Tuesday, June 30, 2009
Stimulant medications, such as Ritalin and Adderall, are the accepted treatment to stem hyperactivity in children with attention deficit-hyperactive disorder (ADHD) and improve their behavior.
Now a recent review of research by University at Buffalo pediatric psychologists suggests that such medication, or the assumption of medication, may produce a placebo effect -- not in the children, but in their teachers, parents or other adults who evaluate them.
A placebo effect is a positive change in symptoms or behavior after a patient receives a "fake" medication or procedure; in other words, the belief can become the medicine. In this case, the review suggested that when caregivers believed their ADHD patients were receiving ADHD medication, they tended to view those children more favorably and treat them more positively, whether or not medication was actually involved.
"The act of administering medication, or thinking a child has received medication, may induce positive expectancies in parents and teachers about the effects of that medication, which may, in turn, influence how parents and teachers evaluate and behave toward children with ADHD," said UB researcher Daniel A. Waschbusch, Ph.D., lead author of the review.
"We speculate that the perception that a child is receiving ADHD medication may bring about a shift in attitude in a teacher or caregiver. They may have a more positive view of the child, which could create a better relationship. They may praise the child more, which may induce better behavior."
Such a placebo effect in caregivers could have both good and not-so-good results, Waschbusch added. "If teachers treat children more positively if they think they are on medication, that is a good thing. But if the child's medication is increased because caregivers think it is effective, that may not be a good thing."
Waschbusch is an associate professor of psychology in the Department of Pediatrics at UB and conducts his research in UB's Center for Children and Families. The study was published in the Journal of Developmental & Behavioral Pediatrics.
Waschbusch and colleagues reviewed existing studies that evaluated whether placebos produce significant changes in children with ADHD and assessed four possible ways placebos could have an effect:
- Through the child's expectations of a change -- The analysis showed that any change in children's behavior was a direct result of the medication, not the expectation.
- By producing changes in how caregivers perceive children with ADHD when they think they are on medication -- The researchers determined the studies suggested that this may be a viable mechanism for the placebo effect.
- By producing changes in how caregivers behave toward children with ADHD who they think are on medication, which in turn, could produce changes in the child -- The analysis supported this hypothesis.
- Placebos may operate through classical conditioning. "For example," explained Waschbusch, "if a parent routinely gives their child active medication in pill form and then sees their child's behavior immediately improve, they will likely learn to connect administering a pill with improved child behavior. This learned connection could then be generalized to administering a placebo pill."
Waschbusch said the next step in this investigation could be a study that observes parents and children interacting under three different conditions: after children received a pill with real medication, after children received a pill with fake medication (a placebo) and after children didn't receive any pill.
"Comparing these conditions would provide information about the effects of actual medication relative to just getting a placebo," he said.
Are There Placebo Effects in the Medication Treatment of Children With Attention-Deficit Hyperactivity Disorder?
Waschbusch, Daniel A. PhD; Pelham, William E. Jr PhD; Waxmonsky, James MD; Johnston, Charlotte PhD
Journal of Developmental & Behavioral Pediatrics: April 2009 - Volume 30 - Issue 2 - pp 158-168doi: 10.1097/DBP.0b013e31819f1c15
Link to JDBP abstract
Scientists know that some cancers are triggered by viruses, which take over cellular systems and cause uncontrolled cell growth. Doctors – and patients who get shingles late in life – have also known for many years that some viruses, particularly the herpes virus, can lie dormant in a person's cells for long periods of time and then reactivate, causing disease. These viruses also cause significant disease in immunosuppressed people and those living with HIV/AIDS.
A recent study led by Blossom Damania, Ph.D., associate professor of microbiology and immunology at the University of North Carolina at Chapel Hill, focuses on the intersection of these two scientific puzzles, resulting in new discoveries about how one herpesvirus known to cause cancer may reactivate when the infected cell senses another type of virus entering it.
Damania, who is also a member of the UNC Lineberger Comprehensive Cancer Center, focused on Kaposi's sarcoma-associated herpesvirus (KSHV), an agent associated with Kaposi's sarcoma, primary effusion lymphoma and another syndrome called Castleman's disease.
"We hypothesized that a secondary viral infection could serve as the trigger for KSHV, so we took cells infected with KSHV and activated immune receptor proteins called toll-like receptors that are present on the body's cells. Toll-like receptors are the guardians of the cell and essentially function to alert the cell to the presence of an intruder. These proteins act as an alarm system to tell the cell that a foreign organism is trying to enter it," said Damania.
Ten human toll-like receptors have been identified by scientists thus far, but the UNC team found that activation of only two of them, TLR7 and TLR8, reactivated the virus, allowing it to reproduce itself. The cells self-destruct in an attempt to kill the virus, but by the time the cell dies, the virus has already replicated and escaped, moving on to infect other cells in the body.
"This is a very exciting finding because it helps us better understand how a latent virus can suddenly reactivate, replicating and spreading throughout the body. Additionally, since Kaposi's sarcoma is a cancer that is associated with this phase of viral infection, it is plausible that the virus' activation and replication may eventually lead to the development of Kaposi's sarcoma in an infected individual.
"Laboratory experiments in a controlled research environment often do not reflect the real world, where we are constantly exposed to many different environmental factors and other microorganisms. This finding is an important reminder that multiple factors are involved in causing disease," she added.
