Gene fusion is the ‘smoking gun’ in the development of prostate cancer: Study

May 19, 2010 By Leave a Comment

Washington, May 19 (ANI): Targeting the hormone androgen and its receptor in prostate cancer therapy could be a wrong approach after all, says a new study.

Researchers have found that when two genes fuse together to cause prostate cancer, it blocks the receptor for the hormone androgen, preventing prostate cells from developing normally.

The study, from the University of Michigan Comprehensive Cancer Center, has indicated that the gene fusion – not the androgen receptor – is a more specific “bad actor” in prostate cancer and is the real smoking gun that should be targeted by treatments.

“We need to begin to think about targeting prostate cancer by targeting the gene fusion, and not confining our approaches to androgen receptor. If we’re going to find a more durable therapy, we need to get at the gene fusion,” said study author Dr. Arul Chinnaiyan.

Treatments for prostate cancer typically include drugs to moderate androgen, a male hormone that controls the normal growth of the prostate.

These drugs typically work at first, but over time the cancer cells become resistant to the therapy and the cancer returns.

As it is no longer responsive to currently available hormone deprivation therapies, the recurrent cancer is usually more difficult to treat.

In 2005, the researchers identified a prostate-specific gene called TMPRSS2 that fuses with a cancer-causing gene called ERG.

The team’s earlier research has shown that this gene fusion acts as an “on switch” to trigger prostate cancer.

The new study used sophisticated sequencing technologies to map the genome-wide location of androgen receptor and the TMPRSS2-ERG gene fusion in prostate cancer cells.

The researchers found that the gene fusion blocks the androgen receptor directly and also interferes with it at the genetic level to prevent normal androgen receptor signalling.

With the androgen receptor blocked, prostate cells stop growing and developing normally, allowing cancer to develop.

“Our study shows the underlying problem in prostate cancer is the presence of a gene fusion, not the androgen receptor. In many contexts, androgen signaling is actually a good thing, but the presence of the gene fusion blocks androgen receptor signaling, which alters normal prostate cell development. While current treatments for advanced prostate cancer are focused on hormone deprivation and are quite effective, at least initially, future therapies need to be developed that target the prostate cancer gene fusion,” said Chinnaiyan.

The study is featured on the cover of the latest issue of Cancer Cell. (ANI)

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Behavioural therapy may help reduce tics in kids with Tourette syndrome

May 19, 2010 By Leave a Comment

Washington, May 19 (ANI): A new study led by a UCLA researcher has developed an effective, non-medication treatment for children and adolescents with Tourette”s and related tic disorders that has shown improvement similar to that found in recent anti-tic medication studies.

Tourette syndrome, a neurological disorder characterized by twitches like grimacing, blinking and vocalizations, is normally treated in children and teens with one of several antipsychotic medications.

But such drugs usually don”t cure tics completely, and worse, they can often have side effects, acting as sedatives, causing weight gain and impairing cognitive function.

Now, lead study author John Piacentini, a UCLA professor of psychiatry and his colleagues at seven sites around the nation found that a specialized form of behavior therapy called comprehensive behavioural intervention for tics, or CBIT, significantly reduced chronic tics and tic-related problems in children and adolescents.

Almost 53 percent of children receiving CBIT were rated as significantly improved, compared with 19 percent of those receiving a comparison treatment.

Tourette’s syndrome is often accompanied by other psychiatric problems, difficulties in school, work and social functioning.

In this new kind of therapy, children learned to recognize when a tic was about to occur and to engage in a voluntary action incompatible with the tic until the unwanted sensation passed.

Parents were also taught how to aid there children in such situations and reduce stressful conditions for their kids.

“The fact that CBIT works about as well as the standard medications for tics but without the negative side effects greatly expands the available treatment options for chronic tic disorders,” said Susanna Chang, a UCLA assistant professor of psychiatry and a study author. “Importantly, CBIT also emphasizes the development of skills that foster autonomy and empowerment, allowing for patients and their families to take a more active role in treatment than previously indicated.”

Piacentini are considering using neuroimaging and other neuroscientific techniques to examine the brain mechanisms underlying how CBIT might work.

In addition, investigators are currently working with the Tourette Syndrome Association and the U.S. Centers for Disease Control and Prevention to teach CBIT to clinicians who treat children with tic disorders and to develop new versions of CBIT for use with younger children and by nurses and other health care professionals.

The study appears in the May 19 issue of the Journal of the American Medical Association (JAMA). (ANI)

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Viagra may cause hearing loss

May 19, 2010 By Leave a Comment

Washington, May 19 (ANI): Researchers have found a link between hearing loss and the use of the erectile dysfunction drug Viagra.

