanthin, CDX-085, in cardiovascular-related disease pathology. In LDLr-/- mice, the novel anti-inflammatory drug CDX-085 significantly reduced both aortic arch atherosclerosis and total cholesterol levels in a dose-dependent manner. Additionally, in a study employing apoE-/- mice, a significant and dose-dependent, 50-72% reduction in circulating triglyceride levels was observed in groups treated with increasing doses of CDX-085.

Oxidative stress and inflammation are key promoters of atherosclerosis and myocardial damage. The astaxanthin prodrug CDX-085 is a novel and highly bioavailable carotenoid antioxidant that has been observed to protect LDL particles against oxidation and to reduce arterial thrombosis. Related proprietary Cardax prodrugs have also been shown to decrease recurrent thrombosis and reperfusion injury in experimental models of thrombosis and myocardial infarction.

“It should be no surprise that the active drug astaxanthin, which has been observed to have a significant impact on TNF-О± and the NF-ОєB pathway, should affect both quantitative and qualitative aspects of inflammation-associated lipid dysfunction,” notes lead investigator, Sotirios Tsimikas, MD from the University of California San Diego. “We are encouraged that these animal proof-of-concept data demonstrate that CDX-085 may be a promising oral therapy for the treatment of hypertriglyceridemia and other dyslipidemic disorders,” said Fredric Pashkow, MD, Executive Vice President and Chief Medical Officer, Cardax Pharmaceuticals.

This series of experiments represents a portion of the extensive animal proof-of-concept studies performed using the CDX-085 drug candidate, and the biological data are consistent with recently reported results from randomized clinical trials conducted in Japan using the active drug of CDX-085, astaxanthin.

Presentation Title: The Effect of an Oral Astaxanthin Prodrug (CDX-085) on Lipoprotein Levels and Progression of Atherosclerosis In LDLR-/- and ApoE-/- Mice
Author Information: Sung Kee Ryu, Jennifer Pattison, Univ California San Diego, La Jolla, CA; Timothy J King, Cardax Pharmaceuticals, Honolulu, HI; Sotirios Tsimikas, Univ California San Diego, La Jolla, CA

Source:
Cardax Pharmaceuticals, Inc.

Researchers at the Gladstone Institute of Cardiovascular Disease (GICD) have discovered a key switch that makes stem cells turn into the type of muscle cells that reside in the wall of blood vessels. The same switch might be used in the future to limit growth of vascular muscle cells that cause narrowing of arteries leading to heart attacks and strokes, limit formation of blood vessels that feed cancers, or make new blood vessels for organs that are not getting enough blood flow.

In a study published in the current issue of the journal Nature, the researchers found that a tiny RNA molecule, called microRNA-145 (miR-145), not only had all the information necessary to turn a stem cell into a vascular smooth muscle cell (VSMC), but could also affect VSMCs in the adult artery. VSMCs have the unique property that they can start dividing when an artery is injured or during atherosclerosis, ultimately causing narrowing of the vessel leading to occlusion. miR-145 and its sister microRNA, miR-143, work together to stop the pathologic division of VSMCs. In the setting of vessel disease, their activity was turned down, allowing the VSMCs to divide and clog up the artery.

microRNAs are small RNA molecules that do not make protein, but instead affect that amount of protein synthesized by the cell from their target mRNAs – the blueprints for translating the genetic code into proteins. miR-145 and miR-143 together controlled the synthesis of a network of “master regulators” that control VSMCs, and thereby were able to function as a central “switch” for the behavior of these important cells.

“The ability of miR-145 to efficiently direct the cell fate of vascular smooth muscle cells from stem cells represents the power of these tiny microRNAs to exert major effects on cells,” said Deepak Srivastava, MD, GICD director and senior author of the study. “We hope that we can use this knowledge to control when the body makes or does not make new blood vessels,” he added.

Previously, GICD researchers had shown that miR-143 is highly enriched when embryonic stem cells turned into cardiac stem cells. Here they found that miR-143 and miR-145 were both present as the heart was forming in mice, but became localized to the smooth muscle of blood vessels and of the gut after birth.

