Week Ending FRIDAY July 17, 2009---------------------------News Archive / Return to News Alerts
Homing In On a Cause of Blue Baby Syndrome
M The most common form of blue baby syndrome, the serious congenital heart defect known as tetralogy of Fallot (TOF), has always been something of a puzzle for biomedical science. Seventy percent of the time, the condition, which causes a newborn's skin to turn blue from lack of oxygen in the blood, arises without any explanation.
Now, a team of researchers led by Howard Hughes Medical Institute investigator Christine Seidman of Brigham and Women's Hospital and Harvard University Medical School, has found genetic clues that narrow the search for the underlying cause of TOF. Many of the genetic culprits, they find, arise in patients without being passed on by the parents. The team’s results are reported online July 13, 2009, in the journal Nature Genetics.
“Copy number variations may help us to identify genes that cause other serious birth defects.”
Christine E. Seidman
"The study represents an important step forward in understanding the cause of tetralogy of Fallot," says Seidman, who led the study by an international group of researchers with her husband, HHMI alumni investigator Jonathan Seidman, also of Harvard Medical School. "Until now, the etiologies of TOF have been largely unknown."
Babies affected by TOF have malformed hearts that cannot fully oxygenate the blood. This causes cyanosis, a blue coloration of the skin due to deoxygenated hemoglobin in blood vessels near the skin surface. TOF can be treated surgically, but remains a serious, lifelong problem and frequently results in early mortality. It occurs in about one in 3,000 live births, and accounts for 10 percent of all serious congenital heart disease.
TOF is puzzling, Seidman says, because the parents of most babies with the condition have normal hearts and seem to confer no genetic predisposition for the defect. Some instances of TOF have been blamed on prenatal infection, maternal illness, or exposure to chemicals that interfere with an embryo’s development, but the majority of cases are unexplained.
Some cases of the condition have been linked to mutations in known heart-related genes, though those particular mutations do not consistently cause TOF. These hints at a genetic component, however, spurred Seidman and colleagues to scour the genomes of 114 TOF patients in search of more definitive answers. The group identified 11 segments of DNA that, in some patients, were present in too many or too few copies not the standard two copies found in individuals without TOF.
These kinds of genetic changes, known as copy number variations, alter the "dose" of a given gene -- changing how much of its protein is produced by a cell. Gains or losses of large chunks of DNA have been linked a number of disorders, and specific copy number variations are known to increase the risk of autism, schizophrenia, and certain cancers, and alter individuals’ susceptibility to HIV. But they can be hard to find.
"Until very recently, to a large extent, we didn’t know these things existed," Seidman says. However, newly available technology for detecting variations in genetic sequence a specialized gene chip -- has given researchers the ability to scan whole genomes and look for copy number variations.
The next step for Seidman's team was to determine whether these copy number variations were present in the genomes of other patients with TOF. They examined the DNA of another 398 patients, and concluded that seven of the copy number variations they had identified substantially increased the risk of TOF. One example is a gene called RAF1, which influences the growth, movement, and survival of cells. Excess copies of RAF increase the risk of TOF nine-fold. "Just changing the dose of that one gene causes tetralogy of Fallot," Seidman says.
Many of the copy number variations that the team detected were large, spanning multiple genes. Those regions of DNA, they say, should be prioritized for future study so that researchers can zero in on exactly which of their genes contribute to TOF.
Notably, Seidman’s team also analyzed the DNA of patients’ parents none of whom had TOF. The copy number variations they found in the patients’ DNA were, in almost all cases, not present in the parents’ DNA. As many as ten percent of the patients in their analysis had copy number variations that were not inherited from their parents. That, Seidman says, helps explain a diverse genetic underpinning for the serious heart malformation.
According to Seidman, the study shows that new molecular techniques can now be used to comb genomes in exquisite detail and identify very small differences in DNA that can have big effects. The strategy, she says, can be applied to other conditions and help identify the molecular underpinning of diseases whose causes are unknown. "Copy number variations can provide clues for studying other congenital malformations," says
Seidman. "That's the other take home message of the study. Copy number variations may help us to identify genes that cause other serious birth defects."
ONLINE: Save EXTRA $5 off $50 w/code SEARS50OFF50) at cart, 5/24/09 to 1/31/10
Eating High Levels of Fructose Impairs Memory in Rats
Researchers at Georgia State University have found that diets high in fructose a type of sugar found in most processed foods and beverages impaired the spatial memory of adult rats
Amy Ross, a graduate student in the lab of Marise Parent, associate professor at Georgia State’s Neuroscience Institute and Department of Psychology, fed a group of Sprague-Dawley rats a diet where fructose represented 60 percent of calories ingested during the day.
She placed the rats in a pool of water to test their ability to learn to find a submerged platform, which allowed them to get out of the water. She then returned them to the pool two days later with no platform present to see if the rats could remember to swim to the platform’s location.
“What we discovered is that the fructose diet doesn't affect their ability to learn,” Parent said. “But they can't seem to remember as well where the platform was when you take it away. They swam more randomly than rats fed a control diet.”
Fructose, unlike another sugar, glucose, is processed almost solely by the liver, and produces an excessive amount of triglycerides fat which gets into the bloodstream. Triglycerides can interfere with insulin signaling in the brain, which plays a major role in brain cell survival and plasticity, or the ability for the brain to change based on new experiences.
Results were similar in adolescent rats, but it is unclear whether the effects of high fructose consumption are permanent, she said.
Parent’s lab works with Timothy Bartness, Regents’ Professor of Biology, and John Mielke of the University of Waterloo in Waterloo, Ontario, Canada to examine how diet influences brain function.
Although humans do not eat fructose in levels as high as rats in the experiments, the consumption of foods sweetened with fructose which includes both common table sugar, fruit juice concentrates, as well as the much-maligned high fructose corn syrup has been increasing steadily. High intake of fructose is associated with numerous health problems, including insulin insensitivity, type II diabetes, obesity and cardiovascular disease.
“The bottom line is that we were meant to have an apple a day as our source of fructose,” Parent said. “And now, we have fructose in almost everything.” Moderation is key, as well as exercise, she said.
Exercise is a next step in ongoing research, and Parent’s team will investigate whether exercise might mitigate the memory effects of high fructose intake. Her lab is also researching whether the intake of fish oil can prevent the increase of triglycerides and memory deficits. Results from that research will be presented by her graduate student Emily Bruggeman at the 2009 Society for Neuroscience meeting in Chicago this fall.
Male Sex Chromosome Losing Genes
Scientists have long suspected that the sex chromosome that only males carry is deteriorating and could disappear entirely within a few million years, but until now, no one has understood the evolutionary processes that control this chromosome's demise
Now, a pair of Penn State scientists has discovered that this sex chromosome, the Y chromosome, has evolved at a much more rapid pace than its partner chromosome, the X chromosome, which both males and females carry. This rapid evolution of the Y chromosome has led to a dramatic loss of genes on the Y chromosome at a rate that, if maintained, eventually could lead to the Y chromosome's complete disappearance. The research team, which includes Associate Professor of Biology Kateryna Makova, the team's leader, and National Science Foundation Graduate Research Fellow Melissa Wilson, will publish its results in the 17 July 2009 issue of the journal PLoS Genetics.
"There are three classes of mammals," said Makova, "egg-laying mammals, like the platypus and the echidna; marsupials, like the opossum and the wallaby; and all other mammals - called eutherians - which include humans, dogs, mice, and giraffes. The X and Y chromosomes of marsupials and eutherians evolved from a pair of non-sex chromosomes to become sex chromosomes."
