Health articles

April 24, 2009, 5:01 AM CT

Cattle genome sequencing milestone promises health benefits

The landmark sequencing of the domestic cattle genome, reported today in the journal Science, could lead to important new findings about health and nutrition, a participating Michigan State University researcher said.

Theresa Casey, a research assistant professor in the Department of Animal Science, joined 300 colleagues around the world in a six-year project to complete, annotate and analyze the bovine genome sequence.

The species Bos taurus includes 22,000 genes, 80 percent of which are shared with humans. Humans, scientists conclude, are closer to the bovine sequence than to those of mice or rats, which are far more usually used as research subjects.

That realization could open new vistas for human health research.

The new data are particularly important given the economic and nutritional importance of cattle to humans, said Casey, whose specialty is study of lactation and mammary gland biology. Focusing on genes that regulate milk synthesis in the cow, she also co-authored a companion report appearing in the journal Genome Biology discussing how the bovine lactation genome sheds light on the evolution of mammalian milk.

"We think that milk evolved primarily as an immune function," she said, due in part to cow milk's anti-microbial properties......... Posted by: Rose      Read more         Source

April 24, 2009, 4:59 AM CT

New mediator of smoking recruits

Freiburg, Gera number of Current research suggests that smoking increases the production of osteopontin in the lungs, which contributes to the development of smoking-related lung disease. The related report by Prasse et al, "Essential role of osteopontin in smoking-related interstitial lung diseases," appears in the May 2009 issue of The American Journal of Pathology

Nearly one billion people worldwide smoke tobacco products. Long-term exposure to compounds found in smoke can lead to both cardiovascular and lung disease. Eventhough lung exposure to cigarette smoke leads to immune cell recruitment and tissue fibrosis, how cigarette smoke causes these changes is largely unknown.

To determine if osteopontin, a molecule that attracts immune cells, mediates cell recruitment in smokers, Prasse et al compared osteopontin levels from smokers with different types of lung diseases, healthy smokers, and healthy non-smokers. They found high levels of osteopontin expression in patients with interstitial lung disease, whereas healthy smokers had lower levels, and healthy non-smokers produced no osteopontin. Osteopontin expression could be stimulated directly by nicotine therapy. In addition, expressing osteopontin in rat lung resulted in recruitment of immune cells, resulting in symptoms similar to smoking-related interstitial lung diseases. These results indicate that osteopontin appears to be pathogenic in smoking-initiated lung disease......... Posted by: Jessica      Read more         Source

April 7, 2009, 5:10 AM CT

Altered immune response to smoking

Smoking cigarettes is not only the principle cause of chronic obstructive pulmonary disease (COPD), but it may change the body's immune responses to bacteria that usually cause exacerbations of the disease, as per new research in a mouse model.

"It is well established that smoking is the main risk factor for COPD. But our research also suggests that cigarette smoke substantially changes the immune response to bacteria, which means that patients with COPD who smoke are weakening their body's ability to deal effectively with bacterial invaders. This may cause even further progression of the disease," said Martin Stmpfli, Ph.D., an associate professor at McMaster University, the principle investigator of the study.

"We wanted to see whether and how cigarette smoke would change the inflammatory response to the bacteria that is the culprit behind a number of COPD exacerbations, nontypeable Haemophilus influenzae or NTHI".

Their results were reported in the second issue of April of the American Journal of Respiratory and Critical Care Medicine

Dr. Stmpfli and his colleagues tested the effects of cigarette smoke exposure on inflammation and immune response in mice that were exposed to cigarette smoke twice daily five days a week for either eight weeks or four days then challenged with an intranasal inoculation of NTHI. The cigarette smoke exposure roughly approximated that of an "average" human smoker (within the limitations of a model with differing metabolic processes.) Control mice were not exposed to cigarette smoke, but were inoculated with NTHI as were the cigarette smoke-exposed mice......... Posted by: Rose      Read more         Source

March 24, 2009, 6:34 AM CT

Genetic machinery for thiostrepton synthesis

Scientists at the Georgia Institute of Technology have identified the genetic machinery responsible for synthesizing thiostrepton, a powerful antibiotic produced by certain bacteria. Though effective against the dangerous MRSA (methicillin-resistant Staphylococcus aureus) and vancomycin-resistant enterococci, thiostrepton currently has only limited applications in humans because it is not water soluble.