Gerald McGwin, a professor of epidemiology at the School of Public Health in the University of Alabama at Birmingham claims use of Viagra can result in long-term hearing loss. Also, use of other phosphodiesterase type 5 inhibitors (PDE-5i) drugs such as Cialis and Levitra can be harmful for the ear, but results on those drugs are inconclusive.

Study author Gerald McGwin, a professor of epidemiology in the UAB School of Public Health, said: “It appears from these findings that the current government warning regarding hearing loss and the use of PDE-5i medications is warranted.

“Though there are limitations to this study, it is prudent that patients using these medications be warned about the signs and symptoms of hearing impairment and be encouraged to seek immediate medical attention to potentially forestall permanent damage.”

In 2007, following the report of several case studies potentially linking PDE-5i use and sudden hearing loss, the Food and Drug Administration announced labeling changes for PDE-5i medications so that the risk of hearing problems was more prominently displayed. McGwin said this is the first epidemiologic study to evaluate the relationship between PDE-5i drugs and long-term hearing loss.

McGwin examined data on 11,525 men over 40 years of age gathered by the Medical Expenditure Panel Survey, a survey conducted by the federal Agency for Healthcare Research and Quality between 2003 and 2006. Men who reported use of PDE-5i medications were twice as likely to also report hearing loss as were men who had not used the drugs.

McGwin said the relationship was strongest for men reporting use of sildenafil (Viagra) over those who used tadalafil (Cialis) or vardenafil (Levitra), a finding he attributed in part to a small sample size for both of the latter drugs. McGwin said the findings indicated an elevated but not statistically significant increase in hearing loss for users of tadalafil and vardenafil.

PDE-5i drugs were originally designed to treat pulmonary hypertension and are now used extensively in the treatment of erectile dysfunction (ED). McGwin said one important consideration in evaluating the nature of the relationship between the drugs and hearing is the existence of a plausible biological mechanism of how these drugs might cause hearing loss.

McGwin said: “PDE-5i medications work in ED patients by their ability to increase blood flow to certain tissues in the body. It has been hypothesized that they may have a similar effect on similar tissues in the ear, where an increase of blood flow could potentially cause damage leading to hearing loss.”

McGwin acknowledged limitations in the study, including the limited sample size for tadalafil and vardenafil, concerns over under-reporting of use of PDE-5i medications and confounding factors such as pre-existing conditions that might also contribute to hearing loss. He suggested that additional research regarding the risk from PDE-5i is necessary due to the largely irreversible nature of hearing loss and its impact on quality of life.

McGwin concluded: “The results of the current study in conjunction with a plausible biologic mechanism lend support to the FDA”s decision to warn patients about the potential risk posed by PDE-5i use”.

The study has been published in Archives of Otolaryngology-Head and Neck Surgery. (ANI)

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Viagra may cause hearing loss

May 19, 2010 By Leave a Comment

Washington, May 19 (ANI): Researchers have found a link between hearing loss and the use of the erectile dysfunction drug Viagra.

Gerald McGwin, a professor of epidemiology at the School of Public Health in the University of Alabama at Birmingham claims use of Viagra can result in long-term hearing loss. Also, use of other phosphodiesterase type 5 inhibitors (PDE-5i) drugs such as Cialis and Levitra can be harmful for the ear, but results on those drugs are inconclusive.

Study author Gerald McGwin, a professor of epidemiology in the UAB School of Public Health, said: “It appears from these findings that the current government warning regarding hearing loss and the use of PDE-5i medications is warranted.

“Though there are limitations to this study, it is prudent that patients using these medications be warned about the signs and symptoms of hearing impairment and be encouraged to seek immediate medical attention to potentially forestall permanent damage.”

In 2007, following the report of several case studies potentially linking PDE-5i use and sudden hearing loss, the Food and Drug Administration announced labeling changes for PDE-5i medications so that the risk of hearing problems was more prominently displayed. McGwin said this is the first epidemiologic study to evaluate the relationship between PDE-5i drugs and long-term hearing loss.

McGwin examined data on 11,525 men over 40 years of age gathered by the Medical Expenditure Panel Survey, a survey conducted by the federal Agency for Healthcare Research and Quality between 2003 and 2006. Men who reported use of PDE-5i medications were twice as likely to also report hearing loss as were men who had not used the drugs.

McGwin said the relationship was strongest for men reporting use of sildenafil (Viagra) over those who used tadalafil (Cialis) or vardenafil (Levitra), a finding he attributed in part to a small sample size for both of the latter drugs. McGwin said the findings indicated an elevated but not statistically significant increase in hearing loss for users of tadalafil and vardenafil.

PDE-5i drugs were originally designed to treat pulmonary hypertension and are now used extensively in the treatment of erectile dysfunction (ED). McGwin said one important consideration in evaluating the nature of the relationship between the drugs and hearing is the existence of a plausible biological mechanism of how these drugs might cause hearing loss.