Humans have 23 pairs of chromosomes, which are the structures that hold our DNA, but just one pair of these chromosomes are sex chromosomes, while the others are referred to as non-sex chromosomes. "In eutherian mammals, the sex chromosomes contain an additional region of DNA whereas, in the egg-laying mammals and marsupials, this additional region of DNA is located on the non-sex chromosomes," said Makova. "At first, bits of DNA within this additional region were readily swapped between the X and Y chromosomes, but some time between 80 and 130 million years ago, the region became two completely separate entities that no longer swapped DNA. One of the regions became specifically associated with the X chromosome and the other became specifically associated with the Y chromosome."
By comparing the DNA of the X and Y chromosomes in eutherian mammals to the DNA of the non-sex chromosomes in the opossum and platypus, the team was able to go back in time to the point when the X and Y chromosomes were still swapping DNA, just like the non-sex chromosomes in the opossum and platypus. The scientists then were able to observe how the DNA of the X and Y chromosomes changed over time relative to the DNA of the non-sex chromosomes. "Our research revealed that the Y-specific DNA began to evolve rapidly at the time that the DNA region split into two entities, while the X-specific DNA maintained the same evolutionary rate as the non-sex chromosomes," said Makova.
Once the biologists determined that the Y chromosome has been evolving more rapidly and has been losing more genes as a result, they wanted to find out why the Y chromosome has not already disappeared entirely. "Today, the human Y chromosome contains less than 200 genes, while the human X chromosome contains around 1,100 genes," said Wilson. "We know that a few of the genes on the Y chromosome are important, such as the ones involved in the formation of sperm, but we also know that most of the genes were not important for survival because they were lost, which led to the very different numbers of genes we observe between the once-identical X and Y. Although there is evidence that the Y chromosome is still degrading, some of the surviving genes on the Y chromosome may be essential, which can be inferred because these genes have been maintained for so long."
The team then decided to test the hypothesis that some of the genes on the Y chromosome are being maintained because they are essential. The team's approach was to compare the expression and function of genes on the Y chromosome with analogous genes on the X chromosome. "If the genes' expressions and/or functions were different, then it would make sense that the genes on the Y chromosome would be maintained because they are doing something that the genes on the X chromosome can't do," said Makova. "This hypothesis turned out to be correct."
Although some of the genes on the Y chromosome have been maintained, most of them have died, and the team found evidence that some others are on track to disappear, as well. "Even though some of the genes appear to be important, we still think there is a chance that the Y chromosome eventually could disappear," said Makova. "If this happens, it won't be the end of males. Instead, a new pair of non-sex chromosomes likely will start on the path to becoming sex chromosomes."
In the future, the team plans to use its newly generated data to create a computer model that tracks the degeneration of the Y chromosome. The scientists hope to determine how long it will take for the Y chromosome to disappear. They also hope to identify the processes that are most important for degeneration of the Y chromosome.
Save $5 off $50 with coupon code KMART5OFF50 at Kmart.com, no expiration
Why Winning Athletes Are Getting Bigger
While watching swimmers line up during the 2008 Olympic Games in Beijing, former Olympic swimmer and NBC Sports commentator Rowdy Gaines quipped that swimmers keep getting bigger, with the shortest one in the current race towering over the average spectator
What may have been seen as an off-hand remark turns out to illustrate a trend in human development -- elite athletes are getting bigger and bigger.
What Gaines did not know was that a new theory by Duke University engineers has indeed showed that not only have Olympic swimmers and sprinters gotten bigger and faster over the past 100 years, but they have grown at a much faster rate than the normal population.
Futhermore, the researchers said, this pattern of growth can be predicted by the constructal theory, a Duke-inspired theory of design in nature that explains such diverse phenomena as river basin formation and the capillary structure of tree branches and roots. (www.constructal.com).
In a new analysis, Jordan Charles, an engineering student who graduated this spring, collected the heights and weights of the fastest swimmers (100 meters) and sprinters (100 meters) for world record winners since 1900. He then correlated the size growth of these athletes with their winning times.
"The trends revealed by our analysis suggest that speed records will continue to be dominated by heavier and taller athletes," said Charles, who worked with senior author Adrian Bejan, engineering professor who came up with the constructal theory 13 years ago. The results of their analysis were published online in the Journal of Experimental Biology. "We believe that this is due to the constructal rules of animal locomotion and not the contemporary increase in the average size of humans."
Specifically, while the average human has gained about 1.9 inches in height since 1900, Charles' research showed that the fastest swimmers have grown 4.5 inches and the swiftest runners have grown 6.4 inches.
The theoretical rules of animal locomotion generally state that larger animals should move faster than smaller animals. In his contructal theory, Bejan linked all three forms of animal locomotion -- running, swimming and flying. Bejan argues that the three forms of locomotion involve two basic forces: lifting weight vertically and overcoming drag horizontally. Therefore, they can be described by the same mathematical formulas. (http://www.pratt.duke.edu/news/?id=1692)
Using these insights, the researchers can predict running speeds during the Greek or Roman empires, for example. In those days, obviously, time was not kept.
"In antiquity, body weights were roughly 70 percent less than they are today," Charles said. "Using our theory, a 100-meter dash that is won in 13 seconds would have taken about 14 seconds back then."
Charles, a varsity breaststroke swimmer during his time at Duke, said this new way of looking at locomotion and size validates a particular practice in swim training, though for a different reason. Swimmers are urged by their coaches to raise their body as far as they can out of the water with each stroke as a means of increasing their speed.
"It was thought that the swimmer would experience less friction drag in the air than in the water," Charles said. "However, when the body is higher above the water, it falls faster and more forward when it hits the water. The larger wave that occurs is faster and propels the body forward. A larger swimmer would get a heightened effect. Right advice, wrong reason."
In an almost whimsical corollary, the authors suggest that if athletes of all sizes are to compete in these kinds of events, weight classes might be needed.
"In the future, the fastest athletes can be predicted to be heavier and taller," Bejan said. "If the winners' podium is to include athletes of all sizes, then speed competitions might have to be divided into weight categories. Larger athletes lift, push and punch harder than smaller athletes, and this led to the establishment of weight classes in certain sports, like boxing, wrestling or weight-lifting.
THURSDAY July 16, 2009---------------------------News Archive / Return to News Alerts
Ask Permission to Use Newborn Data, Parents Say
More than three-quarters of parents would be willing to permit the use of their children’s newborn screening samples for research purposes if their permission were obtained beforehand, a University of Michigan survey shows.
But permission is crucial: More than half of the parents surveyed said they would be “very unwilling” to permit use of their child’s newborn screening sample for future research unless they were allowed a chance to grant or deny permission.
This national survey was conducted as part of the CS Mott Children’s Hospital National Poll on Children’s Health to shed light on the emerging issue of how to square parents’ concerns about privacy with medical researchers’ desire to use the amazing array of health data available in newborn blood samples. These are routinely collected from infants in all 50 states at birth via a tiny needle-prick in the heel.
These state-required samples, taken to alert doctors to rare, serious inherited diseases that can be corrected if treated early, are stored by health agencies for years. Most parents are unaware the samples still exist, unless a sample proves useful for identification or to shed light on a child’s health condition. Realizing the samples’ collective value, researchers are beginning to use them to study the origins of childhood leukemia and toxin exposures in utero, and see potential for other beneficial research as well.
“Prior to this study, there was some debate about whether or not parents supported the idea of using the data for research, and whether they wanted their permission to be asked. We did the study to inform policy makers and others involved in the issue,” says Beth A. Tarini, M.D., M.S., assistant professor of pediatrics at the University of Michigan Medical School.