Identification of the gene cluster responsible for producing thiostrepton sets the stage for genetic manipulations that could make the drug more useful by improving its water solubility, potentially providing a new tool in the high-stakes battle against bacteria. Beyond the possible medical applications, the research produced a scientific surprise: thiostrepton is derived from a genetically encoded peptide that undergoes no fewer than 19 different modifications, one of the most complex such processes known and a surprising capability for a single-celled bacterium.

"We are interested in making derivatives of this peptide drug that retain their potency and are efficiently processed by biochemical machinery," said Wendy L. Kelly, an assistant professor in Georgia Tech's School of Chemistry and Biochemistry and the Parker Petit Institute for Bioengineering and Bioscience. "We want to put in substitutions to the genetic machinery that may create a more water soluble analog and could potentially be used for development of a new class of antibacterial agent"......... Posted by: Rose      Read more         Source

December 6, 2008, 3:57 PM CT

Interventions that may alter the course of epilepsy

Early diagnosis and therapy that quickly achieves seizure freedom with nominal side effects is the key goal to epilepsy management. Three studies highlighted at the AES annual meeting address this goal from different vantage points:

• The course to seizure freedom? Identifying factors that may change the landscape of epilepsy therapy to improve patients' quality of life.
• New EEG technology that may facilitate accurate seizure screening by non-specialists in urgent care settings.
• Task force report on disparity in standards for Epilepsy Monitoring Units amidst rise in number of epilepsy therapy centers.

"Each clue we uncover in understanding epilepsy and how to suppress the disruptions it causes for those affected takes us closer to the goal of successfully treating this chronic condition. Data from this year's meeting lead us towards answers about characteristics we can focus on to more effectively diagnose and treat epilepsy," said Dennis D. Spencer, M.D., AES President, Harvey and Kate Cushing Professor and Chair of Neurosurgery, Yale University School of Medicine. "This is particularly critical because we know that an estimated one-third of seizures are not controlled with existing therapies".



Epilepsy Patients Achieving Seizure Freedom More Quickly, As per New Analysis........ Posted by: Rose      Read more         Source

December 6, 2008, 3:55 PM CT

First childhood obesity symposium

On Tuesday, November 25, 2008, the Obesity Institute at Children's National Medical Center gathered experts from a number of disciplines to share ideas, failures and successes, and the future promise of prevention and intervention strategies to fight childhood obesity, both in the District of Columbia and nationwide.

Through the Obesity Institute, Children's National seeks to reduce childhood obesity using a multidisciplinary approach that draws upon our experts from throughout Children's National, as well as research, clinical, policy, and advocacy partners region.

"There is no single cause for the increase in childhood obesity, but certainly high fat diets and lack of exercise are contributing factors," said Denice Cora-Bramble, MD, MBA, executive director of the Goldberg Center for Community Pediatric Health at Children's National. "Likewise, there is no single answer to systematically solving the problem. But the upward trend, particularly here in the District, demands that we develop effective interventions faster."

Children's Obesity Institute tackles these issues from all angles. The Institute's multidisciplinary approach allows for a better understanding of the causes and barriers around this disorder, analyzing them from the laboratories that study the genetics to the community interventions impacting family lifestyles. Scientists, pediatricians, psychology experts, psychiatry experts, and a number of others presented their most recent efforts to uncover the underlying risk factors for childhood obesity and the earlier onset of type 2 diabetes......... Posted by: Rose      Read more         Source

November 19, 2008, 8:36 PM CT

Report finds extensive use of illicit alcohol

The consumption of illicit or noncommercial alcohol is widespread in a number of countries worldwide and contributes significantly to the global burden of disease, as per a new report released recently by the International Center for Alcohol Policies (ICAP). The report focuses on the use of noncommercial alcohol, defined as traditional beverages produced for home consumption or limited local trade and counterfeit or unregistered products, in three regions: sub-Saharan Africa, southern Asia, and central and eastern Europe.

The report, Noncommercial Alcohol in Three Regions, finds a significant portion of alcohol produced, sold, and consumed around the world is not reflected in official statistics. As per the World Health Organization (WHO), noncommercial drinks account for a significant portion of alcohol consumed in the three regions.

"The extensive use of noncommercial alcohol around the world has detrimental and far-reaching effects on consumers, government and the industry," says Marcus Grant, President of ICAP. "In a number of countries, this largely illicit alcohol has harmful effects on society because of the lack of meaningful controls".