Toll-like receptor signaling controls reactivation of KSHV from latency
Sean M. Gregory, John A. West, Patrick J. Dillon, Chelsey Hilscher, Dirk P. Dittmer, and Blossom Damania
Proceedings of the National Academy of Sciences (PNAS) published online before print June 29, 2009, doi:10.1073/pnas.0905316106
Link to PNAS abstract
Levels of adherence to HIV treatment differ significantly between racial groups, US investigators report in the online edition of the Journal of Acquired Immune Deficiency Syndromes. They also found that the factors affecting adherence differed between racial groups. Furthermore, different levels of adherence were seen within racial groups according to ethnicity.
“Adherence is multifactorial and varies significantly by race and ethnicity”, comment the investigators.
A number of factors can have an impact on a patient’s ability to adhere to their HIV treatment. These can include health status, side-effects, socioeconomic circumstances, and drug and alcohol use.
Although some research has suggested that racial minorities have lower rates of adherence, there is little information on possible reasons for this.
Furthermore, black and Hispanic are often used as separate, uniform categories without taking into account the important ethnic differences that can exist within these groups.
Both blacks and Hispanics are disproportionately affected by HIV in the US. Therefore investigators from the Multicenter AIDS Cohort Study investigated how adherence differs according to race and ethnicity, and the factors affecting adherence.
“We found that blacks and Hispanics are more likely to be nonadherent and that individuals from Central and South America and the Caribbean are especially at risk of nonadherence”, write the authors. They conclude, “further adherence research and interventions should focus not solely on racial groups but also the ethnic differences within groups.”
Evaluation of adherence and factors affecting adherence to combination antiretroviral therapy among white, Hispanic, and black men in the MACS cohort.
Detels, Roger MD, MS et al.
Journal of Acquired Immune Deficiency Syndromes (online edition), 2009 doi: 10.1097/QAI.0b013e3181ab6d48.
Link to JAIDS abstract
A team of Harvard scientists has taken an important first step toward the development of new treatments to help people with HIV battle Mycobacterium tuberculosis (TB) infection. In their report, appearing in the July 2009 print issue of the Journal of Leukocyte Biology they describe how HIV interferes with the cellular and molecular mechanisms used by the lungs to fight TB infection.
This information is crucial for researchers developing treatments to help people with HIV prevent or recover from TB infection.
"HIV/TB co-infection is a critical global health problem, especially in developing countries," said Naimish Patel, M.D., lead researcher on the study and Instructor of Medicine at Beth Israel Deaconess Medical Center and Harvard Medical School. "We hope that these findings will lead to further studies and possible new therapies for treating or preventing tuberculosis in HIV disease."
Patel and colleagues made their discovery by extracting immune cells called "alveolar macrophages" from the lungs of otherwise healthy, asymptomatic HIV-positive patients as well as from people who did not have HIV. In people who are HIV-positive, the macrophages have a decreased response to the TB bacterium when compared to people who did not have HIV. To learn why, the scientists examined lung specimens from the HIV-positive patients and found increased levels of a molecule called IL-10, which elevated the amount of a protein called "BCL-3" in alveolar macrophages and that reduced their ability to ward off TB infection.
"HIV and TB represent two of the most significant health challenges in human history and the combination of the two infections is particularly devastating because HIV dramatically increases the severity of TB infection," said John Wherry, Ph.D., Deputy Editor of the Journal of Leukocyte Biology, "There are still many unknowns about how HIV reduces the ability of the body to combat other infections. This study sheds light on co-infection with HIV and TB, which up to this point, has perplexed scientists and physicians alike."
Impaired M. tuberculosis-mediated apoptosis in alveolar macrophages from HIV persons: potential role of IL-10 and BCL-3.
Naimish R. Patel et al.
Journal of Leukocyte Biology, 2009; 86 (1): 53 DOI: 10.1189/JLB.0908574
Link to JLB abstract
Despite recent declines in cigarette use in the U.S., nicotine dependence has remained steady among adults and has actually increased among some groups. The finding by researchers at Columbia University Mailman School of Public Health suggests that public health initiatives have been far more successful in preventing Americans from taking up smoking than in persuading hard-core smokers to stop.
Previous studies have found that since the 1964 U.S. Surgeon General report, the number of people who smoke cigarettes has declined. The Mailman School of Public Health study takes this research a step further by distinguishing occasional smokers from heavy smokers. "Regular, heavy cigarette use frequently characterizes nicotine dependence and is the pattern of use thought to be the most detrimental to health and longevity, but it has not been addressed in previous estimates of the decline in smoking prevalence," says Renee Goodwin, PhD, associate professor of Epidemiology at the Mailman School of Public Health and principal investigator of the study. "Rather, earlier research mainly addressed tobacco use or cigarette smoking per se rather than examining the frequency and duration of cigarette use in detail."
The new study finds not only that the number of nicotine-addicted Americans has held steady over the past several decades, but also that the proportion of cigarette smokers who are addicted to nicotine nowadays is greater than in previous generations. Dr. Goodwin cites a possible explanation for this latter finding. She suggests that fewer people are taking up smoking, perhaps because of anti-cigarette campaigns, leaving the ranks of current smokers filled with the nicotine dependent.
Another factor that has changed dramatically in the epidemiology of tobacco consumption and dependence over the past several decades is gender. Smoking has been far more common among men than among women for most of the past forty years, though recent evidence suggests that the gender gap has narrowed, and the current study finds increases in smoking among women in several recent generations.
It is also thought that socioeconomic status is a factor in cigarette use. The current study finds that younger women living in poverty had the highest rates of nicotine dependence, compared with older generations, and those not living in poverty. This suggests that despite increases in taxes and smoking costs, those most vulnerable are still heavily affected.