Further analysis revealed that miR-143 and miR-145 are directly controlled by a protein called myocardin, which itself is sufficient to “reprogram” an adult non-muscle cell into a VSMC. Furthermore, the activation of these microRNAs by myocardin was a necessary event for myocardin to induce the VSMC fate. In one type of stem cell, miR-145 by itself was enough to completely push the stem cell into a functioning VSMC.

These findings suggested that miR-143 and miR-145 are involved in the switch between the differentiation and proliferation of VSMCs – and thus contribute to vessel narrowing in heart disease. In a mouse model of this switch generated by collaborator Joseph Miano, PhD, a professor at the Cardiovascular Research Institute of the University of Rochester, expression of miR-143 and miR-145 was markedly reduced in injured arteries containing proliferating, less differentiated smooth muscle cells. Interestingly, miR-145 mRNA was also reduced to almost undetectable levels in atherosclerotic blood vessels with thickened walls.

“miR-145 was necessary and sufficient for differentiation of VSMCs, so it is possible that restoring its activity could prevent the vessel narrowing in atherosclerosis,” said Kimberly Cordes, PhD, a postdoctoral fellow in the Srivastava lab and lead author of the study.

Since the effects of miRNAs depend on their mRNA targets, the researchers looked for mRNA targets of miR-143 and miR-145. They found that miR-143 and miR-145 cooperate in targeting a network of transcription factors, including Klf4, myocardin, and Elk-1, to promote the differentiation and repress proliferation of smooth muscle cells. “The multiple targets we identified for miR-143 and miR-145 reveal an elegant mechanism by which these miRNAs promote differentiation and simultaneously repress proliferation of VSMCs” said Dr. Srivastava.

The targets miR-145 and miR-143 regulate are not only major regulators of VSMCs, but also control whether cells divide excessively in conditions such as cancer. According to Dr. Cordes, “the downregulation of miR-145 in numerous cancers and our findings in this study raise the possibility that miR-145 could function as a pro-differentiation factor in cancers also and could be a new therapeutic target.”

“Our findings in this study offer insights into regulatory mechanisms that govern the differentiation and proliferation of smooth muscle,” said Dr. Srivastava. “They have fundamental implications for the treatment of vessel diseases like atherosclerosis and also may be important for cancer.”

The research was supported the National Institutes of Health, the California Institute for Regenerative Medicine (CIRM) and the American Heart Association. Other authors on the study include Neil T. Sheehy, Mark White, Emily Berry, Sarah U. Morton, Alecia N. Muth, and Kathryn N. Ivey of Gladstone and UCSF and Ting-Hein Lee and Joseph M. Miano of the University of Rochester.

Deepak Srivastava’s primary affiliation is with the Gladstone Institute of Cardiovascular Disease, where he is director and where his laboratory is located and all of his research is conducted. He is also a professor of medicine in the Departments of Pediatrics and Biochemistry and Biophysics at the University of California, San Francisco.

Source:
Valerie Tucker

Gladstone Institutes

Despite improvements in the ability to diagnose malaria, these diagnostic tests are often underused in Zambia, and patients with negative test results are often prescribed anti-malaria medications, according to a study in the May 23/30 issue of JAMA, a theme issue on malaria.

The recent introduction of the effective but expensive artemisinin-based (a type of medication) combination therapy for malaria throughout Africa has led to renewed interest in improving the accuracy of diagnosis. The use of rapid antigen-detection diagnostic tests (RDTs) has been proposed as an approach for reducing overtreatment of malaria. The most widely used method to confirm a diagnosis of malaria is microscopy, according to background information in the article.

Davidson H. Hamer, M.D., of the Boston University School of Public Health, Boston, and colleagues from the Zambian Ministry of Health, the Kenyan Medical Research Institute and University of Oxford, assessed the association between use of microscopy and RDT and the prescription of antimalarials in Zambia. The researchers conducted a survey, carried out between March and May 2006, of 104 government and mission health facilities in four districts in Zambia. At each facility, data were collected during one working day on ill outpatients treated at the facility.

