January 20, 2009, 7:02 PM CT

Older adults with anxiety disorders

Preliminary research suggests that use of the drug escitalopram provided some improvement in symptoms for elderly adults with generalized anxiety disorder, eventhough the overall benefits were diminished because of nonadherence to the drug by some patients, as per a research studyin the January 21 issue of JAMA

Generalized anxiety disorder (GAD), one of the most common psychiatric disorders in elderly adults, is defined by chronic, difficult-to-control worry and anxiety, with related symptoms such as muscle tension, sleep disturbance and fatigue. The prevalence of GAD is as high as 7.3 percent among community-dwelling elderly adults and even higher among primary care patients. Because the number of elderly adults in the U.S. is growing and there is a lack of effective therapy, GAD in elderly adults will become an increasing human and economic burden, as per background information in the article. Selective serotonin reuptake inhibitors (SSRIs) are effective for younger adults with GAD, but little data exist regarding the outcomes of their use by elderly adults.

Eric J. Lenze, M.D., of Washington University, St. Louis, and his colleagues examined the effectiveness, safety, and tolerability of the SSRI escitalopram for the therapy of GAD in elderly adults. The study included 177 participants age 60 years or older with a diagnosis of GAD, who were randomized to receive either 10 to 20 mg/d of escitalopram (n = 85) or matching placebo (n = 92) for 12 weeks. Anxiety and other outcomes were measured using many assessment tools......... Posted by: Emily      Read more         Source

January 20, 2009, 7:00 PM CT

Nutritional supplementation for children in Africa

Children in Niger who received a daily nutritional supplement for three months had a lower rate of weight loss and a reduced risk of wasting in comparison to children who did not receive the supplementation, as per a research studyin the January 21 issue of JAMA

Typically wasting (defined as a certain deviation that a child's weight is from the median [midpoint] weight of a child of the same height in a reference group) is characterized by the loss of weight and muscle mass. It affects approximately 10 percent of the world's children younger than 5 years and is an important factor in the risk of disease and death among this population. Ready-to-use-therapeutic foods (RUTFs) have been shown effective in the therapy of severe and moderate wasting, as per background information in the article. These foods are energy-dense, micronutrient-enriched pastes often made up of peanuts, oil, sugar and milk powder. The effectiveness of RUTFs in preventing moderate and severe wasting in children has not been previously reviewed.

Sheila Isanaka, B.A., of the Harvard School of Public Health, Boston, and his colleagues assessed the effect of a 3-month distribution of RUTF to nonmalnourished children in a region with traditionally high levels of child malnutrition and reviewed the effectiveness of a distribution of RUTF delivered at the village rather than the individual level. "The primary hypotheses were that village-level supplementation with RUTF in the months preceding the annual harvest would prevent declines in individual weight-for-height and reduce the occurence rate of wasting in children aged 6 to 60 months over a period of 8 months," the scientists write......... Posted by: Emily      Read more         Source

January 19, 2009, 6:11 AM CT

New step in DNA damage response

Scientists have identified a biochemical switch mandatory for nerve cells to respond to DNA damage.

The finding, scheduled for advance online publication in Nature Cell Biology, illuminates a correlation between proteins involved in neurodegenerative disease and in cells' response to DNA damage.

Most children with the inherited disease ataxia telangiectasia are wheelchair-bound by age 10 because of neurological problems. Patients also have weakened immune systems and more frequent leukemias, and are more sensitive to radiation.

The underlying problem comes from mutations in the ATM (ataxia telangiectasia mutated) gene, which encodes an enzyme that controls cells' response to and repair of DNA damage.

ATM can be turned on experimentally by treating cells with chemicals that damage DNA. After other proteins in the cell detected broken DNA needing repair, researchers had thought that the ATM protein could activate itself directly. Emory scientists have shown that an additional step is necessary first.

"In neurons that are not dividing anymore, we now know that another regulator is involved: Cdk5," says Zixu Mao, MD, PhD, associate professor of pharmacology and neurology at Emory University School of Medicine.

Working with postdoctoral fellows Bo Tian, PhD and Qian Yang, PhD, Mao observed that the Cdk5 protein must activate ATM before ATM can do its job in neurons......... Posted by: Emily      Read more         Source

January 15, 2009, 7:29 PM CT

Depressed adolescents not harmed

In a national clinical trial, adolescents with moderate to severe depression first given a placebo therapy and then an antidepressant medicine alone or in combination with treatment responded just as well over the long term as participants who received active therapy throughout the study, UT Southwestern Medical Center scientists report.