"Passage of this month's law governing the regulation of tobacco products and its focus on preventing smoking initiation among children is important and timely as our findings suggest that the number of people who still smoke is considerable," observes Dr. Goodwin. "Hopefully this legislation will help reduce the number addicted to nicotine in future generations since never smoking is the only sure way to prevent the development of nicotine dependence." "Given the mounting evidence that nicotine dependence plays a crucial role in smoking patterns, there is no question that future studies on curbing cigarette use need to take nicotine dependence into account."
Goodwin et al. Changes in Cigarette Use and Nicotine Dependence in the United States: Evidence from the 2001-2002 Wave of the National Epidemiologic Survey of Alcoholism and Related Conditions.
Renee D. Goodwin, Katherine M. Keyes, Deborah S. Hasin
American Journal of Public Health, August 2009 print edition DOI: 10.2105/AJPH.2007.127886
Link to AJPH abstract
The influenza virus that wreaked worldwide havoc in 1918-1919 founded a viral dynasty that persists to this day, according to scientists from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.
In an article published online on June 29 by the New England Journal of Medicine, authors Anthony S. Fauci, M.D., Jeffery K. Taubenberger, M.D., Ph.D., and David M. Morens, M.D., argue that we have lived in an influenza pandemic era since 1918, and they describe how the novel 2009 H1N1 virus now circling the globe is yet another manifestation of this enduring viral family.
"The 1918-1919 influenza pandemic was a defining event in the history of public health," says NIAID Director Dr. Fauci. "The legacy of that pandemic lives on in many ways, including the fact that the descendents of the 1918 virus have continued to circulate for nine decades."
Influenza viruses have eight genes, two of which code for virus surface proteins—hemagglutinin (H) and neuraminidase (N)—that allow the virus to enter a host cell and spread from cell to cell. There are 16 H subtypes and 9 N subtypes, and, therefore, 144 possible HN combinations. However, only three (H1N1, H2N2 and H3N2) have ever been found in influenza viruses that are fully adapted to infect humans. Other combinations, such as avian influenza H5N1, occasionally infect people, but they are bird viruses, not human viruses.
"The eight influenza genes can be thought of as players on a team: Certain combinations of players may arise through chance and endow the virus with new abilities, such as the ability to infect a new type of host," says Dr. Morens, Senior Advisor to the NIAID Director. That is likely what happened to spark the 1918 pandemic, he adds. Scientists have shown that the founding virus was an avian-like virus. The virus had a novel set of eight genes and—through still-unknown mechanisms—gained the ability to infect people and spread readily from person to person.
Not only did the 1918 H1N1 virus set off an explosive pandemic in which tens of millions died, during the pandemic the virus was transmitted from humans to pigs, where—as it does in people—it continues to evolve to this day. "Ever since 1918, this tenacious virus has drawn on a bag of evolutionary tricks to survive in one form or another…and to spawn a host of novel progeny viruses with novel gene constellations, through the periodic importation or exportation of viral genes," write the NIAID authors.
"All human-adapted influenza A viruses of today—both seasonal variations and those that caused more dramatic pandemics—are descendents, direct or indirect, of that founding virus," notes Dr. Taubenberger, Senior Investigator in NIAID's Laboratory of Infectious Diseases. "Thus we can be said to be living in a pandemic era that began in 1918."
How exactly do new influenza gene teams make the leap from aquatic birds to a new host, such as people or other mammals? What factors determine whether infection in a new host yields a dead-end infection or sustained, human-to-human transmission, as happened in 1918? Research on such topics is intense, but at this time definitive answers remain elusive, notes Dr. Morens.
It is known that the human immune system mounts a defense against the influenza virus's H and N proteins, primarily in the form of antibodies. But as population-wide immunity to any new variant of flu arises, the virus reacts by changing in large and small ways that make it more difficult for antibodies to recognize it. For nearly a century, then, the immune system has been engaged in a complicated pas de deux with the 1918 influenza virus and its progeny, say the NIAID authors. The partners in this dance are linked in an endless effort to take the lead from the other.
While the dynasty founded by the virus of 1918 shows little evidence of being overthrown, the NIAID authors note that there may be some cause for optimism. When viewed through a long lens of many decades, it does appear that successive pandemics and outbreaks caused by later generations of the 1918 influenza dynasty are decreasing in severity, notes Dr. Morens. This is due in part to advances in medicine and public health measures, he says, but this trend also may reflect viral evolutionary pathways that favor increases in the virus's ability to spread from host to host, combined with decreases in its tendency to kill those hosts.
"Although we must be prepared to deal with the possibility of a new and clinically severe influenza pandemic caused by an entirely new virus, we must also understand in greater depth, and continue to explore, the determinants and dynamics of the pandemic era in which we live," conclude the authors.
The persistent legacy of the 1918 influenza virus.
David M. Morens, M.D., Jeffery K. Taubenberger, M.D., Ph.D., and Anthony S. Fauci, M.D.
New England Journal of Medicine, published on line June 29, 2009 (10.1056/NEJMp0904819)
Link to NEJM abstract
This is one of the articles also posted at the New England Journal of Medicine’s H1N1 Influenza Center
Link to h1n1.nejm.org/
Monday, June 29, 2009
Two Indiana University studies conducted among nationally representative samples of adult American men and women show that vibrator use during sexual interactions is common, with use being reported by approximately 53 percent of women and 45 percent of men ages 18 to 60. Not only is vibrator use common, but the two studies also show that vibrator use is associated with more positive sexual function and being more proactive in caring for one's sexual health.
The studies, led by researchers at the Center for Sexual Health Promotion in IU's School of Health, Physical Education and Recreation, are the first to publish data about vibrator use from nationally representative samples of the U.S. population. This lack of data has existed despite a longstanding practice by many physicians and therapists to recommend vibrator use to help treat sexual dysfunctions or to improve sexual enjoyment.