“Clearly, most parents want to be involved in this process,” says Tarini, who is a researcher at the Child Health Evaluation and Research (CHEAR) Unit in the U-M Division of General Pediatrics. “Asking parents’ permission to use their children’s blood samples for future research looks like a critical issue.” The survey results appear online the journal Public Health Genomics. The survey was conducted using an Internet-based survey of a nationally representative sample of parents.
Researchers see the large existing database of newborn screening records as a rich resource for exploring a variety of diseases, but privacy advocates have raised concerns that have led to a lengthy legislative and court battle in Minnesota over whether the state’s newborn screening program violates privacy by storing and making samples available to researchers without formal consent from parents. In Texas, a group sued the state earlier this year, arguing that storage of the samples without obtaining informed consent is unconstitutional.
Parents in most states are not asked to give informed consent for storing or allowing use of the samples for research when private health information has been removed from the samples. Several states, most notably Michigan, are now evaluating more comprehensive policies for how the data are stored and used. The Michigan BioTrust for Health, established by the Michigan Department of Community Health, is seeking input from state residents on how best to store samples and under what conditions they should be studied.
Public policy that would allow use of newborn screening bloodspots for anonymized or de-identified research purposes without obtaining some form of permission from parents does not appear to be palatable to the public, says Tarini.
“If policy makers fail to engage in a discussion with parents and the public about using the screening results for research, that could create a public backlash and threaten the viability of a potentially valuable public health resource.”
ONLINE: Save EXTRA $5 off $50 w/code SEARS50OFF50) at cart, 5/24/09 to 1/31/10
Brain Emotion Circuit Sparks as Teen Girls Size Up Peers
What is going on in teenagers' brains as their drive for peer approval begins to eclipse their family affiliations?
Brain scans of teens sizing each other up reveal an emotion circuit activating more in girls as they grow older, but not in boys. The study by Daniel Pine, M.D., of the National Institute of Mental Health (NIMH), part of National Institutes of Health, and colleagues, shows how emotion circuitry diverges in the male and female brain during a developmental stage in which girls are at increased risk for developing mood and anxiety disorders.
"During this time of heightened sensitivity to interpersonal stress and peers' perceptions, girls are becoming increasingly preoccupied with how individual peers view them, while boys tend to become more focused on their status within group pecking orders," explained Pine. "However, in the study, the prospect of interacting with peers activated brain circuitry involved in approaching others, rather than circuitry responsible for withdrawal and fear, which is associated with anxiety and depression."
Pine, Amanda Guyer, Ph.D., Eric Nelson, Ph.D., and colleagues at NIMH and Georgia State University, report on one of the first studies to reveal the workings of the teen brain in a simulated real-world social interaction, in the July, 2009 issue of the Journal Child Development.
Thirty-four psychiatrically healthy males and females, aged 9 to 17, were ostensibly participating in a study of teenagers' communications via Internet chat rooms. They were told that after an fMRI (functional magnetic resonance imaging) scan, which visualizes brain activity, they would chat online with another teen from a collaborating study site. Each participant was asked to rate his or her interest in communicating with each of 40 teens presented on a computer screen, so they could be matched with a high interest participant (see picture below).
Two weeks later, the teens viewed the same faces while in an fMRI scanner. But this time they were asked to instead rate how interested they surmised each of the other prospective chatters would be in interacting with them.
Only after they exited the scanner did they learn that, in fact, the faces were of actors, not study participants, and that there would be no Internet chat. The scenario was intended to keep the teens engaged maintain a high level of anticipation/motivation during the tasks. This helped to ensure that the scanner would detect contrasts in brain circuit responses to high interest versus low interest peers.
Although the faces were selected by the researchers for their happy expressions, their attractiveness was random, so that they appeared to be a mix of typical peers encountered by teens.
As expected, the teen participants deemed the same faces they initially chose as high interest to be the peers most interested in interacting with them. Older participants tended to choose more faces of the opposite sex than younger ones. When they appraised anticipated interest from peers of high interest compared with low interest, older females showed more brain activity than younger females in circuitry that processes social emotion.
"This developmental shift suggested a change in socio-emotional calculus from avoidance to approach," noted Pine. The circuit is made up of the nucleus accumbens (reward and motivation), hypothalamus (hormonal activation), hippocampus (social memory) and insula (visceral/subjective feelings).
By contrast, males showed little change in the activity of most of these circuit areas with age, except for a decrease in activation of the insula. This may reflect a waning of interpersonal emotional ties over time in teenage males, as they shift their interest to groups, suggest Pine and colleagues.
"In females, absence of activation in areas associated with mood and anxiety disorders, such as the amygdala, suggests that emotional responses to peers may be driven more by a brain network related to approach than to one related to fear and withdrawal," said Pine. "This reflects resilience to psychosocial stress among healthy female adolescents during this vulnerable period."
For the first time, the Society of Interventional Radiology has assembled a major electronic collection of professional articles about uterine artery embolization, a treatment directed toward a number of conditions involving the uterusmost often adverse health effects that may occur due to the presence of uterine fibroids
The Journal of Vascular and Interventional Radiology "virtual" collection allows health care providers and the public to view the abstracts on current research on this topic in one place, eliminating the need to search topics individually.
Uterine fibroids are very common noncancerous growths that develop in the muscular wall of the uterus. Hysterectomy, surgical removal of the uterus performed by a gynecologist, is the most common treatment for symptomatic uterine fibroids. In fact, more than 200,000 women in the United States have hysterectomies for fibroids each year; it is the second most common surgery among women. However, most women are candidates for uterine artery embolization (also called uterine fibroid embolization).
"Uterine artery embolization is a treatment method for fibroids that is relatively noninvasive and has high success rates. Women with fibroids and their health care providers should be aware of this therapy. This collection assembles relevant information about the interventional radiology treatment in one convenient place," explained Albert A. Nemcek Jr., M.D., FSIR, editor of JVIR, a peer-reviewed, monthly publication long recognized for its exceptional quality and influence as an academic and professional resource.
"The value for physicians and patients is the convenience of having all the recent articles from a major journal in one place. While it is not a comprehensive list of all recent uterine artery embolization articles, many of the major studies are included, particularly those that relate to the technical aspects of the procedure," said James B. Spies, M.D., FSIR, JVIR section editor for women's health.
"Nearly all the new innovations in the procedure have been reported in JVIR first. The collection has particular value to physicians who are just entering the field or who are in training, as it provides a continuum of the recent innovations in the procedure and is a good example of how medical research progresses over time," added Spies, professor of radiology and chair of the Department of Radiology at Georgetown University Medical Center in Washington, D.C.
Uterine artery embolization, a minimally invasive, targeted treatment, offers less risk, less pain and less recovery time than traditional surgery. Interventional radiologists use expertise in imaging to deliver treatment directly to a fibroid, blocking the flow of blood to the tumor and causing it to shrink.
"With these modern treatments, hopefully the trend to offer traditional surgery first will be reversed. It's important for patients to ask questions, obtain consults with different types of doctors and know all their treatment options," added Nemcek, an interventional radiologist and professor of radiology and surgery at Northwestern Memorial Hospital in Chicago, Ill.
The 46-article collection of previously published articles and abstractswith some of the leading researchers in the fieldis divided into nine sections: indications, uterine imaging, technique, outcomes, other indications for embolization, economics, radiation exposure, other procedures and animal studies.
According to Spies, the collection includes an important article, "Leiomyoma Infarction After Uterine Artery Embolization: A Prospective Randomized Study Comparing Tris-acryl Gelatin Microspheres Versus Polyvinyl Alcohol Microspheres," a randomized study by Gary P. Siskin, M.D., FSIR, and colleagues at Albany Medical College, that answers a key technical question regarding choice of embolic material.