Highlights from the report include:

• In Ukraine, unrecorded or noncommercial alcohol consumption exceeds recorded alcohol consumption (10.5 vs. 6.09 per capita consumption in liters, respectively).........
  
  
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October 29, 2008, 10:20 PM CT

Obesity, other health problems delay MS diagnosis

People with pre-existing medical conditions, such as obesity, and vascular problems such as diabetes, hypertension or high cholesterol, may experience a delay in being diagnosed with multiple sclerosis (MS), or experience an increase in severity of the disease at diagnosis, as per a research studyreported in the October 29, 2008, online issue of Neurology, the medical journal of the American Academy of Neurology.

"Our study suggests that doctors who treat people with chronic diseases should not attribute new neurological symptoms such as numbness and tingling to existing conditions without careful consideration," said study author Ruth Ann Marrie, MD, PhD, of the University of Manitoba in Winnipeg, Canada, and member of the American Academy of Neurology.

For the study, scientists examined the records of 8,983 people who had been diagnosed with MS. Of those, 2,375 were further classified as having mild, moderate or severe disability within two years of diagnosis. This well-characterized group was asked about pre-existing health conditions, their smoking status and weight history.

The study observed that it took one to 10 years longer for people who were obese, smoked, or had physical or mental health conditions to be diagnosed with MS in comparison to people without such conditions. The study also observed that the more medical problems a person with MS had, the more severe the disease had become by the time they were diagnosed......... Posted by: Rose      Read more         Source

October 14, 2008, 8:23 PM CT

Larger labs report kidney function routinely

Labs that conduct the highest number of routine blood tests are more likely than others to report estimated glomerular filtration rate (eGFR), an important measure of kidney function that can identify early kidney disease, as per a survey funded by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health (NIH). The work is published in the recent issue of the American Journal of Kidney Diseases

"We are encouraged to find that a number of labs are routinely reporting eGFR, allowing earlier diagnosis and therapy of kidney disease, " said NIH Director Elias A. Zerhouni, M.D. "But the survey illustrates the need to continue NIH efforts to promote automatic reporting of eGFR by all labs so that more people can benefit from earlier diagnosis."

The survey observed that more than 86 percent of the highest-volume independent labs (those in the top 5 percent) and more than 55 percent of all labs in the top quarter of high-volume labs report eGFR, in contrast to only 24 percent of low-volume labs (those in the bottom quarter). The survey demonstrates room for improvement in making eGFR readily available to primary care providers who could be treating early chronic kidney disease primarily caused by diabetes and hypertension and possibly reducing their patients' risk for kidney failure, which results in the need for dialysis or a kidney transplant......... Posted by: Rose      Read more         Source

September 24, 2008, 9:30 PM CT

Mapping the neuron-behavior link in Rett Syndrome

A link between certain behaviors and the lack of the protein linked to Rett Syndrome a devastating autism spectrum disorder demonstrates the importance of MeCP2 (the protein) and reveals never-before recognized functions linked to aggression and obesity, said scientists at Baylor College of Medicine in a report in the current issue of the journal Neuron.

"This protein is critical for the proper function of majority of neurons," said Dr. Huda Y. Zoghbi, a BCM professor of pediatrics, neurology, neuroscience, molecular and human genetics and a Howard Hughes Medical Institute investigator who is senior author on the paper. Zoghbi and her laboratory discovered the Rett gene.

Rett Syndrome affects between 1 in 10,000 females who express a wide variety of symptoms, most of them neurological.

"Observe a girl with Rett Syndrome and you will see that she has most of the neurological symptoms you are familiar with," Zoghbi said. "There are movement problems, balance problems, tremor, seizures, autism, learning and memory problems, anxiety and even more".

Girls with Rett Syndrome lack MeCP2 (found on the X chromosome) in as a number of as 50 percent of their neurons. The severity and breadth of symptoms they experience depend on the percentage of neurons that lack the protein......... Posted by: Rose      Read more         Source

September 16, 2008, 10:23 PM CT

Looking vs. seeing

The superior colliculus has long been thought of as a rapid orienting center of the brain that allows the eyes and head to turn swiftly either toward or away from the sights and sounds in our environment. Now a team of researchers at the Salk Institute for Biological Studies has shown that the superior colliculus does more than send out motor control commands to eye and neck muscles.