One study surveyed women. The other surveyed men. Both were published by the Journal of Sexual Medicine, a leading peer-reviewed journal in the area of urology and sexual health.
"The study about women's vibrator use affirms what many doctors and therapists have known for decades -- that vibrator use is common, it's linked to positive sexual function such as desire and ease of orgasm, and it's rarely associated with any side effects," said Debby Herbenick, associate director of the Center for Sexual Health Promotion.
Michael Reece, director of the Center for Sexual Health Promotion, said the studies are important for the contributions they make to an understanding of the sexual behaviors and sexual health of adults in today's society.
"The study about male vibrator use is additionally important because it shows that vibrator use is also common among men, something that has not been documented before," Reece said. "Also, both studies help us to further understand the way in which American consumers are turning to the marketplace for products that promote their sexual health, and that has important economic implications."
Here are some of the findings from the studies, which involve survey responses from 2,056 women and 1,047 men ages 18-60.
· More than half of the women (52.5 percent) had used a vibrator with nearly one in four having done so in the past month.
· Vibrator users were significantly more likely to have had a gynecological exam during the past year and to have performed genital self-examination during the previous month.
· Vibrator use was positively related to several aspects of sexual function (desire, arousal, lubrication, orgasm, pain and overall function) with recent vibrator users scoring themselves higher on most sexual function domains, suggesting more positive sexual function.
· Most women (71.5 percent) reported having never experienced any side effects associated with vibrator use. Those side effects that were reported were typically rare and of a short duration.
· The prevalence of men who had incorporated a vibrator into sexual activities during their lives was 44.8 percent, with no statistical differences between the rates of vibrator use between men who identified as heterosexual and those who identified as gay or bisexual.
· Heterosexual men most commonly reported having used vibrators during foreplay or intercourse with a female partner, with 91 percent of those who had used a vibrator reporting that they had done so during such activities with women.
· Of men who have used vibrators, 10 percent had done so in the past month, 14.2 percent in the past year and 20.5 percent more than one year ago.
· Men who reported having used vibrators, particularly those with more recent use, were more likely to report participation in sexual health promoting behaviors, such as testicular self-exam.
· Men who had used vibrators recently also scored themselves higher on four of the five domains of sexual function, as measured by the International Index of Erectile Function (erectile function, intercourse satisfaction, orgasmic function and sexual desire).
Prevalence and Characteristics of Vibrator Use by Men in the United States.
Michael Reece, PhD, MPH,et al.
Journal of Sexual Medicine, 2009; 6 (7): 1867 - 1874 DOI: 10.1111/j.1743-6109.2009.01290.x
Link to JSM abstract
Prevalence and Characteristics of Vibrator Use by Women in the United States: Results from a Nationally Representative Study.
Debra Herbenick, PhD, MPH et al.
Journal of Sexual Medicine, 2009; 6 (7): 1857 - 1866 DOI: 10.1111/j.1743-6109.2009.01318.x
Link to JSM abstract
University of Minnesota Medical School researcher Iris Borowsky, M.D., Ph.D., and colleagues found that one in seven adolescents believe that it is highly likely that they will die before age 35, and this belief predicted that the adolescents' would engage in risky behaviors.
Borowsky and colleagues analyzed data collected by the National Longitudinal Study of Adolescent Health, a nationally representative sample of more than 20,000 youth in grades 7 through 12 during three separate study years. In the first set of interviews, nearly 15 percent of adolescents predicted they had a 50/50 chance or less of living to age 35. Those who engaged in risky behaviors such as illicit drug use, suicide attempts, fighting, or unsafe sexual activity in the first year were more likely in subsequent years to believe they would die at a young age. Vice versa, those who predicted that they'd die young during the first interview were more likely in later years to begin engaging in these same risky behaviors and have poor health outcomes. Notably, these teens were significantly more likely to be diagnosed with HIV/AIDS just six years later, regardless of their sexual preference.
"While conventional wisdom says that teens engage in risky behaviors because they feel invulnerable to harm, this study suggests that in some cases, teens take risks because they overestimate their vulnerability, specifically their risk of dying," Borowsky said. "These youth may take risks because they feel hopeless and figure that not much is at stake."
Nearly 25 percent of youth living in households that receive public assistance and more than 29 percent of American-Indian, 26 percent of African-American, 21 percent of Hispanic, and 15 percent of Asian youth reported believing they would die young—compared to just 10 percent of their Caucasian peers.
"Our findings reinforce the importance of instilling a sense of hope and optimism in youth," Borowsky said. "Strong connections with parents, families, and schools, as well as positive media messages, are likely important factors in developing an optimistic outlook for young people."
She also notes that study findings support physician screening of adolescents for this perceived risk of early death. "This unusually common pessimistic view of the future is a powerful marker for high-risk status and thus deserves attention."
There was no significant relationship between perceived risk of dying before age 35 and actual death from all causes during the six year study period.
Health Status and Behavioral Outcomes for Youth Who Anticipate a High Likelihood of Early Death.
Iris Wagman Borowsky, MD, PhD, Marjorie Ireland, PhD and Michael D. Resnick, PhD Pediatrics, July, 2009; 124: e81-e88 (doi:10.1542/10.1542/peds.2008-3425)
Link to Pediatrics abstract
Professional cyclists should consider freezing their sperm before embarking on their careers, say researchers. They found sperm quality drops dramatically with rigorous training.
The Spanish study of top triathletes found those who cover more than 186 miles (300km) a week on their bikes have less than 4% normal looking sperm.
At such levels, men would have "significant fertility problems", the European Society of Human Reproduction and Embryology heard.