Also important are "Economic Evaluation of Uterine Artery Embolization Versus Hysterectomy in the Treatment of Symptomatic Uterine Fibroids: Results From the Randomized EMMY Trial" and "Payer Costs in Patients Undergoing Uterine Artery Embolization, Hysterectomy or Myomectomy for Treatment of Uterine Fibroids." These latter two articles provide strong evidenceobtained in two different waysthat uterine artery embolization is less costly than traditional surgery, said Spies.
Save $5 off $50 with coupon code KMART5OFF50 at Kmart.com, no expiration
Rejection for $500, Please: Money and Its Symbolic Powers
When we are feeling blue we are told to count our blessings, but according to a study recently published in Psychological Science, counting our money might be a more useful activity
Psychologists Xinyue Zhou, Sun Yat-Sen University, Kathleen D. Vohs, University of Minnesota, and Roy F. Baumeister, Florida State University, investigated the psychological, physical and social impact of money.
To examine this, the researchers asked one group of participants to count out eighty $100 bills and another group to count eighty worthless pieces of paper. They then played a computerized ball-tossing game called Cyperball.
The participants were led to believe that they were playing with three other gamers when the other players in fact were computer generated. Some participants received the ball an equal amount of times while other participants were excluded. Out of the participants excluded in the Cyperball game, those who had counted the money rated lower social distress than those who only counted paper.
In another experiment, the scientists asked participants to immerse their fingers in hot water for 30 seconds after they counted either money or paper. Surprisingly, those counting money rated a lower intensity of the hot water and physical pain than those who counted paper. In addition, the researchers found that participants who counted out the bills rated themselves as feeling "strong" more often than the paper counting group.
Adding a twist to the experiment, the scientists asked a group of participants to list their monetary expenditures from the past month and another group to list weather conditions in the past month.
Both groups were then put through the Cyperball game and the physical pain test. Those who thought about the weather rated normal amounts of social distress or pain; those thinking about their finances experienced higher social distress when they were left out of the Cyperball game and reported greater pain from the hot water.
As the psychologists concluded, "The mere idea of money has considerable psychological power, enough to alter reactions to social exclusion and even to physical pain."
WEDNESDAY July 15, 2009---------------------------News Archive / Return to News Alerts
In Love? It's Not Enough to Keep a Marriage, Study Finds
Living happily ever after needn't only be for fairy tales. Australian researchers have identified what it takes to keep a couple together, and it's a lot more than just being in love
A couple's age, previous relationships and even whether they smoke or not are factors that influence whether their marriage is going to last, according to a study by researchers from the Australian National University.
The study, entitled "What's Love Got to Do With It", tracked nearly 2,500 couples -- married or living together -- from 2001 to 2007 to identify factors associated with those who remained together compared with those who divorced or separated.
It found that a husband who is nine or more years older than his wife is twice as likely to get divorced, as are husbands who get married before they turn 25.
Children also influence the longevity of a marriage or relationship, with one-fifth of couples who have kids before marriage -- either from a previous relationship or in the same relationship -- having separated compared to just nine percent of couples without children born before marriage.
Women who want children much more than their partners are also more likely to get a divorce.
A couple's parents also have a role to play in their own relationship, with the study showing some 16 percent of men and women whose parents ever separated or divorced experienced marital separation themselves compared to 10 percent for those whose parents did not separate.
Also, partners who are on their second or third marriage are 90 percent more likely to separate than spouses who are both in their first marriage.
Not surprisingly, money also plays a role, with up to 16 percent of respondents who indicated they were poor or where the husband -- not the wife -- was unemployed saying they had separated, compared with only nine percent of couples with healthy finances.
And couples where one partner, and not the other, smokes are also more likely to have a relationship that ends in failure.
Factors found to not significantly affect separation risk included the number and age of children born to a married couple, the wife's employment status and the number of years the couple had been employed.
The study was jointly written by Dr Rebecca Kippen and Professor Bruce Chapman from The Australian National University, and Dr Peng Yu from the Department of Families, Housing, Community Services and Indigenous Affairs.
ONLINE: Save EXTRA $5 off $50 w/code SEARS50OFF50) at cart, 5/24/09 to 1/31/10
Study Explains Potential Failure of Oral Contraceptives With Obese Women
Researchers have identified a potential biological mechanism that could explain why oral contraceptives may be less effective at preventing pregnancy in obese women, as some epidemiological studies have indicated
Although conventional oral contraceptives appear to eventually reach the effective blood concentrations needed in the body to prevent conception in obese women, it appears to take twice as long, leaving a "window of opportunity" every month where the contraceptive may not be at a high enough level to prevent a pregnancy.
The findings are of particular importance, researchers noted in their study, because about 30 percent of all adults in the U.S. are obese and the birth control pill is one of the most popular forms of contraception in the nation.
"We don't have enough data yet to recommend that physicians change their clinical practice for use of oral contraceptives with patients who are very overweight," said Ganesh Cherala, an assistant professor in the College of Pharmacy at Oregon State University. "However, until more studies are done, women may wish to consult with their physicians about this issue and consider a backup method of contraception at some times of the month."
The study was just published in the journal Contraception, by scientists from OSU, Oregon Health and Science University, University of Colorado at Denver, Oregon National Primate Research Center, and the University of Southern California. The research was supported by the National Institutes of Health.
The underlying problem, Cherala said, is that oral contraceptives, like most drugs, are initially tested in "healthy" people, which rarely includes people who are more than 130 percent of their ideal body weight.
"When we first test drugs for safety and efficacy, we generally do not include people with a high body mass index," Cherala said. "But body weight and amounts of fat can seriously change the pharmacokinetics, or way drugs act and are processed in the body. There's a growing awareness that we need to more carefully consider obesity and other factors that affect drug absorption, distribution, metabolism and other factors."
Conventional oral contraceptives, Cherala said, are thought to be relatively "lipophilic," or tend to concentrate in fat tissue. However, the researchers in this study said they were somewhat surprised to find that the affinity of these drugs for fat tissue was not significantly different between obese and normal body weight subjects.
Rather, the researchers found that contraceptive drug levels in both obese women and those of normal weight eventually were about the same, but it took longer to achieve that level in very overweight women.
The study showed it took an average of about five days for the drugs to achieve their maximum concentration in women of normal weight, an average of 10 days for obese women, and even longer than that for some individuals. One woman in the study took more than 20 days to reach a "steady state" drug concentration. Women of normal weight who follow their oral contraceptive directions should have appropriate protection against pregnancy. But the delay in reaching a steady state drug concentration raises questions about how well oral contraceptives may work for obese women.
Increasing the drug dosage might help address this issue, Cherala said, but also adds other health concerns.
In fact, the researchers noted in their report that many clinicians actually prescribe lower-dose oral contraceptives to obese patients in an effort to decrease their risk of venous thrombosis. These are blood clots in the legs or elsewhere that can increase the risk of stroke and heart attacks.
The study was done with 20 women of ages 18 to 35, all of them healthy and seeking contraception, 10 of whom were of normal weight and 10 with a "body mass index" of more than 30 a common measure of obesity.
According to Dr. Alison Edelman, lead author of the study and assistant director of the Family Planning Fellowship at Oregon Health and Science University, the participants in this study were purposely selected for obesity in order to explore this issue. But several demographic studies have shown that even women just considered "overweight," with a body mass index of 25-30, may also be at increased risk of contraceptive failure.
"Although our research has found this interaction between obese women and oral contraceptives, we don't have enough information yet to recommend changes in clinical practice, other than choosing a contraceptive option that works better for both normal weight and obese women, like an intrauterine device," Edelman said.