McGwin said: “PDE-5i medications work in ED patients by their ability to increase blood flow to certain tissues in the body. It has been hypothesized that they may have a similar effect on similar tissues in the ear, where an increase of blood flow could potentially cause damage leading to hearing loss.”

McGwin acknowledged limitations in the study, including the limited sample size for tadalafil and vardenafil, concerns over under-reporting of use of PDE-5i medications and confounding factors such as pre-existing conditions that might also contribute to hearing loss. He suggested that additional research regarding the risk from PDE-5i is necessary due to the largely irreversible nature of hearing loss and its impact on quality of life.

McGwin concluded: “The results of the current study in conjunction with a plausible biologic mechanism lend support to the FDA”s decision to warn patients about the potential risk posed by PDE-5i use”.

The study has been published in Archives of Otolaryngology-Head and Neck Surgery. (ANI)

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Old age falling tied to altered blood flow in brain

May 18, 2010 By Leave a Comment

Washington, May 18 (ANI): Altered blood flow in the brain due to high blood pressure and other conditions may lead to falls in elderly people, a new study has shown.

The research has been published in the May 18, 2010, issue of Neurology.

“At age 60, 85 percent of people have a normal walking ability. However, by age 85, only 18 percent of seniors can walk normally,” said study author Farzaneh A. Sorond, MD, PhD, with Brigham and Women’s Hospital, Hebrew SeniorLife’s Institute for Aging Research and Harvard Medical School in Boston and a member of the American Academy of Neurology.

For the study, researchers followed 419 people age 65 or older. Ultrasound tests were used to measure brain blood flow response to carbon dioxide levels, a standard test of blood vessel function in the brain. Walking speed was measured by a four-meter walking test. The seniors and their caregivers reported any falls that occurred over two years.

The study found that the 20 percent of people who had the smallest blood flow changes in the brain were at a 70 percent higher risk of falling compared to the 20 percent of people who had the largest blood flow changes in the brain. Those with the slowest rate had an average of nearly 1.5 falls per year, compared to less than one fall per year for those with the highest rate.

“Our findings suggest there could be a new strategy for preventing falls, such as daily exercise and treatments for high blood pressure, since blood pressure affects blood flow in the brain and may cause falls,” said Sorond. (ANI)

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Epileptic kids say quality of life better than their parents think

May 14, 2010 By Leave a Comment

Washington, May 14 (ANI): Children with epilepsy say their quality of life is comparable to that of their healthy siblings, researchers have reported.

Epileptic kids often face multiple challenges — not only seizures but learning, cognitive and school difficulties, side effects from medication, and social stigma from their peers.

It”s no wonder parents say their children with epilepsy have a substantially worse quality of life than their other, healthy children.

However, a new study, reported in the current online edition of the journal Value in Health, by study author Dr. Christine Bower Baca, a Robert Wood Johnson Clinical Scholar and a clinical instructor in the UCLA Department of Neurology, and her colleagues, paints a different picture all together.

Epilepsy is a common chronic neurological condition that can negatively impact physical, social and psychological function.

There are many causes of epilepsy in children, including problems with brain development before birth, lack of oxygen during or following birth, head injuries, tumors, prolonged seizures with fevers, genetics, or infections in the brain.

In the study, researchers assessed 143 children with epilepsy, matching each to a healthy, non-epileptic sibling as a control, and to their parents or guardians. The assessment was done by conducting personal interviews eight to nine years after a child”s initial diagnosis, using the Child Health Questionnaire, a generic and well-established measure with both child and parent versions. The average age of the children with epilepsy when interviewed was 12.

The researchers found that parents” ratings of their children”s quality of life were significantly lower for their children with epilepsy on 10 of 12 scales measuring such things as behavior, general health, self-esteem and physical function. In contrast, children with epilepsy rated their own quality of life on a par with their siblings.

As for the difference, one possible explanation, Baca said, is known as the “disability paradox,” the idea that having a chronic disease or a disability does not necessarily mean that a person is unsatisfied with his or her life, despite what others may think.

“In this regard, parental perception of their epileptic child may be distorted because of their perception that they have a child that is ”sick,”” Baca said. “Such a distortion could lead to an underestimate of the child”s quality of life.”

Also, the concerns of a child with epilepsy may differ from those of a parent.

“Children and parents may draw on different values and perspectives to evaluate quality of life and may not be aware of these different perspectives,” Baca said. (ANI)

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Dietary protein may help prevent hip fractures

May 5, 2010 By Leave a Comment

Washington, May 5 (ANI): Higher levels of dietary protein may protect seniors from hip fractures, a new study claims.

The new study was conducted by the Institute for Aging Research of Hebrew SeniorLife in Boston, an affiliate of Harvard Medical School.