Scientists observed that at the end of nine months, children and teenagers first given placebo therapy for 12 weeks and then given active therapy had a response rate of 82 percent, in comparison to an 83 percent response rate for participants who received active therapy for the entire period.

The study, available Jan. 15 in the online advance edition of The American Journal of Psychiatry, is the first to address whether delaying effective therapy for adolescents assigned to initial therapy with a placebo group is ethical in research, said Dr. Betsy Kennard, associate professor of psychiatry at UT Southwestern and main author of the study.

"We don't want to put children and teenagers in any therapy that's harmful, and this shows that these adolescents were well cared for and went on to do just as well as the teens who initially received active therapys," Dr. Kennard said. "Without placebo groups, it's difficult to determine the efficacy of a therapy. Now we've shown scientifically that these trials are safe and effective. We do well by these kids"......... Posted by: Emily      Read more         Source

January 8, 2009, 9:59 PM CT

A good night's sleep protects against parasites

Animal species that sleep for longer do not suffer as much from parasite infestation and have a greater concentration of immune cells in their blood as per a research studyreported in the open-access journal BMC Evolutionary Biology

The question of why we sleep has long puzzled scientists. Brian Preston from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Gera number of, led an international team of scientists who tested the theory that sleep improves immune function. He says, "Sleep is a biological enigma. Despite occupying much of an animal's life, and having been scrutinized by numerous experimental studies, there is still no consensus on its function. Similarly, nobody has yet explained why species have evolved such marked variation in their sleep requirements (from 3 to 20 hours a day in mammals). Our research provides new evidence that sleep plays an important role in protecting animals from parasitic infection".

By comparing reported information about mammalian sleep, immune system parameters, and parasitism the authors show that evolutionary increases in mammalian sleep durations are strongly linked to the number of circulating immune cells. Mammalian species that sleep for longer periods also have substantially reduced levels of parasitic infection. As per Preston, "We suggest that sleep fuels the immune system. While awake, animals must be ready to meet multiple demands on a limited energy supply, including the need to search for food, acquire mates, and provide parental care. When asleep, animals largely avoid these costly activities, and can thus allocate resources to the body's natural defenses"......... Posted by: Emily      Read more         Source

January 8, 2009, 9:57 PM CT

Structure mediating spread of antibiotic resistance

Researchers have identified the structure of a key component of the bacteria behind such diseases as whooping cough, peptic stomach ulcers and Legionnaires' disease. The research, funded by the Wellcome Trust and the Biotechnology and Biological Sciences Research Council (BBSRC), sheds light on how antibiotic resistance genes spread from one bacterium to another. The research may help researchers develop novel therapys for these diseases and novel ways to curtail the spread of antibiotic resistance.

Antibiotic resistance spreads when genetic material is exchanged between two bacteria, one of which has mutated to be resistant to the drugs. This exchange is facilitated by a multi-component device known as a type IV secretion system, which acts to transport antibiotic resistance genes from within one cell, through its membrane and into a neighbouring cell.

Type IV secretion systems also play an essential role in transporting toxins or proteins from within bacteria into the cells of the body, causing diseases. Examples of Gram-negative bacterial pathogens using such a device are Helicobacter pylori (which causes peptic ulcers), Legionella pneumophila (which causes Legionnaires' disease), and Bordetella pertussis (which causes whooping cough).

Now, in a paper reported in the journal Science, researchers from the Institute of Structural and Molecular Biology (ISMB) at Birkbeck, University of London, and UCL (University College London) describe the structure of the core complex of a type IV secretion system, viewed using cryoelectron microscopy (a form of electron microscopy where the sample is studied at very low temperatures)......... Posted by: Emily      Read more         Source

January 6, 2009, 9:11 PM CT

Protein has pivotal role in obesity

A protein known to play a role in development and the formation of organs is also an important factor in the control of obesity and diabetes, said scientists from Baylor College of Medicine in a report that appears in the current issue of the journal Cell Metabolism

Drs. Ming-Jer and Sophia Tsai, professors of molecular and cellular biology at BCM, have studied COUP-TFII (Chicken Ovalbumin Upstream Promoter Transcription Factor II) for decades, but only when they bred mice that had only one gene copy for the factor did they find that the animals had smaller fat cells and increased energy metabolism as well as enhanced response to insulin.