Two complementary studies, both led by Richard Krauzlis, Ph.D., an associate professor in the Systems Neurobiology Laboratory at the Salk Institute, have revealed that the superior colliculus performs supervisory functions in addition to the motor control it has long been known for. The results are reported in the Aug. 6 and Sept. 17 issues of the Journal of Neuroscience.

"Beyond its classic role in motor control, the primate superior colliculus signals to other brain areas the location of behaviorally relevant visual objects by providing a 'neural pointer' to these objects," says Krauzlis.

The superior colliculus is currently under renewed scrutiny because recent findings have suggested that it does more than help orient the head and eyes toward something seen or heard. Results hinted that the superior colliculus might play a role in analyzing the current environment and deciding whether one specific aspect is worth paying closer attention to than another. Definitive proof, however, has been lacking......... Posted by: Rose      Read more         Source

September 14, 2008, 10:42 PM CT

Extremely exact images from inside the body

It will be the only magnetic resonance tomograph of the modern 7 tesla generation in the world, in which a metrology institute is also involved. Magnetic resonance tomographs, which use a magnetic field of 7 tesla, have not yet been in operation in hospitals and clinics, but have solely served research. For the first time in the world, cardiovascular research carried out on such a device is now also to play an important role. The magnetic resonance tomograph costing approximately seven million Euros and weighing 35 tonnes was delivered to its new location, the Experimental and Clinical Research Center (ECRC) of the Max Delbrück Center (MDC) for Molecular Medicine in Berlin-Buch on 11th September.

In contrast to the 1.5 and 3 tesla devices which have largely been the norm to date, its higher magnetic field will provide sharper images and better insights into the smallest structures of the human body. The aim is to detect the risk or commencement of an illness at a very early stage in heart, brain and cancer research. Above all, heart research by magnetic resonance tomography is viewed as very difficult. As such, a demanding task will be waiting for PTB scientists from January 2009, when the device has been fully installed: as the partner dealing with physics and technical issues in the joint project, they are responsible for making the unique potential of this tomograph useful for applications in clinics. The PTB will, moreover, find the ideal conditions to advance its work on patient safety in high-field tomographs and on the development of new concepts in MRT imaging. The other partners in the project, besides the Max Delbrück Center and the PTB, are Siemens, the constructors of the 7 tesla device, and the Charite hospital. The new ultra-high-field MRT equipment of the ECRC has been completed with a 9.4 tesla small animal MRT of the Bruker company which was supplied three weeks ago......... Posted by: Jessica      Read more         Source

September 14, 2008, 10:04 PM CT

Newly found gene variants account for kidney diseases

For the first time, scientists have identified variations in a single gene that are strongly linked to kidney diseases disproportionately affecting African-Americans. This work was conducted by scientists at the National Institutes of Health (NIH) and by NIH-funded researchers at the Johns Hopkins University. The findings are published online today in two papers in Nature Genetics and would be reported in the October print issue.

"These two breakthrough genomic studies on kidney disease illustrate the importance of collaborations between researchers at NIH and NIH-funded researchers at Johns Hopkins," said NIH Director Elias A. Zerhouni, M.D. "This type of government-academic collaboration moves translational research forward and provides the knowledge base for developing new therapies for these chronic health disorders".

The scientists studied nondiabetic kidney diseases that can lead to chronic kidney disease and, in severe cases, to kidney failure requiring long-term dialysis or a kidney transplant. One of these diseases, focal segmental glomerulosclerosis (FSGS), is a kidney disease that leads to kidney failure in more than half of those with the disease over a period of about 10 years. Chronic kidney disease is caused by a number of different diseases and conditions and affects 26 million Americans. More than 106,000 individuals develop kidney failure and more than 485,000 receive dialysis or transplantation in the United States each year......... Posted by: Rose      Read more         Source

September 10, 2008, 8:53 PM CT

Cryopreservation techniques bring hopes for women

Emerging cryopreservation techniques are increasing hope of restoring fertility for women after diseases such as ovary cancer that lead to destruction of reproductive tissue. The same techniques can also be used to maintain stocks of farm animals, and protect against extinction of endangered animal species by maintaining banks of ovarian tissue or even nascent embryos that can used to produce offspring at some point in the future.

Until now these clearly related fields of research concerning preservation of animal and human ovarian tissue have been largely separate, but are now coming together to reinforce each other, following a highly successful workshop on cryopreservation of ovarian tissue, organised by the European Science Foundation (ESF). The human and animals cryopreservation fields have much to teach each other, and progress in both is likely to be accelerated as a result of growing collaboration, as per the ESF workshop's convenor Claus Yding Andersen.