The study, which examined the daily protein intake of 946 seniors from the Framingham Osteoporosis Study, found that individuals who were in the lowest 25 percent of dietary protein intake had approximately 50 percent more hip fractures than those who consumed greater amounts of dietary protein (all within normal intakes). Those who suffered hip fractures consumed less than the 46 grams of dietary protein per day recommended for adults.

“Study participants who consumed higher amounts of protein in their diet were significantly less likely to suffer a hip fracture,” says senior study author Marian T. Hannan, D.Sc., M.P.H., co-director of the Musculoskeletal Research Program at the Institute for Aging Research.

The study will be published this week in the online-first edition of Osteoporosis International. (ANI)

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Broccoli may help fight breast cancer

May 4, 2010 By Leave a Comment

Washington, May 4 (ANI): A broccoli compound may help prevent or treat breast cancer by targeting cancer stem cells, according to a new study.

Stem cells are the small number of cells that fuel a tumor”s growth.

The study from researchers at the University of Michigan Comprehensive Cancer Center tested sulforaphane, a component of broccoli and broccoli sprouts, in both mice and cell cultures.

Researchers found sulforaphane targeted and killed the cancer stem cells and prevented new tumors from growing.

“Sulforaphane has been studied previously for its effects on cancer, but this study shows that its benefit is in inhibiting the breast cancer stem cells. This new insight suggests the potential of sulforaphane or broccoli extract to prevent or treat cancer by targeting the critical cancer stem cells,” says study author Duxin Sun, Ph.D., associate professor of pharmaceutical sciences at the U-M College of Pharmacy and a researcher with the U-M Comprehensive Cancer Center.

Results of the study appear in the May 1 issue of Clinical Cancer Research. (ANI)

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Source of ‘noise’ in HIV identified

April 21, 2010 By Leave a Comment

Washington, April 21 (ANI): Scientists in the U.S. have discovered a molecular mechanism that the human immunodeficiency virus (HIV) seems to utilize for generating random fluctuations called ‘noise’ in its gene expression.

The research has identified the likely source of HIV gene-expression noise and offers intriguing insight into the role of this noise in driving HIV”s fate decision between active replication and latency.

After infecting a human cell, HIV integrates into the genome and typically begins to actively replicate. However, the virus can also enter a long-lived latent state, which remains the greatest barrier to eradicating virus from the patient.

Senior study author, Dr. Leor S. Weinberger, a molecular virologist and systems biologist from the Department of Chemistry and Biochemistry at the University of California, San Diego, recently showed that noise in HIV gene-expression critically influences the viral decision to enter either active replication or latency. However, the source of the noise was not clear.

To probe the source of this inherent noise in HIV gene expression, Dr. Weinberger and colleagues exploited a technique from electrical engineering that analyzes how noise changes across different levels of expression.

The researchers examined cells carrying a single integrated copy of HIV engineered to produce a quantifiable protein, and measured HIV-1 expression noise at dozens of different viral integration sites which act as distinct genetic environments for viral gene expression.

The researchers found that HIV noise levels are substantially higher than measured in other organisms, and that HIV gene expression occurs in randomly timed bursts.

During these expression bursts, multiple copies of HIV gene products are produced that leads to the high noise levels in HIV gene expression.

The bursting model argues that during active expression HIV cycles between periods of silence and bursting and provides insight into how HIV may be activated by host signaling molecules.

“We know that noise in gene-expression can critically influence HIV”s entry to proviral latency. These new results point to transcriptional bursting as a major source of the noise,” Dr. Weinberger said

“This finding that transcriptional bursting generates an exceptionally noisy HIV promoter, noisier than almost all other measured promoters, supports the theory that latency may be fundamental to the HIV life cycle and that HIV evolved for probabilistic entry into latency,” Dr. Weinberger added.

The study has been published in the April 20th issue of the Biophysical Journal. (ANI)

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Gene variant could protect memory and thinking skills in older people

April 20, 2010 By Leave a Comment

Washington, Apr 20 (ANI): A gene variant could help protect the memory and thinking skills of older people, according to a new research.

For the study, researchers followed 2,858 African-American and Caucasian people between the ages of 70 and 79 for eight years.

Participants” DNA was analysed for the catechol-O-methyltransferase (COMT) gene, a gene shown in studies to affect thinking skills.

The allelic variants associated with this gene are the Val and Met variants.

“This is the first study to identify a protective relationship between this gene variant and cognitive function,” said study author Dr. Alexandra Fiocco, with the University of California, San Francisco.

The group was also given two types of thinking tests. One test measured skills such as language, concentration and memory.

The other test measured response time, attention and judging sights and objects.

The study found that the Met variant of the COMT gene was linked to a greater decline in thinking skills over the years, while the Val variant had a protective effect on thinking skills, with lower declines over the years.

In Caucasians, those with the Val variant scored 33 percent better over time than those without the variant. Among African-Americans, people with the Val allele gene variant scored 45 percent better over time than those who did not have the variant.