However, a UK expert said the average man cycling to work would be unlikely to suffer fertility problems because of their time in the saddle.
Study leader Professor Diana Vaamonde, from University of Cordoba Medical School in Spain said other studies had shown very high levels of exercise affected fertility in both men and women.
In the latest study, 15 triathletes with an average age of 33, were asked not to have sex for three days before giving a sperm sample.
When the results were compared with their training routines, only cycling - not swimming or running - was linked with sperm quality.
All of the men - who had been training for an average of nine times a week for eight years - had less than 10% of normal looking sperm, compared with the 15-20% seen in the most fertile men.
In those who managed more than 186 miles a week on their bikes, the proportion of sperm that was the correct size and shape had fallen to 4%, the point at which men may struggle to conceive without fertility treatment.
Heat from wearing tight clothing, friction of the testes against the saddle and stresses on the body from the sheer amounts of energy needed to do such rigorous exercise, could all contribute to poor sperm quality, said Professor Vaamonde.
The team are doing further research work in how cycling may affect metabolic processes in the body which lead to the development of abnormal sperm.
She added it was unclear whether sperm quality would improve if men retired from the sport but that after years of wear and tear this was unlikely.
"Something which could be done would be to have their sperm frozen but when they start training they do not realize what damage can be done to their sperm."
Ways of protecting cyclists against fertility problems should also be researched she said.
"Depending on the mechanism leading to creation of abnormal sperm, these could include giving antioxidants and modifying training regimes to all for recovery."
ESHRE PGD Consortium data collection IX: cycles from January to December 2006 with pregnancy follow-up to October 2007
V. Goossens et al
Human Reproduction, doi:10.1093/humrep/dep059
Link to Human Rep abstract
Black gay men have less choice when it comes to sexual partners than other groups and, as a result, their sexual networks are closely knit. These tightly interconnected networks make the rapid spread of HIV more likely. In a study looking at social and sexual mixing between ethnic groups in men who have sex with men, H. Fisher Raymond and Willi McFarland, from the San Francisco Department of Public Health, show that social barriers faced by Black gay men may have a serious impact on their health and well-being.
In the US, there is a disproportionate burden of HIV infection in Black Americans, who accounted for nearly half of all HIV/AIDS cases diagnosed in 2006 – four times the national average. Raymond and McFarland’s research looks at the current levels of sexual mixing between racial and ethnic groups of men who have sex with men in San Francisco, and identifies reasons that underlie these sexual mixing patterns.
A total of 1,142 gay men took part in computer-assisted interviews. They were asked about their own ethnicity, the race of their sexual partners in the last six months, their perception of how easy it is to meet sexual partners of different ethnicities, where they meet sexual partners, their view of HIV infection risk and the predominant race of their network of friends.
Black gay men are the least preferred of sexual partners by other races. Black men are perceived to be riskier to have sex with, which can lead to men of other races avoiding Black men as sexual partners. They are also perceived as less welcome in the common social venues of gay men in San Francisco. As a result, Black men are three times more likely to have sexual partners that are also Black, than would be expected by chance alone.
In the authors’ view, the combination of attitudes on the part of non-Black gay men, friendships and social networks that are less likely to include Blacks, and the environments found in gay venues serve to separate Black gay men from other groups. Consequently, the sexual networks of Blacks are pushed to be more highly interconnected than other groups, with the potential for a more rapid spread of HIV and a higher sustained prevalence of infection among Black gay men.
The authors conclude: “The racial disparity in HIV observed for more than a decade will not disappear until the challenges posed by a legacy of racism towards Blacks in the US are addressed.”
Racial Mixing and HIV Risk Among Men Who Have Sex with Men.
H. Fisher Raymond and Willi McFarland
AIDS and Behavior, 2009; DOI: 10.1007/s10461-009-9574-6
Link to AIDS and Behavior abstract
Researchers from EnGeneIC, an Australian firm from the suburbs of Sydney, have developed a cancer treatment that so far performed remarkably well in animal tests. By encompassing toxins in "minicells", made off of chunks of bacteria cell membrane harvested during division, they were able to deliver chemicals precisely to neoplasm sites while helping bypass the tumor's natural defenses.
Sydney Morning Herald reports:
In the first step, the mini-cells were filled with tiny pieces of genetic material, called short interfering RNA molecules, and injected into mice with drug resistant colon, breast and uterine tumors.
The molecules switched off the gene in the tumors that made them resistant to chemotherapy.
In a second-wave attack a week later mini-cells filled with the cancer drug were injected, and the tumor cells were killed with much smaller doses of the toxic agent than normal, avoiding harmful side effects.
All the treated mice, which had been transplanted with aggressive human cancers, survived and their tumors shrank or growth was halted.
Sequential treatment of drug-resistant tumors with targeted minicells containing siRNA or a cytotoxic drug
Jennifer A MacDiarmid et al
Nature Biotechnology Published online: 28 June 2009 | doi:10.1038/nbt.1547
Link to Nature Bio abstract
Experts have reported the first case of swine flu that is resistant to tamiflu - the main drug being used to fight the pandemic. Roche Holding AG confirmed a patient with H1N1 influenza in Denmark showed resistance to the antiviral drug. Experts have been using tamiflu, also known as oseltamivir, in a bid to stop the H1N1 spreading in communities.
If taken early, it ensures that symptoms are mild and reduces the chance of a victim giving the illness to someone else.
David Reddy, company executive, said it was not unexpected given that common seasonal flu could do the same.
Mr Reddy stressed that there were no signs of a tamiflu-resistant strain of H1N1 circulating in the community. Experts fear if this were to happen, it could render tamiflu ineffective
This is in contrast to seasonal H1N1 flu where a Tamiflu resistant strain emerged last year and is now widely circulating.