An equipment survey in the four districts revealed that 17 percent of the 104 health facilities had functional microscopy; 63 percent had RDTs. Overall, 73 percent of health facilities had at least 1 type of malaria diagnostics available.

Of the 1,717 patients (of all ages) with fever (suspected malaria), 27.8 percent treated in health facilities with malaria diagnostics were tested and 44.6 percent had positive test results. Of patients with negative blood smear results, 58.4 percent were prescribed an antimalarials, as were 35.5 percent of those with a negative RDT result. Most patients with fever (72.6 percent) did not have any diagnostic procedure performed. Antimalarials were prescribed to 66 percent of these patients. About half of this group received artemether-lumefantrine (an artemisinin-based combination therapy).

In facilities with artemether-lumefantrine in stock, this antimalarial was prescribed to a large proportion of patients with fever with a positive diagnostic test result, but also to some with a negative diagnostic test result (blood smear, 30.4 percent; RDT, 26.7 percent).

“RDTs have been proposed as a cost-effective approach to reducing overtreatment of malaria; under current practice in Zambia, however, their use will not achieve this goal,” the authors write.

“Given the widespread increase of artemisinin-based combination therapy in sub-Saharan Africa for management of uncomplicated malaria, there is a need to limit inappropriate use of these expensive new combinations. The increasing body of evidence that a substantial proportion of febrile patients do not have malaria, especially in low to moderate transmission zones, emphasizes the need to educate health center staff on the rational use of artemisinin-based combination therapy, which will require strengthening the availability of malaria diagnostics and enhancing quality control measures so that health care providers will have confidence in the test results.”

“The RDT training program in Zambia needs to be restructured such that trainees are provided with clear instructions about how to respond to a negative test result. Without taking these steps, we may rapidly be confronted with widespread resistance of P falciparum to artemisinin-based combination therapy, and the lifespan of these highly effective new therapies will be reduced,” the authors conclude.

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(JAMA. 2007;297:2227-2231)

Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

Contact: Lisa Brown
JAMA and Archives Journals

A group of “professional couch potatoes,” as one researcher described them, has proven that even moderate exercise – in this case walking at one’s own pace for 40 minutes three times a week – can enhance the connectivity of important brain circuits, combat declines in brain function associated with aging and increase performance on cognitive tasks.

The study, in Frontiers in Aging Neuroscience, followed 65 adults, aged 59 to 80, who joined a walking group or stretching and toning group for a year. All of the participants were sedentary before the study, reporting less than two episodes of physical activity lasting 30 minutes or more in the previous six months. The researchers also measured brain activity in 32 younger (18- to 35-year-old) adults.

Rather than focusing on specific brain structures, the study looked at activity in brain regions that function together as networks.

“Almost nothing in the brain gets done by one area – it’s more of a circuit,” said University of Illinois psychology professor and Beckman Institute Director Art Kramer, who led the study with kinesiology and community health professor Edward McAuley and doctoral student Michelle Voss. “These networks can become more or less connected. In general, as we get older, they become less connected, so we were interested in the effects of fitness on connectivity of brain networks that show the most dysfunction with age.”

Neuroscientists have identified several distinct brain circuits. Perhaps the most intriguing is the default mode network (DMN), which dominates brain activity when a person is least engaged with the outside world – either passively observing something or simply daydreaming.

Previous studies found that a loss of coordination in the DMN is a common symptom of aging and in extreme cases can be a marker of disease, Voss said.

“For example, people with Alzheimer’s disease tend to have less activity in the default mode network and they tend to have less connectivity,” she said. Low connectivity means that the different parts of the circuit are not operating in sync. Like poorly trained athletes on a rowing team, the brain regions that make up the circuit lack coordination and so do not function at optimal efficiency or speed, Voss said.

In a healthy young brain, activity in the DMN quickly diminishes when a person engages in an activity that requires focus on the external environment. Older people, people with Alzheimer’s disease and those who are schizophrenic have more difficulty “down-regulating” the DMN so that other brain networks can come to the fore, Kramer said.

A recent study by Kramer, Voss and their colleagues found that older adults who are more fit tend to have better connectivity in specific regions of the DMN than their sedentary peers. Those with more connectivity in the DMN also tend to be better at planning, prioritizing, strategizing and multi-tasking.