“This finding is interesting because in younger people, the Val genotype has been shown to have a detrimental effect. But in our study of older people, the reverse was true. Finding connections between this gene, its variants and cognitive function may help scientists find new treatments for the prevention of cognitive decline,” said Fiocco.

However, he added that the results need to be replicated by others before the field can be confident that the Met variant of the COMT gene plays a role in late life cognitive decline.

The research will be published in the latest issue of Neurology, the medical journal of the American Academy of Neurology. (ANI)

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12-week program can make binge eaters eat less

April 1, 2010 By Leave a Comment

Washington, Apr 1 (ANI): A self-guided, 12-week program could make binge eaters eat less for up to a year and even save money for those who participate, according to a new study.

Conducted by researchers at the Kaiser Permanente Center for Health Research, Wesleyan University and Rutgers University, the first-of-a-kind study found that more than 63 percent of participants had stopped binging at the end of the program – compared to just over 28 percent of those who did not participate.

The program lasted only 12 weeks, but most of the participants were still binge free a year later.

Another study found that program participants saved money because they spent less on things like dietary supplements and weight loss programs.

“It is unusual to find a program like this that works well, and also saves the patient money. It”s a win-win for everyone. This type of program is something that all health care systems should consider implementing,” said study author Dr. Frances Lynch.

“People who binge eat more than other people do during a short period of time and they lose control of their eating during these episodes. Binge eating is often accompanied by depression, shame, weight gain, loss of self-esteem and it costs the healthcare system millions of extra dollars. Our studies show that recurrent binge eating can be successfully treated with a brief, easily administered program, and that”s great news for patients and their providers,” said the study”s principal investigator Dr. Ruth H. Striegel-Moore.

The new diagnosis could focus more attention on binge eating and how best to treat it, according to the researchers.

It also could influence the number of people diagnosed and how insurers will cover treatment.

This randomized controlled trial, conducted in 2004-2005, involved 123 members of the Kaiser Permanente health plan in Oregon and southwest Washington.

By the end of the 12-week program 63.5 percent of participants had stopped binging, compared to 28.3 percent of those who did not participate.

Six months later, 74.5 percent of program participants abstained from binging, compared to 44.1 percent in usual care.

At one year, 64.2 percent of participants were binge free, compared to 44.6 percent of those in usual care.

They also found that participants in the intervention group spent less on weight loss programs and over-the-counter medications and supplements.

The study has been published in the April issue of the Journal of Consulting and Clinical Psychology. (ANI)

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Protein leads to problems with executive thinking skills

March 30, 2010 By Leave a Comment

Washington, Mar 30 (ANI): A high level of C-reactive protein (CRP), a marker for inflammation in the blood, leads to brain changes that are linked to problems with executive thinking skills, according to a new study.

For the study, scientists examined 447 stroke and dementia-free people with an average age of 63.

Participants underwent MRI brain scans such as diffusion tensor imaging (DTI), a technique that measures water molecule movements in the brain.

They also completed tests that measured verbal memory, word fluency and executive function, the process in the brain that allows for planning, decision making and selection of appropriate behaviour.

The study found that higher levels of CRP led to worse performance in executive function.

Higher levels of the protein also affected the frontal lobe of the brain, where some motor functions take place. Motor skills, however, were not measured in the study.

Other areas of cognition, such as memory and language skills, showed no association with CRP.

Overall, the average time to complete a test of executive function was 85 seconds.

Those with the highest levels of CRP took an average of seven seconds longer to complete the test than those with the lowest levels of the protein.

The brain changes measured with DTI were equivalent to 12 years of aging for those with the highest levels of CRP compared to those with the lowest levels.

“The use of aspirin and statin drugs as well as physical activity and controlling weight can help lower CRP levels in the body, but our analyses did not consider whether therapy would be effective or not,” said study author Dr. Heike Wersching, with the University of Munster in Germany.

The study is published in the latest issue of Neurology, the medical journal of the American Academy of Neurology. (ANI)

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Surgical masks as effective as respirators in preventing H1N1 spread

March 26, 2010 By Leave a Comment

Washington, March 26 (ANI): Surgical masks provide effective protection to health-care workers against H1N1, a new study has found.

Researchers analysed the incidence of H1N1 among health care workers from April through August of 2009 at Tan Tock Seng Hospital in Singapore.

A small percentage tested positive for H1N1 during this period. None had cared for any patients with H1N1 or worked in H1N1 screening areas of the emergency room.

In all cases, transmission was believed to have occurred outside of patient care, when health care workers were in contact with roommates, the general public, and other sources.

From June 19 to July 21, health care workers at the hospital wore N95 respirators in the emergency room and an H1N1 isolation area. From July 22 to Aug. 31, surgical masks were used by workers in these areas. The incidence of H1N1 among workers remained low during both periods.