Another antiviral drug, called zanamivir or Relenza, made by GlaxoSmithKline, is also effective against swine flu.
Sunday, June 28, 2009
Science Daily (June 25, 2009)
Patriotic Music May Close Minds, Children's Music May Open Them
The words to "Itsy Bitsy Spider" tell a simple story about an arachnid and a spout, but simply recalling the lines could initiate an unintentional attitude.
That's the focus of research by Kansas State University's Eduardo Alvarado, sophomore in pre-law, who is looking at the behaviors elicited from the musical lyrics of common songs.
Alvarado is working with Donald Saucier, associate professor of psychology at K-State to study the effects priming can have on behavior by looking at the positive and negative responses stimulated from music lyrics from a variety of song categories, including patriotic and Christmas songs. Priming, he said, is when someone is exposed to a certain environment and their subconscious is activated, and then they tend to act in accordance with that environment without deliberate intent. Priming can manipulate behavior; if someone witnesses violent behavior, they would likely behave more violently.
"One of the key implications is that behaviors may be malleable in the sense that many individuals have the capacity for similar reactions in social situations," Saucier said. "Relatively small-scale primes may activate certain reactions, and these may be pro-social or anti-social depending on the context."
Alvarado said the researchers wanted to see if certain musical lyrics activated a pro-social response, which is a positive feeling like empathy, or an anti-social response, which is a negative feeling like aggression. Study participants had to complete a survey and do a lyrics exercise. For the lyrics exercise, participants had to fill in missing lyrics for different songs.
The songs involved in the study were patriotic songs, such as "The Star-Spangled Banner"; secular Christmas songs, such as "Rudolph the Red-Nosed Reindeer"; religious Christmas songs, such as "O Holy Night"; and neutral songs, such as "Itsy Bitsy Spider."
Participants filled out a survey that asked questions about their religion and their attitudes toward other cultures and diversity. Half of the participants were asked to complete the survey before the lyric exercise, and the other half completed the survey after the exercise.
Alvarado said the researchers assume people act similarly to primes, and they looked overall at the surveys to see if there was a change in the responses before and after completing the lyrics exercise. They wanted to see if the songs created a pro-social or an anti-social response. He said the preliminary findings showed that the patriotic songs had a negative effect on the participants, as shown through their responses to the survey's questions about other cultures and diversity. The patriotic songs made the participants close-minded and prejudiced.
"Once they were in a patriotic point of view, they were less empathetic," Alvarado said. "They didn't put themselves in other people's perspective."
Though songs like "Itsy Bitsy Spider" and "Row, Row, Row Your Boat" were meant to be neutral primes, the researchers found that they stimulated a pro-social response.
"You wouldn't think that those songs were going to put people in a certain mind frame, but they do activate a certain attitude," Alvarado said. "We found it made people more accepting and more empathetic. The reason for this we think is because we used to listen to these songs when we were little and they kind of activate childhood happiness."
Fireworks are a popular way to celebrate the Fourth of July, whether shooting them off from the backyard or watching a professional display.
While there are many reasons why fireworks are so enjoyed on Independence Day, tradition and their dangerous side could be part of their attraction for some of us, according to two Kansas State University psychologists.
Holidays, weddings and birthdays are occasions that tend to bring out the most traditional side of people, said Richard Harris, K-State professor of psychology.
"This is particularly true if people have strong memories of celebrating a holiday in a particular way in their childhood," Harris said. "People are strongly drawn to recreate that 'safe' childhood holiday activity. People who might never seek out a fireworks display other times might find that important to do on Independence Day. People who remember enjoying setting off fireworks themselves as children will want to do that as adults or at least help their kids do it, and as such, perpetuate these memories."
If someone has no such memories, they won't respond that way, Harris said.
"For example, I grew up somewhere where individual fireworks were not allowed -- or even available as far as I knew -- so I never did that. I've always thought of them as dangerous and really didn't want my kids to have them," he said.
"Another example of the power of traditions is that even many very nontraditional people will want a traditional wedding and may surprise themselves and friends as to how important some traditional wedding trappings might be to them," Harris said. "Similarly, many people feel that Christmas should be spent with family -- even family you don't necessarily feel that close to or whose company you would not seek out at other times. Most people want turkey for Thanksgiving -- even if they don't particularly like turkey."
Fireworks also are explosives and can be dangerous, which can add to their appeal to some people, said Mary Cain, associate professor of psychology at K-State.
"Engaging in risky behaviors is very reinforcing for people," Cain said. "For some, it can cause release of a chemical in the brain that helps people feel good. The chemical is a neurotransmitter called dopamine and it is released when we engage in behaviors we enjoy, such as eating, drinking, sex, etc. Some people release dopamine when they engage in risky behaviors.
"Individuals vary in how much they find risky behavior reinforcing. People who are high sensations seekers enjoy risky behaviors more and seek them out. In addition to fireworks, they enjoy things that are novel and complex, such as roller coasters, skydiving and driving fast," she said. "On the other hand, low sensation seekers do not enjoy these activities and will likely avoid them. When we look at the dopamine system of high and low sensation seekers, high sensation seekers have differences in their dopamine system and have more activation of the dopamine system when they are presented with new and complex stimuli."
Cain said another reason we may enjoy fireworks might be because they are only available for a few days of the year.
"If people had daily access to them, most would begin to find them boring, but given that our access is restricted, we find we may enjoy them more," she said. "In many states fireworks are illegal on the Fourth. For some, especially high sensation seekers, this may increase their appeal even more as using them becomes an even riskier behavior since they are illegal."