For future work, she said, studies of contraception would be more useful if they included participants that reflect the general population, including women with different body mass indexes. The biological underpinnings of how oral contraceptives work, their effects on the hypothalamic-pituitary-ovarian axis, has only been studied in women of normal weight, the researchers noted in their study.
At present, Cherala said, there is no readily available test that would tell a woman how long it would take for her to reach an effective concentration level of a particular contraceptive, and this does vary with the individual. However, scientists are continuing research on that issue, and they may ultimately develop tests or methods that would improve drug efficacy for women who wish to use oral contraceptives.
Early-Life Experience Linked to Chronic Diseases Later in Life
People’s early-life experience sticks with them into adulthood and may render them more susceptible to many of the chronic diseases of aging, according to a new UBC study.
A team led by UBC researchers Gregory Miller and Michael Kobor performed genome-wide profiling in 103 healthy adults aged 25-40 years.
Those who participated in the study were either low or high in early-life socioeconomic circumstances related to income, education and occupation during the first five years of life. But the two groups were similar in socioeconomic status (SES) at the time the genome assessment was performed and also had similar lifestyle practices like smoking and drinking habits.
Their study, to be published in this week’s Proceedings of the National Academy of Sciences, shows that among subjects with low early-life socioeconomic circumstances, there was evidence that genes involved with inflammation were selectively “switched-on” at some point. Researchers believe this is because the cells of low-SES individuals were not effectively responding to a hormone called cortisol that usually controls inflammation.
“We’ve identified some ‘biologic residue’ of people’s early-life experience that sticks with them into adulthood,” says Miller, an associate professor in the Department of Psychology and a member of the Brain Research Centre at UBC Hospital.
“The study suggests that experiences get under the skin,” says Kobor, an assistant professor in the UBC Department of Medical Genetics and a scientist at the Centre for Molecular Medicine and Therapeutics at the Child & Family Research Institute.
This pattern of responses might contribute to the higher rates of infectious, respiratory, and cardiovascular diseases as well as some forms of cancer among people who grow up in low-SES households, according to the interdisciplinary research team that also includes scientists from the University of California, Los Angeles.
“It seems to be the case that if people are raised in a low socioeconomic family, their immune cells are constantly vigilant for threats from the environment,” says Miller. “This is likely to have consequences for their risk for late-life chronic diseases.”
Save $5 off $50 with coupon code KMART5OFF50 at Kmart.com, no expiration
New Technique Could Sustain Cancer Patients' Fertility
Researchers grow immature egg cells in the laboratory for 30 days
Researchers funded by the National Institutes of Health have completed a critical first step in the eventual development of a technique to retain fertility in women with cancer who require treatments that might otherwise make them unable to have children.
The researchers have developed a method to advance undeveloped human eggs to near maturity, in laboratory cultures maintained outside the body. The technique focuses on the follicle, a tiny sac within the ovary that contains the immature egg. The researchers were able to grow human follicles in the laboratory for 30 days, until the eggs they contained were nearly mature.
The research seeks to provide women who require a fertility-ending treatment with options for reproduction after their treatment is complete. Men facing such treatments can freeze their sperm for use at a later date. Female cancer patients have fewer options. Unlike sperm, eggs rarely survive freezing and thawing.
The accomplishment represents the successful completion of the first of three steps needed to preserve a woman's fertility after radiation treatments or chemotherapy. For the next step, researchers will need to induce the egg's final division, so that it contains only half the genetic material of its precursors. Finally, the researchers will have to demonstrate that they can freeze and thaw human follicles before growing them in culture.
"The new technique could provide an option for women and girls who have cancer and are not yet ready to start families," said Duane Alexander, M.D., director of NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), which funded the research as part of the NIH Roadmap Interdisciplinary Research Consortium program. "An additional benefit is that it will allow researchers to more closely follow the process by which immature eggs grow and mature. In turn, these observations may lead to new advances for treating other forms of infertility."
The best option currently for a female cancer patient to preserve fertility is to collect eggs, fertilize them with sperm, and freeze the resulting embryos. But that technique may not be acceptable to all female cancer patients.
Researchers have already identified experimental methods to freeze entire ovaries or strips of ovarian tissue and implant them in a woman's body when she is ready to have children. This is a good option for some patients, but it is possible that some cancer cells may hitch hike on the ovarian tissue and result in a new cancer after treatment is completed.
Developed by Teresa K. Woodruff, Ph.D. and Lonnie D. Shea, Ph.D., of Northwestern University's Feinberg School of Medicine, and their colleagues, the new technique would avoid both concerns.
The findings were published online in Human Reproduction.
The new findings build on earlier efforts by the research team, who grew mouse follicles in culture, induced the eggs they contained to mature, fertilized them with mouse sperm, and implanted them into female mice to establish pregnancy. The earlier research is described in an article that appeared in The NIH Record, at http://nihrecord.od.nih.gov/newsletters/2006/09_08_2006/story02.htm.
The researchers made the new advance by suspending the human follicle in a three-dimensional matrix of a gel-like material. They then flushed the follicle with the same hormones and growth factors that the follicle would be exposed to inside a woman's body.
In previous attempts to grow follicles, researchers had set the follicles on a flat surface, which the study authors now believe does not mimic closely enough conditions inside the body. These earlier attempts failed to develop good quality eggs that were healthy enough for fertilization.
For the current study, the researchers started with so-called secondary follicles, which are at an intermediate stage of development. They collected them from the ovarian tissue of 14 cancer patients.
During the 30-day experiment, the follicle grew and produced hormones and the immature egg matured just as it would inside a woman's body. The researchers found that the follicles would grow if injected into a gelatin mixture. The gelatin (called alginate) provided three-dimensional support for the follicle, much like the support it receives inside the body.
"The researchers have demonstrated that the technique produces healthy eggs," said Charisee Lamar, Ph.D., M.P.H., R.R.T., director of the Fertility Preservation Program in NICHD's Reproductive Sciences Branch. "The next step would be to investigate the viability of follicles from frozen tissue."
Another component of the NICHD program is attempting to grow follicles of monkeys in culture. The ability to do research on mouse and monkey follicles might lead to advances that could later be used to perfect the technique's use with human eggs.
TUESDAY July 14, 2009---------------------------News Archive / Return to News Alerts
Hush Little Baby - Linking Genes, Brain, & Behavior in Children
It comes as no surprise that some babies are more difficult to soothe than others but frustrated parents may be relieved to know that this is not necessarily an indication of their parenting skills
According to a new report in Psychological Science, a journal of the Association for Psychological Science, children's temperament may be due in part to a combination of a certain gene and a specific pattern of brain activity.
The pattern of brain activity in the frontal cortex of the brain has been associated with various types of temperament in children. For example, infants who have more activity in the left frontal cortex are characterized as temperamentally "easy" and are easily calmed down. Conversely, infants with greater activity in the right half of the frontal cortex are temperamentally "negative" and are easily distressed and more difficult to soothe.
In this study, Louis Schmidt from McMaster University and his colleagues investigated the interaction between brain activity and the DRD4 gene to see if it predicted children's temperament.
In a number of previous studies, the longer version (or allele) of this gene had been linked to increased sensory responsiveness, risk-seeking behavior, and attention problems in children. In the present study, brain activity was measured in 9-month-old infants via electroencephalography (EEG) recordings. When the children were 48 months old, their mothers completed questionnaires regarding their behavior and DNA samples were taken from the children for analysis of the DRD4 gene.
The results reveal interesting relations among brain activity, behavior, and the DRD4 gene.
Among children who exhibited more activity in the left frontal cortex at 9 months, those who had the long version of the DRD4 gene were more soothable at 48 months than those who possessed the shorter version of the gene. However, the children with the long version of the DRD4 gene who had more activity in the right frontal cortex were the least soothable and exhibited more attention problems compared to the other children.