While the study was observational, the findings suggest that surgical masks and respirators did not differ in their effectiveness in preventing hospital staff from acquiring H1N1.

Study author Brenda Sze Peng Ang, MD, of the Tan Tock Seng Hospital in Singapore said: “What is more important than using high-filtration or respirator masks for known or suspected cases is to have a uniform policy, such as using surgical masks, when in close contact with all patients.

“This way, health care workers are protected from getting infected by patients not initially thought to have H1N1.”

The study has appeared in the April 1, 2010 issue of Clinical Infectious Diseases. (ANI)

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HIV patients ‘at increased community acquired MRSA infection risk’

March 24, 2010 By Leave a Comment

Washington, March 24 (ANI): A new study has shown that HIV-infected patients are at a markedly increased risk for community acquired Methicillin-resistant Staphylococcus aureus (CA-MRSA) infections.

In the study, researchers at John H. Stroger, Jr. Hospital of Cook County and Rush University Medical Center found that the incidence of CA-MRSA in the Chicago area was six-fold higher among HIV-infected patients than it was among HIV-negative patients.

Using electronic data, the study authors retrospectively studied HIV-infected patients with CA-MRSA who received medical care during the period of 2000 to 2007 in the regional Cook County Health and Hospitals System. Researchers used patients” zip codes to examine where the cases were distributed geographically.

Overall incidence of CA-MRSA increased significantly for all populations in Cook County from the first period (2000- 2003) to the second period (2004-2007). The incidence increased four-fold from 61 cases to 253 cases per 100,000 HIV-negative patients and nearly four-fold from 411 cases to 1474 cases per 100,000 HIV-infected patients, respectively.

“HIV does not cause CA-MRSA, but our study shows an association between HIV and CA-MRSA. The next steps are to find out what is going on in the community to cause these infections,” said study author Dr. Kyle Popovich, an infectious disease specialist at Rush University Medical Center.

“We believe the risk may be amplified by overlapping community-based social networks of high-risk patients,” Popovich added.

The study has been published in the April 1 issue of the journal Clinical Infectious Diseases. (ANI)

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Cognitive decline 4 times faster in Alzheimer”s patients

March 23, 2010 By Leave a Comment

Washington, Mar 23 (ANI): Cognitive abilities decline four times faster in Alzheimer”s patients than those without any cognitive impairment, say researchers at Rush University Medical Center in Chicago.

The research is the second population-based study to quantify the rate of cognitive decline in Alzheimer”s disease.

“Knowledge about the progressive cognitive decline in Alzheimer”s disease is mainly based on studies of persons evaluated in clinical settings. In such studies, the full spectrum of the disease is unlikely to be represented. As a result, it has been difficult to securely determine the cognitive consequences of the disease and to test whether they vary in racial or ethnic subgroups of the population,” said study author Dr. Robert S. Wilson.

The researchers aimed to quantify the rates of cognitive decline in people who developed Alzheimer”s disease and its precursor, mild cognitive impairment.

The study followed 1,168 older adults. At the beginning of the study, participants did not have dementia.

After a mean of five to six years, they had a detailed clinical evaluation and 614 persons were found to have no cognitive impairment, 395 had mild cognitive impairment, and 149 had Alzheimer”s disease. They then completed brief cognitive testing at 3-year intervals for a mean of five and half years.

In comparison to the no cognitive impairment group, the annual rate of cognitive decline was increased more than twofold in those with mild cognitive impairment and more than fourfold in those with Alzheimer”s disease. The results did not vary by race, sex, or age.

“This study is especially significant because half of the participants are African Americans. Most of what we know about Alzheimer”s disease is based on studies of Caucasians. Our study found no difference in how the disease played out in the two races,” said Wilson.

The study is published in the latest issue of the journal Neurology, the medical journal of the American Academy of Neurology. (ANI)

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Why we tend to be nice with strangers

March 20, 2010 By Leave a Comment

Washington, Mar 20 (ANI): People from large industrialized societies tend to be nice with strangers. Now, researchers have found why we are surprisingly fair and trusting with unfamiliar individuals.

This pro-social behaviour results from a change in social norms that allowed us to trust strangers, according to the new study.

The change is likely linked to a rise in markets where goods are exchanged for money, as well as increased participation in major world religions.

The finding challenges a previously suggested theory— the idea that we treat strangers fairly because we mistakenly transferred our feelings of kinship to unrelated individuals as societies grew.

The results, based on more than 2,000 participants from 15 societies across the globe, show that “fair” behaviour during a bargaining game increases the more a society has incorporated market exchange and world religions.

“Measures of fairness toward anonymous others, in terms of motivations and beliefs, vary dramatically across human societies. And we can explain most of the variation between groups by the degree of market incorporation and the presence of a world religion,” Live Science quoted study author Joseph Henrich, an anthropologist at the University of British Columbia, Canada, as saying.