Saturday, June 27, 2009
According to a report published by an expert group for the International Scientific Forum of Home Hygiene, we must all share responsibility for preventing the spread of diseases such as swine flu, SARS, avian influenza, diarrhoeal and skin diseases, and even the common cold.
The swine flu scare has prompted some to say that we are over-reacting but it is important to look at the bigger picture - because the next new pathogens are always just around the corner. The regular emergence of new pathogenic strains, and their unpredictable behavior, means that sustained investment in effective strategies of mitigation and containment make absolute sense.
But if infections are to be kept in check, there needs to be a fundamental change in our approach to hygiene, with more emphasis being placed on empowering families to take on this responsibility.
Professor Sally Bloomfield of the London School of Hygiene & Tropical Medicine and one of the report's authors, comments: 'Although antibiotics and vaccines have given us unprecedented ability to prevent and treat killer diseases, hygiene is still fundamental to winning the battle against infectious disease in both developed and developing countries – and that's a job for all of us. This is not about shifting responsibility, it's about facing reality'.
The report indicates that a significant proportion of global infectious disease could be prevented through improved hygiene practice coupled with the provision of adequate water and sanitation. One of its key conclusions is that, if the burden of these diseases is to be contained in a manner which is economically sustainable, it must be a responsibility which is shared by all of us.
Information around hygiene is still too fragmented and confusing, however. For example, advice on preventing spread of colds and flu is very different from that on preventing diarrheal diseases. What is needed, argue the authors, is a less agency-centered approach, and one that is more family-centered, empowering parents to better protect themselves and their families against infection. Dr Elizabeth A Scott, also a co-author comments: 'The key to getting people to change their behavior is to find a way to make hygiene behavior more appealing and relevant by realigning it with other aspects of healthy living such as diet and exercise. People also need to understand that they can be proactive in protecting themselves and reducing their risk of acquiring an infection in their everyday lives'.
If we can prevent infections through good hygiene, we can also reduce the amount of antibiotics we need to prescribe, according to co-author Professor Martin Exner . Overprescription of antibiotics is the main cause of antibiotic resistance, which is threatening our ability to treat infections effectively when they occur.
In developing countries, the huge burden of hygiene and sanitation-related infectious diseases continue to be the most critical public health threat. Says co-author Professor KJ Nath: 'Much of the focus in developing countries is on investment in community water supply and sanitation in order to meet the Millennium Development Goals, but if the health benefits are to be realized, programs of hygiene promotion must be implemented in conjunction with improvements in water and sanitation'.
The global burden of hygiene-related diseases in relation to the home and community
Professor Sally F. Bloomfield, Professor Martin Exner, Professor Gaetano M. Fara, Professor Kumar Jyoti Nath, Dr Elizabeth A Scott, Carolien Van der Voorden
The International Scientific Forum on Home Hygiene June 2009
Link to the report [pdf]
UBC researchers have created the world's first animal laboratory experiment to successfully model human gambling. The advance will help scientists develop and test new treatments for gambling addictions, a devastating condition that affects millions worldwide.
In addition to showing that rats can "play the odds," the study finds that gambling decisions can be impaired or improved with drugs that affect brain dopamine and serotonin levels suggesting that these neurotransmitters may moderate gambling behavior.
"For most individuals, gambling is enjoyable and harmless, but for others, it is as destructive as being addicted to drugs," says Catharine Winstanley, an assistant professor in UBC's Dept. of Psychology, whose study was published June 17 in the Nature journal Neuropsychopharmacology.
"This new model is an important next step because the neurobiological basis of gambling is still poorly understood and few treatment options exist," adds Winstanley, noting that gamblers experience higher rates of divorce, suicide and crime than non-gamblers. "It brings us a step closer to the goal of drug-based treatments for people suffering from gambling disorders."
For the study, rats had a limited amount of time in which to choose between four gambling options which were associated with the delivery of different numbers of sugar pellets. If the animals won the gamble, they received the associated reward. However, if they lost, they experienced a time-out period during which reward could not be earned.
High-risk options offered more potential sugar pellets but also the possibility of more frequent and longer timeouts. Rats learned how to be successful gamblers, selecting the option with the optimum level of risk and reward to maximize their sugar pellet profits.
The study found that rodents treated with drugs that reduced their levels of serotonin levels – associated with impulse control in humans –dramatically reduced their ability to play the odds. A drug that reduced dopamine levels – associated with pleasure in humans – improved their ability to optimize profits. The findings are consistent with recent clinical findings in humans, helping to validate the technique as a model for studying human gambling behaviors.
Serotonergic and Dopaminergic Modulation of Gambling Behavior as Assessed Using a Novel Rat Gambling Task
Fiona D Zeeb, Trevor W Robbins, Catharine A Winstanley
Neuropsychopharmacology (17 June 2009) doi:10.1038/npp.2009.62
Link to Neuropsych article
President Barack Obama's signature on a bill this week to grant the Food and Drug Administration (FDA) regulatory authority over tobacco was historic, and represents a step in the march to eliminate tobacco use in this country by 2047, two national tobacco experts said on June 25.
Michael Fiore and Timothy Baker, director and associate director of the University of Wisconsin-Madison Center for Tobacco Research and Intervention (UW-CTRI) respectively, chart milestones in beating tobacco addiction and map a battle plan to eradicate tobacco use in the next few decades. The researchers analyzed data from the 1960s, when the first systemic tracking of smoking rates began, until the present.
"Numerous observers have claimed over time that tobacco use has plateaued and progress against its use has stalled," the authors write. "However, the remarkable decline in rates of tobacco use since the 1960s belies this claim and underscores the remarkable success of tobacco control efforts to date."