Both parties can learn from each other," said Andersen. "Experiments which cannot be performed in women can be done in animal species," he noted, pointing out that much of the progress in humans has come as a result of animal experiments. But it is in humans where most successful transplantations of frozen ovarian tissue after thawing have been carried out, and where greatest experience in the field has been gained. Therefore the ESF conference considered how this could be applied to conservation of endangered species. "The vast experience in women, with several children born as a result of transplantation of frozen/thawed ovarian tissue, can be applied in endangered species to know where to implant and how to obtain pregnancies," said Andersen. The techniques will also be valuable in agriculture, for preserving ovaries of farm animals in tissue banks with the potential for subsequent re-creation......... Posted by: Rose      Read more         Source

April 17, 2008, 8:22 PM CT

Will screening for aortic aneurysm be effective?

Pilot screening programmes for abdominal aortic aneurysms in men aged 65 are due to be launched in England this year, but is this move too hasty? Two experts debate the issue in this weeks BMJ.

Around 90% of people with a ruptured aortic aneurysm die. But if the aneurysm is discovered before it ruptures and is repaired by an experienced vascular surgeon, mortality is around 7.4%, writes James Johnson, consultant surgeon at Halton General Hospital, Runcorn.

Around 5% of men aged between 65 and 74 have abdominal aortic aneurysms, but they rarely cause symptoms, so screening in this age group would potentially ensure that most aortic aneurysms are diagnosed and repaired.

But the case for screening is not clear-cut claims Johnson.

He points to wide variations in the mortality for surgical repair between hospitals in England. In addition, a number of patients will not be fit enough to have a repairaneurysm is a disease that rarely exists in isolation. Most patients will also have hypertension, or a history of myocardial infarction, stroke or diabetes.

As a result, a number of patients will be left with the knowledge that they have a life threatening condition that is liable to cause sudden death and that nothing can be done about it, writes Johnson......... Posted by: Rose      Read more         Source

April 17, 2008, 8:19 PM CT

Study finds 1 in 5 Iraq and Afghanistan veterans suffer from PTSD

Nearly 20 percent of military service members who have returned from Iraq and Afghanistan -- 300,000 in all -- report symptoms of post traumatic stress disorder or major depression, yet only slight more than half have sought therapy, as per a new RAND Corporation study.

In addition, scientists found about 19 percent of returning service members report that they experienced a possible traumatic brain injury while deployed, with 7 percent reporting both a probable brain injury and current PTSD or major depression.

A number of service members said they do not seek therapy for psychological illnesses because they fear it will harm their careers. But even among those who do seek help for PTSD or major depression, only about half receive therapy that scientists consider minimally adequate for their illnesses.

In the first analysis of its kind, scientists estimate that PTSD and depression among returning service members will cost the nation as much as $6.2 billion in the two years following deployment -- an amount that includes both direct medical care and costs for lost productivity and suicide. Investing in more high-quality therapy could save close to $2 billion within two years by substantially reducing those indirect costs, the 500-page study concludes......... Posted by: Rose      Read more         Source

April 17, 2008, 8:17 PM CT

Treatment To Prevent Allergic Reactions to Food

Scientists at National Jewish Medical and Research Center are conducting trials to evaluate a method to prevent allergic reactions to food. They are feeding peanut- and egg-allergic people increasing doses of an investigational protein extract from the foods to see if they can induce the participants' immune systems to tolerate the food.

"We hope these trials will lead to the development of the first active, preventive therapy for food allergies," said pediatric allergist David Fleischer, MD, principal investigator for the National Jewish studies. "If proved to be successful, it would offer great hope for allergic patients and their families, whose lives are haunted by a daily fear of food".

Currently the only advice doctors can give to the estimated 12 million Americans who have food allergies is to avoid the food and carry a self-injectable dose of epinephrine in case they accidentally consume the allergenic food. There is no therapy available to prevent an allergic reaction to food other than strict avoidance of that food. It can often be difficult to determine if a food contains peanuts or eggs, particularly when eating at a restaurant or food prepared by another person. It can even be difficult recognizing egg and peanut proteins listed on food ingredient labels, particularly from products that are not manufactured in the U.S. As a result, thousands of people rush to emergency rooms every year suffering severe allergic reactions to food. As a number of as 200 people die from allergic reactions to food each year......... Posted by: Rose      Read more         Source

March 24, 2008, 8:24 PM CT

Artificial Enzymes That Also Undergo 'Evolution In A Test Tube'

Mankind triumphed in a recent 'competition' against nature when researchers succeeded in creating a new type of enzyme for a reaction for which no naturally occurring enzyme has evolved. This achievement opens the door to the development of a variety of potential applications in medicine and industry.