These findings indicate that the long version of the DRD4 gene may act as a moderator of children's temperament. The authors note that the "results suggest that it is possible that the DRD4 long allele plays different roles (for better and for worse) in child temperament" depending on internal conditions (the environment inside their bodies) and conclude that the pattern of brain activity (that is, greater activation in left or right frontal cortex) may influence whether this gene is a protective factor or a risk factor for soothability and attention problems.
The authors cautioned that there are likely other factors that interact with these two measures in predicting children's temperament.
ONLINE: Save EXTRA $5 off $50 w/code SEARS50OFF50) at cart, 5/24/09 to 1/31/10
Swearing Can Make You Feel Better
New research reveals that swearing can actually increase pain tolerance (and possibly make labor more tolerable?)
Researchers from Keele University’s School of Psychology have determined that swearing can have a ‘pain-lessening effect’, according to new study published in the journal NeuroReport.
While swearing is often a common response to pain, Dr Richard Stephens and his colleagues, John Atkins and Andrew Kingston, were surprised to discover that no links had been established between swearing and the actual experience of physical pain.
Since swearing often has a ‘catastrophising’ or exaggerating effect, serving to embellish or overstate the severity of pain, Stephens and his team hypothesised that swearing would actually decrease the individual’s tolerance of pain.
The Ice Water Test
Enlisting the help of 64 undergraduate volunteers, the team set out to test their theory. Each individual was asked to submerge their hand in a tub of ice water for as long as possible while repeating a swear word of their choice; they were then asked to repeat the experiment, this time using a more commonplace word that they would use to describe a table.
Despite their initial expectations, the researchers found that the volunteers were able to keep their hands submerged in the ice water for a longer period of time when repeating the swear word, establishing a link between swearing and an increase in pain tolerance.
While it isn’t clear how or why this link exists, the team believes that the pain-lessening effect occurs because swearing triggers our natural ‘fight-or-flight’ response.
They suggest that the accelerated heart rates of the volunteers repeating the swear word may indicate an increase in aggression, in a classic fight-or-flight response of ‘downplaying feebleness in favour of a more pain-tolerant machismo.’
What is clear is that swearing triggers not only an emotional response, but a physical one too, which may explain why the centuries-old practice of cursing developed and still persists today.
Dr Richard Stephens said: “Swearing has been around for centuries and is an almost universal human linguistic phenomenon. It taps into emotional brain centres and appears to arise in the right brain, whereas most language production occurs in the left cerebral hemisphere of the brain. Our research shows one potential reason why swearing developed and why it persists.”
The Morning-After Pill? How Does It Work?
The morning-after pill a form of emergency birth control is used to prevent a woman from becoming pregnant after she has had unprotected sex
Morning-after pills are generally considered safe, but many women are unaware that they exist.
Here's how the morning-after pill works. Human conception rarely occurs immediately after intercourse. Instead, it occurs as long as several days later, after ovulation. During the time between intercourse and conception, sperm continue to travel through the fallopian tube until the egg appears. So taking emergency birth control the "morning after" isn't too late to prevent pregnancy.
The active ingredients in morning-after pills are similar to those in birth control pills, except in higher doses. Some morning-after pills contain only one hormone, levonorgestrel (Plan B), and others contain two, progestin and estrogen. Progestin prevents the sperm from reaching the egg and keeps a fertilized egg from attaching to the wall of the uterus (implantation). Estrogen stops the ovaries from releasing eggs (ovulation) that can be fertilized by sperm.
The morning-after pill is designed to be taken within 72 hours of intercourse with a second dose taken 12 hours later. Side effects may include nausea, vomiting, abdominal pain, fatigue, dizziness, menstrual changes and headache. According to the manufacturer, the morning-after pill is more than 80 percent effective in preventing pregnancy after a single act of unprotected sex.
Morning-after pills aren't the same as mifepristone (Mifeprex), the so-called abortion pill. Emergency contraceptive pills such as Plan B prevent pregnancy. The abortion pill terminates an established pregnancy one in which the fertilized egg has attached to the uterine wall and has already begun to develop.
Plan B is available to women and girls age 17 and older without a prescription at most pharmacies. You must show proof of age to purchase Plan B. For girls age 16 and younger, Plan B is available only with a doctor's prescription.
Save $5 off $50 with coupon code KMART5OFF50 at Kmart.com, no expiration
Largest in Children, The Thymus Gland May Control Aging
The secret to longevity may lie in an enzyme with the ability to promote a robust immune system into old age by maintaining the function of the thymus throughout life, according to researchers studying an "anti-aging" mouse model that lives longer than a typical mouse.
The study, led by Abbe de Vallejo, Ph.D., associate professor of pediatrics and immunology, University of Pittsburgh School of Medicine, and immunologist at Children's Hospital of Pittsburgh of UPMC, reports that the novel mouse model has a thymus that remains intact throughout its life. In all mammals, the thymus―the organ that produces T cells to fight disease and infection―degenerates with age. Results of the study are published in this week's issue of the Proceedings of the National Academy of Sciences.
The thymus is of a pinkish-gray color, soft, and lobulated on its surfaces.
At birth it is about 5 cm in length, 4 cm in breadth, and about 6 mm in thickness. The organ enlarges during childhood, and atrophies at puberty.
Unlike the liver, kidney and heart, for instance, the thymus is at its largest in children.
The thymus reaches maximum weight (20 to 37 grams) by the time of puberty. It remains active only until puberty. Then with growing age, it starts to shrink.
"These findings give us hope that we may one day have the ability to restore the function of the thymus in old age, or perhaps by intervening at an early age, we may be able to delay or even prevent the degeneration of the thymus in order to maintain our immune defenses throughout life," said Dr. de Vallejo.
The mouse model that Dr. de Vallejo's team studied was developed by his colleague Cheryl Conover, Ph.D., an endocrinology researcher at Mayo Clinic. In this "knockout" mouse model, researchers deleted an enzyme known as pregnancy-associated plasma protein A (PAPPA). PAPPA-knockout mice live at least 30 percent longer and have significantly lower occurrence of spontaneous tumors than typical mice.
PAPPA controls the availability in tissues of a hormone known as insulin-like growth factor (IGF) that is a promoter of cell division. Hence, IGF is required for normal embryonic and postnatal growth. But IGF also is associated with tumor growth, inflammation and cardiovascular disease in adults. By deleting PAPPA, the researchers were able to control the availability of IGF in tissues and dampen its many ill effects. In the thymus, deletion of PAPPA maintained just enough IGF to sustain production of T cells without consuming precursor cells, thereby preventing the degeneration of the thymus.
"Controlling the availability of IGF in the thymus by targeted manipulation of PAPPA could be a way to maintain immune protection throughout life," Dr. de Vallejo said. "This study has profound implications for the future study of healthy aging and longevity."
MONDAY July 13, 2009---------------------------News Archive / Return to News Alerts
Human Sperm Created From Embryonic Stem Cells
Human sperm have been created using embryonic stem cells for the first time in a scientific development which will lead researchers to a better understanding of the causes of infertility
Researchers led by Professor Karim Nayernia at Newcastle University and the NorthEast England Stem Cell Institute (NESCI) have developed a new technique which has made the creation of human sperm possible in the laboratory.
The work is published today (8th July 2009) in the academic journal Stem Cells and Development.
The NorthEast England Stem Cell Institute (NESCI) is a collaboration between Newcastle and Durham Universities, Newcastle NHS Foundation Trust and other partners.