Data from the Centers for Disease Control and Prevention show adults smoking between 1965 and 2007 dropped by an average of one half of one percentage point per year, from 42 percent to the current rate of about 20 percent rate. While this rate of decline hasn't occurred each year, the overall decrease has been quite steady.
The two researchers urge a nationwide effort designed to accelerate the rate of decline over the next 50 years through:
- Substantial increases in federal and state tobacco excise taxes.
- A national clean-indoor air law.
- Elimination of nicotine from tobacco products.
- Funds for an aggressive mass media campaign to counter the tide of tobacco industry ads and sponsorships.
- A ban on tobacco advertising, promotion and sponsorship.
- Evidence-based counseling and medication for every smoker who wants to quit.
- Protecting young people, particularly those 17 and younger, from starting to smoke. Research shows that a major genetic risk for lifelong nicotine dependence can be suppressed if young people avoid daily smoking prior to age 17.
"The progress made in reducing tobacco use over the last 50 years should in no way temper our commitment to further reductions. Nor should that progress be interpreted to mean tobacco use is less toxic or that tobacco companies are now on the ropes. But, if appropriate steps are taken, a tobacco-free nation can be achieved within a few decades," Fiore says.
Past success has been born of:
- Tobacco tax increases.
- Enactment of clean-indoor air laws.
- Tobacco industry advertising restrictions.
- Tobacco product-labeling requirements.
- Policies that restrict youth access to tobacco products.
- Mass media campaigns.
- Increased availability and effectiveness of treatments to help current smokers quit.
In their article, Baker and Fiore called for FDA regulation of tobacco products to spur progress. That bill was signed into law on June 22, along with provisions that would further restrict tobacco industry targeting of kids, strengthen health warnings on tobacco packaging, require disclosure about what's in tobacco products and ban terms like "light" and "mild" to describe cigarettes.
Stealing a March in the 21st Century: Accelerating Progress in the 100-Year War Against Tobacco Addiction in the United States
Michael C. Fiore, MD, MPH and Timothy B. Baker, PhD
American Journal of Public Health, 2009; 99 (7): 1170 DOI: 10.2105/AJPH.2008.154559
Link to AJPH abstract
Social problems like bullying and stereotyping involve thoughts, feelings and reactions that resist change. New research shows that when students play active roles in virtual dramas their attitudes and behavior can change.
In 2006, a group of European educators, psychologists and IT specialists realized that emotionally driven problems, such as bullying, stereotyping and scapegoating demanded emotionally compelling interventions.
The researchers set out to create virtual worlds with characters that children could interact and empathize with powerfully enough to change their own attitudes and behavior.
The EU-funded research project eCIRCUS (Education through Characters with emotional-Intelligence and Role-playing Capabilities that Understand Social interaction) has now produced two programs – FearNot! and ORIENT – that give students helpful roles in interactive virtual worlds, where they can learn to change their thoughts, feelings and actions.
Finding new ways to resolve such problems is important, says eCIRCUS coordinator Ruth Aylett, because they are pervasive, hurtful, and can cause lasting psychological damage.
“Knowledge-based interventions don’t necessarily succeed,” says Aylett. “If we’re able to reduce victimization, we’re giving people a way to get out of a very painful situation and improve the quality of their lives.”
FearNot! – help for bullied children
The eCIRCUS researchers first focused on primary school children who were the victims of bullying. They drew on recent psychological theories that highlight the importance of feelings for changing how people treat each other.
“Emotion is an essential part of human interaction,” says Aylett, “so education about human social interaction must include feelings.”
The theories led them to expect that if they could get children to empathize with and try to help victims of bullying in a virtual world, the children could try out different strategies, experience the results, and develop better ways to deal with bullying in their own lives.
The researchers used a computer program, called FearNot! (Fun with Empathic Agents to Achieve Novel Outcomes in Teaching), that had been developed as an initial small prototype by an earlier European research effort called VICTEC.
The eCIRCUS team made FearNot! much richer in content and more open-ended. For example, they provided virtual bullying victims with the ability to remember strategies that they have tried. Those memories allow the virtual characters to reject approaches that have failed and ask the children who are helping them in the simulation to come up with better ideas.
“We are the first people to produce software for dealing with bullying that is not pre-scripted,” says Aylett. “We’ve produced something that is genuinely interactive to the individual responses of each child.”
ORIENT – empathizing with newcomers
While FearNot! has younger children interacting with cartoon-like characters in a simple world, ORIENT immerses older students in a much more vivid and complex virtual world, where they learn to empathize with and accept newcomers from other cultures.
In ORIENT, three students are equipped with various handheld control devices and “beamed down” as a team to save the planet Orient.
Planet Orient is populated by aliens called Sprytes, who look rather like large bipedal tree frogs and who have their own language and customs. Students have to learn a lot about the Sprytes and empathize with them in order to help them.
“We wanted users to feel adrift in this alien culture,” says Aylett. “How can you empathise with new people in your own culture if you’ve never experienced being adrift yourself?”
The software that shapes what happens as students interact with the Sprytes acts like the director of an improvisational drama. The software starts and ends scenes, chooses which characters appear, and can impose challenges such as a storm.
Each Spryte has its own goals, feelings and memories that control what it does and that can change based on experience. The interaction between the Sprytes and the students produces an unpredictable “emergent narrative”.
“There’s no fixed plot,” says Aylett. “Our characters are acting autonomously, making up their minds as they go.”
According to Aylett, students standing in front of a large screen and interacting with these psychologically believable aliens soon respond as if they were real. “ORIENT produces the feeling of really being there,” she says.