According to researchers, in order for market exchange to really take off, societies had to evolve new norms for interacting with strangers.

Similarly, major world religions, with their beliefs about fairness and punishment, could have also influenced changes norms and allowed societies to grow.

Religions in small-scale societies tend to lack such moralizing gods that are concerned with generosity toward strangers, said Henrich.

“One of the things that might have occurred through cultural evolution to help build these larger groups, is the evolution of religious systems with supernatural agents that were in some sense police, concerned about those elements of behavior that would facilitate exchange and trade and harmonious groups, allowing groups to get larger and larger,” he said.

To test out these ideas, the researchers studied participants from small-scale communities in Africa, North and South America, Oceania, New Guinea, and Asia.

The subjects played three bargaining games.

Very small communities with almost no market integration and less involvement in world religions generally made lower, or less fair, offers during the games, and were less willing to punish unfair offers.

On the flip side, the largest societies with the most market integration and world religion participation made higher offers, and were more willing to penalize those who made unfair offers.

“This is consistent with the idea that the expansion of human societies was driven by the evolution of these norms that allowed people to interact with strangers,” said Henrich.

The results will be published in the journal Science. (ANI)

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Even pre-human ancestors cried while cutting onions

March 20, 2010 By Leave a Comment

Washington, Mar 20 (ANI): The body sensors that bring tears in your eyes when you’re cutting onions have been around for 500 million years, says a new study.

According to a report by Brandeis University scientists in Nature, whenever a person chokes on acrid cigarette smoke or feels like he/she is burning up from a mouthful of wasabi-laced sushi, the response is triggered by a primordial chemical sensor conserved across some 500 million years of animal evolution.

Such substances contain tissue-damaging and irritating chemicals. When you get a taste or waft of them, a protein found throughout your body is thought to sense these irritating chemicals and send signals to your nervous system. The result is pain, which results in the tears, reports Live Science.

In the new study, chemical-sensing protein, called TRAPA1, was found in flies. And, according to the boffins, the protein could date back millions of years to the common ancestor of all the varied creatures in the animal kingdom.

“While many aspects of other chemical senses like taste and smell have been independently invented multiple times over the course of animal evolution, the chemical sense that detects these reactive compounds is different,” said study author Paul Garrity, a biologist at Brandeis University in Waltham, Mass. “It uses a detector we have inherited in largely unaltered form from an organism that lived a half-billion years ago, an organism that is not only our ancestor, but the ancestor of every vertebrate and invertebrate alive today.”

Using a variety of bioinformatic methods (bioinformactics applies computer programs and statistic techniques to study biological data), Garrity and his colleagues reconstructed TRPA1”s family tree back some 700 million years.

They then used several computer programs to figure out how the proteins would relate to each other in terms of evolution.

“We discovered that a new branch split off the tree at least 500 million years ago, and that this new branch, the TRPA1 branch, appeared to have had all the features needed for chemical sensing even back then,” Garrity said. “Since that time, it appears that most animals, including humans, have maintained this same ancient system for detecting reactive chemicals.” (ANI)

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As pot belly expands, sudden cardiac death risk shrinks

March 17, 2010 By Leave a Comment

Washington, Mar 17 (ANI): Being skinny confers no advantage when it comes to the risk of dying suddenly from cardiac causes, say researchers.

In fact, boffins at the University of Rochester Medical Center found that non-obese heart failure patients – including overweight, normal and underweight patients – had a 76 percent increase in risk of sudden cardiac death compared to obese heart failure patients. Normal and underweight patients showed a startling 99 percent increase in risk for sudden cardiac death compared to obese patients.

The results have been presented at the American College of Cardiology Annual Scientific Session in Atlanta.

The study, by researchers from one of the world’s leading groups on sudden cardiac death, is the first to assess the relation between BMI and the risk of sudden cardiac death.

“This study is important because it not only answers questions regarding the risk of sudden cardiac death in different types of heart failure patients, but poses several new questions that need to be explored,” said corresponding study author Ilan Goldenberg, M.D., research associate professor of Medicine in the Cardiology Division. “Why do obese heart failure patients see a risk advantage? Why do normal weight patients have a significantly different risk profile than those who are slightly overweight? These are important questions that may have treatment implications in the future.”

To reach the conclusion, researchers at the University’s Heart Research Follow-Up Program examined the risk of sudden cardiac death in 1,231 patients who had suffered at least one prior heart attack and had been diagnosed with a low ejection fraction, a measurement of how much blood is pumped from the heart with each beat. Their analysis found that decreased BMI or body mass index was associated with a large increase in the risk of sudden cardiac death. These findings highlight the “obesity paradox,” a phenomenon long recognized by cardiologists that, once afflicted, obese heart failure patients fare better than their slimmer counterparts.