The new study used functional magnetic resonance imaging (fMRI) to determine whether aerobic activity increased connectivity in the DMN or other brain networks. The researchers measured participants’ brain connectivity and performance on cognitive tasks at the beginning of the study, at six months and after a year of either walking or toning and stretching.

At the end of the year, DMN connectivity was significantly improved in the brains of the older walkers, but not in the stretching and toning group, the researchers report.

The walkers also had increased connectivity in parts of another brain circuit (the fronto-executive network, which aids in the performance of complex tasks) and they did significantly better on cognitive tests than their toning and stretching peers.

Previous studies have found that aerobic exercise can enhance the function of specific brain structures, Kramer said. This study shows that even moderate aerobic exercise also improves the coordination of important brain networks.

“The higher the connectivity, the better the performance on some of these cognitive tasks, especially the ones we call executive control tasks – things like planning, scheduling, dealing with ambiguity, working memory and multitasking,” Kramer said. These are the very skills that tend to decline with aging, he said.

This study was supported by the National Institute on Aging at the National Institutes of Health.

Source:
University of Illinois at Urbana-Champaign

Anthony S. Fauci, M.D., will speak during the opening session of ICAAC/IDSA 2008, a joint meeting of the American Society for Microbiology and the Infectious Diseases Society of America, in Washington, DC. His keynote lecture at 4:30 p.m. on Saturday, Oct. 25, is titled Global Health and Infectious Diseases: A Look to the Future. Dr. Fauci is director of the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.

Among many global health challenges, infectious diseases remain among the most problematic, accounting for about one quarter of all deaths globally, and nearly two-thirds of deaths in sub-Saharan Africa. Dr. Fauci will discuss progress–and remaining challenges–in the fight against major infectious causes of death and disability such as HIV/AIDS, malaria, tuberculosis and drug-resistant microbes. He also will discuss how conceptual and technological progress in fields such as genomics and nanotechnology has invigorated infectious disease research. These advances also are contributing to exciting studies on the ecology of human disease, including the Human Microbiome Project, which is exploring how the billions of bacteria that inhabit our bodies contribute to health and illness.

Other NIAID scientists are scheduled to present findings during the four-day meeting as well. The range of topics covered reflects the broad scope of NIAID’s research efforts aimed at better understanding, treating and preventing infectious and immune-mediated diseases.
Noroviruses, the highly contagious viruses that cause the episodes of acute gastroenteritis also known as winter vomiting disease (Kim Green, Ph.D.)

The role of gut-dwelling commensal bacteria in producing the symptoms of Crohn’s disease, a chronic inflammatory disease of the intestines (Warren Strober, M.D.)

Antibiotic-resistant bacterial infections caused by Staphylococcus epidermidis (Michael Otto, Ph.D.) and Staphylococcus aureus (Frank DeLeo, Ph.D.)

Finding ways to treat primary immunodeficiencies, inherited conditions in which immune function is impaired (Steve Holland, M.D.)

Containing Ebola virus, for which there is currently no vaccine or specific treatment (Gary Nabel, M.D., Ph.D.)

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Additional information about the 2008 ICAAC/IDSA Joint Meeting is available at icaacidsa2008/. The meeting will be held at the Walter E. Washington Convention Center in Washington, DC.

NIAID conducts and supports research–at NIH, throughout the United States, and worldwide–to study the causes of infectious and immune-mediated diseases, and to develop better means of preventing, diagnosing and treating these illnesses. News releases, fact sheets and other NIAID-related materials are available on the NIAID Web site at niaid.nih/.

The National Institutes of Health (NIH)–The Nation’s Medical Research Agency–includes 27 Institutes and Centers and is a component of the U. S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical and translational medical research, and it investigates the causes, treatments and cures for both common and rare diseases. For more information about NIH and its programs, visit nih/.

News releases, fact sheets and other NIAID-related materials are available on the NIAID Web site at niaid.nih/.

Source: NIAID Office of Communications

NIH/National Institute of Allergy and Infectious Diseases