Enzymes are, without a doubt, a valuable model for understanding the intricate works of nature. These molecular machines - which without them, life would not exist - are responsible for initiating chemical reactions within the body. Millions of years of natural selection have fine-tuned the activity of such enzymes, allowing chemical reactions to take place millions of times faster. In order to create artificial enzymes, a comprehensive understanding of the structure of natural enzymes, their mode of action, as well as advanced protein engineering techniques is needed. A team of researchers from the University of Washington, Seattle, and the Weizmann Institute of Science, Israel, made a crucial breakthrough toward this endeavor. Their findings have recently been reported in the scientific journal Nature.

Enzymes are biological catalysts that are made from a string of amino acids, which fold into specific three-dimensional protein structures. The scientists' aim was to create an enzyme for a specific chemical reaction whereby a proton (a positively charged hydrogen atom) is removed from carbon - a highly demanding reaction and rate-determining step in numerous processes for which no enzymes currently exist, but which would be beneficial in helping to speed up the reaction. During the first heat of the 'competition,' the research team designed the 'heart' of the enzymatic machine - the active site - where the chemical reactions take place......... Posted by: Rose      Read more         Source

March 24, 2008, 8:21 PM CT

Risky teen behavior may not occur at home or school?

How can scientists track where teens go when not in or near home or school to see if this movement has an impact on health-related behavior such as smoking or sexual activity" The answer is through that ubiquitous teen accessory the cell phone.

In a paper reported in the recent issue of the Journal of Adolescent Health scientists from Indiana University School of Medicine report on a pilot study which reviewed the feasibility of using global position system -enabled cell phones to track where 14- to 16-year-old girls spent their time.

We didnt know if the technology would work, if the kids would take the cell phones with them or would leave them at home. But they did carry the phones and the GPS data revealed that they were spending more time away from home, school and surrounding areas than anticipated. Learning that we were able to track their movement is important because prior studies which have looked at the effect of environment on teens have focused only on home, school and surrounding areas, said Sarah Wiehe, M.D., M.P.H., an assistant professor of pediatrics at the IU School of Medicine and a Regenstrief Institute affiliated scientist.

A persons environment in some way influences or is at least linked to their health and health outcomes and in the case of adolescents their health behaviors. But we dont have a great idea of why that association exists. What in the environment is contributing to behavior choices such as drug use" When tracked with GPS we know where the teens are and when they are there but we dont know what they are doing. Now that we know that the technology works, that the girls took their phones with them, we need to learn the characteristics of the environments in which they find themselves, she added......... Posted by: Rose      Read more         Source

March 24, 2008, 8:19 PM CT

Staph aureus resists our natural defenses

Scientists at the University of Washington have uncovered how the bacterium Staphylococcus aureus, including the notorious MRSA (methicillin-resistant Staph aureus) superbug strains, resists our body's natural defenses against infection. The work, which was featured on the cover of the March 21 issue of Science, could lead to new ways to fight the bacteria.

Dr. Ferric Fang, UW professor of laboratory medicine and microbiology, and his UW colleagues Dr. Anthony Richardson and Dr. Stephen Libby set out to determine what makes Staph aureus a better pathogen than other bacteria. They focused on a chemical compound called nitric oxide (NO), a natural antibiotic that our cells excrete to protect us from pathogens. For most bacteria, NO creates an environment that keeps invading microbes from undergoing respiration or fermentation, vital chemical processes that allow bacteria to grow.

The scientists observed that Staph aureus has a mechanism that allows it to produce lactic acid in the presence of NO, which allows it to maintain its chemical balance and keep growing and thriving in the harsh host environment. When Staph aureus is exposed to NO, it produces the novel enzyme responsible for lactic acid production, along with another enzyme that converts NO to non-toxic products. NO is usually found in the nose and nasal passages, and is meant to protect people against disease-causing microbes. But Staph aureus is usually found in the nose despite the presence of NO, the scientists explained......... Posted by: Rose      Read more         Source

March 7, 2008, 5:37 AM CT

Engineered protein shows potential as a strep vaccine

A University of California, San Diego-led research team has demonstrated that immunization with a stabilized version of a protein found on Streptococcus bacteria can provide protection against Strep infections, which afflict more than 600 million people each year and kill 400,000.