“When we started this study we were hoping the data would disprove the obesity paradox,” said Bonnie Choy, co-lead author and a second year medical student at the University’s School of Medicine and Dentistry. “Our study is the first to create and analyze subcategories within non-obese patients, looking at overweight, normal and underweight patients, but even with this advanced analysis we still the saw an inverse relationship between BMI and sudden cardiac death.” (ANI)

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Scientists unveil biological process that spurs blood vessels growth

September 15, 2009 By Leave a Comment

Washington, Sept 15 (ANI): In a novel study, scientists from University of North Carolina and the College of Arts and Sciences have identified a novel mechanism that triggers blood vessel growth.

They have found that vascular networks form and expand by “sprouting” similar to the way trees grow new branches.

The process allows fresh oxygen and nutrients to be delivered to tissues, whether in a developing embryo or a cancerous tumour.

Earlier, scientists believed that the molecular signals to form new sprouts came from outside the vessel.

However, the new study has shown that signals can also come from within the blood vessel, pushing new blood vessel sprouts outward.

While analysing mouse embryonic stem cells and mouse retinas, the researchers found that defects in a protein called Flt-1 lead to abnormal sprouts and poor vessel networks.

Other research recently showed that levels of Flt-1 protein are particularly low in the dilated and leaky blood vessels that supply tumours with oxygen.

“The blood vessels themselves seem to participate in the process guiding the formation of the vascular network,” said senior study author Dr Victoria L. Bautch, professor of biology at UNC.

“They do not just passively sit there getting acted upon by signals coming from the outside in. Rather, they produce internal cues that interact with external cues to grow,” she added.

The growth of new blood vessels can be stimulated by cascades of events within the cell – known as pathways – the most notable of which centers around the three proteins Flt-1, Flk-1 and VEGF.

During the study, the researchers mixed two different types of mouse embryonic stem cells – one batch with normal Flt-1 protein levels, the other with no Flt-1 protein.

They found that the genetic makeup of the area at the base of the sprout – rather than at the sprout itself – determined whether the sprout behaved normally or abnormally.

“The cells on each side of sprout produce and send out the soluble form of the protein, blocking the sprout from forming anywhere but in one spot and in one direction,” says Bautch. “

So when the sprout first forms, instead of flopping back onto its parent vessel, it has a corridor to push it forward away from the parent,” she added.

The findings have been published in the journal Developmental Cell. (ANI)

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Your bathroom showers are hazardous to health

September 15, 2009 By Leave a Comment

Washington, September 15 (ANI): That invigorating relief and good cleansing from daily bathroom showers may bring along a face full of potentially pathogenic bacteria, warn researchers at the University of Colorado at Boulder.

Using high-tech instruments and lab methods, the researchers analysed roughly 50 showerheads from nine cities in seven states that included New York City, Chicago and Denver.

CU-Boulder Distinguished Professor Norman Pace, lead study author, says that about 30 percent of the devices were found to harbour significant levels of Mycobacterium avium, a pathogen linked to pulmonary disease that most often infects people with compromised immune systems, but which can occasionally infect healthy people.

The study showed that some M. avium and related pathogens were clumped together in slimy “biofilms” that clung to the inside of showerheads at more than 100 times the “background” levels of municipal water.

“If you are getting a face full of water when you first turn your shower on, that means you are probably getting a particularly high load of Mycobacterium avium, which may not be too healthy,” Pace said.

He pointed out that research at National Jewish Hospital in Denver indicated that increases in pulmonary infections in the US in recent decades from so-called “non-tuberculosis” mycobacteria species, such as M. avium, could be attributed to people taking more showers and fewer baths.

He said that water spurting from showerheads could distribute pathogen-filled droplets that suspend themselves in the air, and could easily be inhaled into the deepest parts of the lungs.

“There have been some precedents for concern regarding pathogens and showerheads. But until this study we did not know just how much concern,” said Pace.

In Denver, according to the researcher, one showerhead with high loads of Mycobacterium gordonae was cleaned with a bleach solution in an attempt to eradicate it, but tests conducted several months later showed that the bleach treatment ironically caused a three-fold increase in the pathogen, indicating a general resistance of mycobacteria species to chlorine.

Ask Pace whether it is dangerous to take showers, and he says: “Probably not, if your immune system is not compromised in some way. But it’s like anything else-there is a risk associated with it.”

He stresses that plastic showerheads appear to “load up” with more pathogen-enriched biofilms, and thus metal showerheads may be a good alternative.

“There are lessons to be learned here in terms of how we handle and monitor water. Water monitoring in this country is frankly archaic. The tools now exist to monitor it far more accurately and far less expensively that what is routinely being done today,” said Pace.

A research article on his study has been published in the online edition of the Proceedings of the National Academy of Sciences. (ANI)

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