Professor Nayernia says: “This is an important development as it will allow researchers to study in detail how sperm forms and lead to a better understanding of infertility in men why it happens and what is causing it. This understanding could help us develop new ways to help couples suffering infertility so they can have a child which is genetically their own.”
“It will also allow scientists to study how cells involved in reproduction are affected by toxins, for example, why young boys with leukaemia who undergo chemotherapy can become infertile for life and possibly lead us to a solution.”
The team also believe that studying the process of forming sperm could lead to a better understanding of how genetic diseases are passed on.
In the technique developed at Newcastle, stem cells with XY chromosomes (male) were developed into germline stem cells which were then prompted to complete meiosis - cell division with halving of the chromosome set. These were shown to produce fully mature sperm, called scientifically In Vitro Derived sperm (IVD sperm).
In contrast, stem cells with XX chromosomes (female) were prompted to form early stage sperm, spermatagonia, but did not progress further. This demonstrates to researchers that the genes on a Y chromosome are essential for meiosis and for sperm maturation.
The IVD sperm will not and cannot be used for fertility treatment. As well as being prohibited by UK law, the research team say fertilization of human eggs and implantation of embryos would hold no scientific merit for them as they want to study the process as a model for research.
“While we can understand that some people may have concerns, this does not mean that humans can be produced ‘in a dish’ and we have no intention of doing this. This work is a way of investigating why some people are infertile and the reasons behind it. If we have a better understanding of what’s going on it could lead to new ways of treating infertility,” adds Professor Nayernia.
The Newcastle University team have developed a method for establishing early stage sperm from human embryonic stem cells in the laboratory.
The embryonic stem cells were cultured in a new medium containing vitamin A derivative (retinoic acid), in a new technique established by the team. Based on this technique, the cells differentiated into germline stem cells.
These expressed a protein which was stained with a green fluorescent marker and they were separated out by FACSTM (Fluorescence-activated cell sorting) using a laser.
After further differentiation, these in vitro derived germline stem cells expressed markers which are specific to primordial germ cells, spermatogonial stem cells, meiotic (spermatocytes) and post meiotic germ cells (spermatids and sperm).
These results indicated maturation of the primodial germ cells to haploid male gametes called IVD sperm - characterised by containing half a chromosome set (23 chromosomes).
Video and more information
View here to see a video describing the research to create IVD sperm
ONLINE: Save EXTRA $5 off $50 w/code SEARS50OFF50) at cart, 5/24/09 to 1/31/10
Autism May Be Linked to Mom's Autoimmune Disease
Children of mothers who have autoimmune diseases such as type 1 diabetes, rheumatoid arthritis and celiac disease have up to a three times greater risk for autism, a new study finds.
Although the association between autism and a maternal history of type 1 diabetes and rheumatoid arthritis had been found in earlier research, the researchers behind the new study say that theirs is the first to find a link between autism and celiac disease. People with celiac disease cannot tolerate gluten, a protein in wheat, rye and barley.
"This finding reinforces the suggestion that autoimmune processes are connected somehow with the cause of autism and autism spectrum disorder," said researcher William W. Eaton, chairman of the Department of Mental Health at the Bloomberg School of Public Health at Johns Hopkins University. "This finding is on the pathway of finding the cause of autism."
Eaton noted that there is no clinical significance to the finding but that it could guide future research as scientists try to pin down the cause or causes of autism.
One reason autoimmune diseases might have a role in autism is genetic, Eaton said. Children who are born underweight or premature are at higher risk for autism, and both of these obstetric problems are associated with celiac disease, he added.
"There may be an overlap in the genetics of some of the autoimmune diseases and autism that would not be trivial," he said. "Autism is strongly inherited, but we don't have the faintest idea where. But this may point a flashlight to areas of the genome that connect to autism."
In addition, there might also be environmental triggers that affect the fetus, he said.
The report is published in the July 6 online edition of Pediatrics.
For the study, Eaton's team collected data on 3,325 Danish children diagnosed with autism spectrum disorder, including 1,089 diagnosed with infantile autism. The children were born between 1993 and 2004, and their data was part of the Danish National Psychiatric Registry. Data on family members with autoimmune diseases came from the Danish National Hospital Register.
The researchers found that children whose mothers had autoimmune disease were at a higher risk of developing autism spectrum disorder than children of mothers who did not have these conditions. In addition, the risk of infantile autism was increased in children with a family history of type 1 diabetes.
The increased risk that autoimmune diseases contribute to autism is not huge, Eaton said.
"The increased risk for type 1 diabetes is a little less than two times, for rheumatoid arthritis it's about 1.5 times and for celiac disease it's more than three times," Eaton said. "That's enough to impress an epidemiologist, but not enough to make anybody in the general population start changing their behavior."
Dr. Hjordis O. Atladottir, from the Institute of Public Health at the University of Aarhus in Denmark and the study's lead researcher, said that the findings are important because they support the theory that autism is somehow associated with disturbances in the immune system.
"It is important to emphasize that these results should not cause worry or be unsettling for parents or future parents with any of the above-mentioned diseases," Atladottir said. "The large majority of people affected by an autoimmune disease do not have children with autism."
Autism expert Dr. Jeffrey Brosco, a professor of clinical pediatrics at the University of Miami Miller School of Medicine, said the study reinforces the association between autism and a mother's autoimmune disease or, in the cases of type 1 diabetes, a mother's or father's condition.
"This study confirms that we still don't know what's going on in autism but suggests there is something interesting about autoimmune diseases in parents of children with autism," Brosco said.
Though there seems to be a connection between autism and some parental autoimmune diseases, he said, the mechanism of that interaction is not known. It could be associated with the diseases themselves, it could be that the genes associated with autoimmune diseases and autism are located near each other or it could be that an autoimmune disease changes the quality of a pregnancy, which results in circumstances that increase the risk for autism, Brosco explained.
"These findings are not going to change anything anyone does," Brosco said. "You are not going to treat any patients differently. There is no strong evidence for changing clinical practice, but it does help scientists who are interested in autism understand what are the next questions to ask."
Geraldine Dawson, chief science officer for Autism Speaks, said that evidence is increasing that the immune system might have a role in autism.
"One of the things we are realizing about autism is that it is not one disease but rather many different diseases or conditions that has many different etiologies," Dawson said. "This may be one cause or one risk factor, and if it interacts with a genetic vulnerability, it can increase the risk for autism," she said.
Pregnancy Complications Predict Future Maternal Health
Predicting whether pregnancy complications affect long-term maternal health as well as future pregnancies is at the heart of two studies conducted by researchers in the Department of Obstetrics, Gynecology and Reproductive Sciences at Yale School of Medicine
The first study, published in the journal Hypertension, showed that women who have had two pregnancies complicated by preeclampsia are at a higher risk of hypertension after pregnancy.
Working in collaboration with the University of Copenhagen in Denmark, senior author Michael Paidas, M.D., and his team conducted a retrospective study of over 11 million women who gave birth in Denmark from 1978 to 2007. Their findings showed that among women with preeclampsia, a complication of pregnancy linked to life-threatening cardiovascular disease, the risks of subsequent hypertension risks were compounded with each affected pregnancy. Only healthy women without any other previously identified medical problems were included in the study.
"The only reliable treatment for preeclampsia is delivery of the baby," said Paidas, associate professor and co-director of Yale Women and Children's Center for Blood Disorders, Department of Obstetrics, Gynecology & Reproductive Sciences. "But while delivery may ‘cure' preeclampsia in the moment, these mothers are at high risk of chronic hypertension, type 2 diabetes mellitus and blood clots for the rest of their lives. Pregnancy acts like a natural stress test for women."