In the March 7 issue of the journal Science, the scientists describe, for the first time, the detailed structure of the streptococcal M protein, which is critical to the virulence of Group A Streptococcus (GAS). GAS causes a wide variety of human diseases including strep throat, rheumatic fever, and the life-threatening flesh-eating syndrome called necrotizing fasciitis. Studies were performed using M1 protein, which represents the version of M protein present on the most common disease-associated GAS strains.

The team also produced a variant of M1 protein that stimulates the immune system in mice, without the serious side effects caused by natural M1 protein. They say that their results should help researchers develop M1 protein-based vaccines against GAS.

Using X-ray crystallography, we determined that M1 protein has an irregular, unstable structure, explained Partho Ghosh, a professor of chemistry and biochemistry in UCSDs Division of Physical Sciences. We created a modified version of M1 with a more stable structure, and observed that it is just as effective at eliciting an immune reaction, but safer than the original version of M1, which has serious drawbacks to its use in a vaccine......... Posted by: Rose      Read more         Source

March 3, 2008, 9:51 PM CT

Gender differences in language appear biological

Eventhough scientists have long agreed that girls have superior language abilities than boys, until now no one has clearly provided a biological basis that may account for their differences.

For the first time -- and in unambiguous findings -- scientists from Northwestern University and the University of Haifa show both that areas of the brain linked to language work harder in girls than in boys during language tasks, and that boys and girls rely on different parts of the brain when performing these tasks.

Our findings which suggest that language processing is more sensory in boys and more abstract in girls -- could have major implications for teaching children and even provide support for advocates of single sex classrooms, said Douglas D. Burman, research associate in Northwesterns Roxelyn and Richard Pepper Department of Communication Sciences and Disorders.

Burman is primary author of Sex Differences in Neural Processing of Language Among Children. Co-authored by James R. Booth (Northwestern University) and Tali Bitan (University of Haifa), the article would be reported in the recent issue of the journal Neuropsychologia and now is available online at http://dx.doi.org/10.1016/j.neuropsychologia.2007.12.021.

Using functional magnetic resonance imaging (fMRI), the scientists measured brain activity in 31 boys and in 31 girls aged 9 to 15 as they performed spelling and writing language tasks......... Posted by: Rose      Read more         Source

January 14, 2008, 5:25 PM CT

Genetic determinants of Alzheimer's disease

The Netherlands, January 14, 2008 A rapid and accurate DHPLC assay for determination of apolipoprotein E genotypes has been developed by scientists from the Department of Medical Genetics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China. This assay combines PCR and DHPLC and can be used to conduct efficient genotyping of the human population, which in turn will help in the diagnosis and therapy of Alzheimers disease. A description of the assay has been published this month in the Journal of Alzheimers Disease.

Apolipoprotein E is a predisposing gene of Alzheimers disease and a number of other diseases. APOE has three major alleles, 2, 3 and 4. The combinations of the three common alleles result in six genotypes (22, 33, 44, 23, 34, and 24) that exist within the population. A number of studies indicate that people who have the E4 allele are at greater risk to develop Alzheimer's disease than those with the E3 allele and that the E2 allele may even help resist Alzheimer's disease. As a result, the rapid and accurate determination of APOE genotypes and the assessment of disease predisposition will be extremely valuable in augmenting the clinical diagnosis and therapy of the disease.

The medical genetic team, led by Professor Xiang-Min Xu at Southern Medical University, developed the assay during research funded by the National Science Fund for Distinguished Young Scholars of China. The polymerase chain reaction (PCR) was designed to generate the 191-bp amplicons containing two common polymorphisms within codons 112 and 158 in exon4 of the APOE gene. The PCR amplicons for each sample were subjected to denaturing high-performance liquid chromatography (DHPLC) analysis, which waccording toformed under partially denaturing conditions as determined by profiling the mixture of a tested sample and a homozygous standard control amplicon at the given ratio. In almost 300 samples detected, the accuracy of the assay reached 100%......... Posted by: Rose      Read more         Source