"If a mouse loses one copy of the gene, the animal becomes lean," said Ming-Jer Tsai. "It is more sensitive to the effects of insulin and resistant to obesity from a high fat diet".

Their studies raise the likely possibility that one can use COUP-TFII as a potential drug target for diabetes and obesity therapy.

Identifying a drug that could reduce the effect of COUP-TFII activity has become a future focus for their research, said Sophia Tsai.

"We don't need to inhibit it totally," she said. "Partial inhibition will do the trick as when you lose one copy of the gene, your fat cells are already much smaller and the animal is lean"......... Posted by: Emily      Read more         Source

January 6, 2009, 7:42 PM CT

Evolution of Epilepsy

Two children have a seizure. One child never has another seizure. Twenty years later, the other child has a series of seizures and is diagnosed with epilepsy. A study being led by scientists at Rensselaer Polytechnic Institute is looking at what could possibly happen in the development of these two children that would lead to such extreme variations in their neurologic health.

The findings reveal that genetic predisposition, coupled with the occurrence of a patient's first seizures, could set the neurologic stage for the later onset of epilepsy. The scientists are now on the hunt to determine what blip in the genetic code could separate a child who will develop epilepsy from a child who will not.

The team's latest research, which is being reported in the January edition of Experimental Neurology, is led by Russell Ferland, an assistant professor of biology at Rensselaer within the Center for Biotechnology and Interdisciplinary Studies, and his graduate student Dominick Papandrea, in collaboration with Bruce Herron of the University at Albany and the Wadsworth Center.

To help understand seizure behavior in humans, the scientists first looked to understand the behavior in animal models. In particular, they analyzed specific strains of mice that exhibit striking seizure predispositions, which could offer a glimpse into why epilepsy only develops in certain patients following initial seizures......... Posted by: Emily      Read more         Source

January 6, 2009, 7:40 PM CT

Strong cheese?

An international research team led by Newcastle University has identified a new line of bacteria they believe add flavour to some of the world's most exclusive cheeses.

It's an age-old tradition that dates back at least 8,000 years but it seems we still have much to learn about the bacteria responsible for turning milk into cheese.

The team used DNA fingerprinting techniques to identify eight previously undiscovered microbes on the French cheese Reblochon.

One of France's great mountain cheeses, Reblochon is a 'smear-ripened' cheese where the surface of the cheese is washed with a salt solution containing bacteria. This process helps to spread the bacteria across the surface of the cheese, ripening it from the outside in.

Other popular smear-ripened cheeses on the Christmas cheeseboard include Port de Salut, Livarot, Taleggio, Limburger and the Irish cheese Gubbeen.

The team have named the microbes Mycetocola reblochoni after the cheese they were first discovered in.

Project lead Professor Michael Goodfellow of Newcastle University said: "It has always been thought the bacteria cheese makers were putting in at the start of the process gave Reblochon its distinctive flavour.

"What our research actually showed was this new group of bacteria - the reblochoni -were responsible for the ripening process, influencing the taste, texture and smell of the cheese"......... Posted by: Emily      Read more         Source

January 6, 2009, 7:34 PM CT

New method for bacterial toxin transfer

Researchers have discovered a new way for bacteria to transfer toxic genes to unrelated bacterial species, a finding that raises the unsettling possibility that bacterial swapping of toxins and other disease-aiding factors appears to be more common than previously imagined.

In a laboratory experiment, the researchers from NYU School of Medicine discovered that Staphylococcus aureus, a notorious bacterium that causes toxic shock syndrome and a number of other types of infections and is the scourge of hospitals nationwide due to its growing antibiotic resistance, could co-opt viral parasites as secret pipelines for transferring toxin genes to vastly different bacterial species.

Microbes have been known to gain antibiotic resistance through the transfer of plasmids, extra-chromosomal pieces of DNA that can be shuttled between unrelated bacteria. Some Staph aureus strains, in particular, have become major public health concerns after gaining antibiotic resistance through plasmids transferred from other species.

The startling new finding, reported in the Jan. 2, 2009, issue of Science by John Chen, Ph.D., and Richard Novick, M.D., suggests that Staph aureus also can take advantage of bacteriophages, viruses that infect bacteria, to pass genetic material on to completely unrelated bacteria. In the lab, the scientists showed that Staph could transfer genes for deadly toxic shock to Listeria monocytogenes, which is already known to cause a potentially deadly form of food poisoning. This is the first time that phages have been observed to serve as shuttle vehicles for bacterial toxins between different species......... Posted by: Emily      Read more         Source