Paidas said the research adds to growing data on the link between hypertensive pregnancy disorders, diabetes, cardiovascular disease and maternal death. Paidas and the research team are conducting ongoing studies to explore the genetic links between pregnancy complications, cardiovascular disease and diabetes.
"Physicians and other healthcare professionals should be encouraged to include the history of a woman's pregnancy outcomes when estimating the risk of cardiovascular disease," said Paidas. "Identifying women soon after a hypertensive pregnancy will alert care providers to the increased risks of heart disease, diabetes and blood clotting and allow prompt intervention." In light of this new information, Paidas also urges care providers to exercise caution when prescribing oral contraceptives to women with hypertensive pregnancy complications.
In a second study published in the journal Obstetrics & Gynecology, using the same Danish Registry, Paidas and his team found that preterm delivery, preeclampsia and low-birth weight tend to recur and predispose to each other in a second pregnancy. The severity of the complication in the first pregnancy further increases these risks.
For example, women whose first delivery occurred full term had a 2.7% risk for having a preterm delivery in the second pregnancy. However, if their first pregnancy resulted in a delivery between 32 and 36 weeks of gestation, the risk of a preterm delivery in the second pregnancy increased to 14.7%. Similarly, if their first pregnancy resulted in an even earlier preterm delivery- between 28 and 32 weeks of gestation-the risk of a preterm delivery in the second pregnancy increased to 25.4%. Delivery between 20 and 27 weeks in the first pregnancy doubled the risk for delivering a baby that was small for gestational age in the second pregnancy.
"Our data from this study suggest that spontaneous preterm delivery, preeclampsia, low fetal growth, placental abruption and stillbirth in a first and second pregnancy are interrelated," said Paidas. "Perhaps they all may be features of a ‘placenta-associated syndrome.' Healthy women with a significant pregnancy complication that is considered part of the placenta-associated syndrome are vulnerable in the second pregnancy. Therefore care providers should tailor surveillance, prevention and/or treatment interventions in these patients."
Collaborators on the study published in Hypertension include first author Jacob A. Lykke, M.D., and Jens Langhoff-Roos, M.D. of Rigshospitalet in Copenhagen, Denmark; Elizabeth Triche of Yale School of Public Health; Edmund Funai, M.D. also of Yale's Department of Obstetrics, Gynecology and Reproductive Sciences; and Baha Sibai, M.D. of University of Cincinnati College of Medicine.
Lykke and Langhoff-Roos collaborated with Paidas on the study published in Obstetrics & Gynecology.
Save $5 off $50 with coupon code KMART5OFF50 at Kmart.com, no expiration
Diets Bad for The Teeth Are Also Bad for The Body
Dental disease may be a wake-up call that your diet is harming your body
"The five-alarm fire bell of a tooth ache is difficult to ignore," says Dr. Philippe P. Hujoel, professor of dental public health sciences at the University of Washington School of Dentistry. Beyond the immediate distress, dental pain may portend future medical problems. It may be a warning that the high-glycemic diet that led to dental problems in the short term may, in the long term, lead to potentially serious chronic diseases.
Hujoel reviewed the relationships between diet, dental disease, and chronic systemic illness in a report published July 1 in The Journal of Dental Research. He weighed two contradictory viewpoints on the role of dietary carbohydrates in health and disease. The debate surrounds fermentable carbohydates: foods that turn into simple sugars in the mouth. Fermentable carbohydrates are not just sweets like cookies, doughnuts, cake and candy. They also include bananas and several tropical fruits, sticky fruits like raisins and other dried fruits, and starchy foods like potatoes, refined wheat flour, yams, rice, pasta, pretzels, bread, and corn.
One viewpoint is that certain fermentable carbohydrates are beneficial to general health and that the harmful dental consequences of such a diet should be managed by the tools found in the oral hygiene section of drugstores. A contrasting viewpoint suggests that fermentable carbohydrates are bad for both dental and general health, and that both dental and general health need to be maintained by restricting fermentable carbohydrates.
The differing perspectives on the perceived role of dietary carbohydrates have resulted in opposing approaches to dental disease prevention, Hujoel notes, and have prompted debates in interpreting the link between dental diseases and such systemic diseases as obesity, diabetes, and some forms of cancer.
Over the past twenty years or so, Hujoel says, people have been advised to make fermentable dietary carbohydrates the foundation of their diet. Fats were considered the evil food. A high-carbohydrate diet was assumed to prevent a number of systemic chronic diseases. Unfortunately, such a diet - allegedly good for systemic health - was bad for dental health. As a result, cavities or gingival bleeding from fermentable carbohydrates could be avoided only -- and not always successfully, as Hujoel points out -- by conscientious brushing, fluorides, and other types of dental preventive measures. When these measures are not successful, people end up with cavities and gum disease.
Hujoel observed that the dental harms of fermentable carbohydrates have been recognized by what looks like every major health organization. Even those fermentable carbohydrates assumed to be good for systemic health break down into simple sugars in the mouth and promote tooth decay. All fermentable carbohydrates have the potential to induce dental decay, Hujoel notes.
But what if fermentable carbohydrates are also bad for systemic health? Hujoel asks. What if dietary guidelines would start incorporating the slew of clinical trial results suggesting that a diet low in fermentable carbohydrates improves cardiovascular markers of disease and decreases body fat? Such a change in perspective on fermentable carbohydrates, and by extension, on people's diets, could have a significant impact on the dental profession, as a diet higher in fat and protein does not cause dental diseases, he notes. Dentists would no longer be pressed to recommend to patients diets that are bad for teeth or remain mum when it comes to dietary advice. Dentists often have been reluctant, Hujoel says, to challenge the prevailing thinking on nutrition. Advising patients to reduce the amount or frequency of fermentable carbohydrate consumption is difficult when official guidelines suggested the opposite.
The close correlation between the biological mechanisms that cause dental decay and the factors responsible for high average levels of glucose in the blood is intriguing. Hujoel explains that eating sugar or fermentable carbohydrates drops the acidity levels of dental plaque and is considered an initiating cause of dental decay.
"Eating these same foods, he says, is also associated with spikes in blood sugar levels. There is fascinating evidence that suggests that the higher the glycemic level of a food, the more it will drop the acidity of dental plaque, and the higher it will raise blood sugar. So, possibly, dental decay may really be a marker for the chronic high-glycemic diets that lead to both dental decay and chronic systemic diseases. This puts a whole new light on studies that have linked dental diseases to such diverse illnesses as Alzheimer's disease and pancreatic cancer."
The correlations between dental diseases and systemic disease, he adds, provide indirect support for those researchers who have suggested that Alzheimer's disease and pancreatic cancer are due to an abnormal blood glucose metabolism.
The hypotheses on dental diseases as a marker for the diseases of civilization were postulated back in the mid-20th century by two physicians: Thomas Cleave and John Yudkin. Tragically, their work, although supported by epidemiological evidence, became largely forgotten, Hujoel notes. This is unfortunate, he adds, because dental diseases really may be the most noticeable and rapid warning sign to an individual that something is going awry with his or her diet.
"Dental problems from poor dietary habits appear in a few weeks to a few years," Hujoel explains. "Dental improvement can be rapid when habits are corrected. For example, reducing sugar intake can often improve gingivitis scores (a measurement of gum disease) in a couple of weeks. Dental disease reveals very early on that eating habits are putting a person at risk for systemic disease. Since chronic medical disease takes decades to become severe enough to be detected in screening tests, dental diseases may provide plenty of lead-time to change harmful eating habits and thereby decrease the risk of developing the other diseases of civilization."
In planning a daily or weekly menu, Hujoel suggests: "What's good for your oral health looks increasingly likely to also benefit your overall health."