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In Northeast, Weather Changes May Mean More Ticks, Earlier: MedlinePlus

In Northeast, Weather Changes May Mean More Ticks, Earlier: MedlinePlus

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From the National Institutes of HealthNational Institutes of Health






In Northeast, Weather Changes May Mean More Ticks, Earlier

Warming trend could affect the spread of Lyme disease, research suggests
Friday, February 27, 2015
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FRIDAY, Feb. 27, 2015 (HealthDay News) -- Ticks in the northeastern United States are showing up earlier in the spring and expanding their range because of warmer temperatures over the past two decades, experts say.
Although the Northeast is currently contending with record-breaking cold, the trend over the past 19 years has been toward warmer temperatures, the researchers explained. And this is enabling black-legged ticks that carry Lyme disease and other infections to begin feeding several weeks earlier than usual, the investigators found.
This could increase the risk for Lyme disease over the coming decades, the researchers said.
"The risk is changing with climate change. We need to prepare ourselves for tick avoidance education earlier in the season," said research co-author Richard Ostfeld, a senior scientist with the Cary Institute of Ecosystem Studies in Millbrook, N.Y.
"The fact of the matter is that avoidance of infected ticks is the only game in town," Ostfeld said.
The institute sits in the middle of tick country near the Hudson River, about 90 minutes upstate from New York City. In one of two new studies, researchers analyzed statistics gleaned from tens of thousands of mice and chipmunks trapped in the area between 1994 and 2012.
Tick season began earlier by nearly three weeks in warmer years -- from early June to late May, Ostfeld said.
Of course it's tough to definitely prove that climate change is causing a boom in tick populations. But Ostfeld believes that if temperatures continue to climb, tick season may begin even earlier. "Within a few decades, it will shift all the way to early May," he said.
The nymph stage of development -- when ticks are the size of a poppy seed -- is when ticks are the greatest threat to humans. Nymphs are "the guys who make us sick and are responsible for the majority of human cases of Lyme disease," Ostfeld said.
Besides Lyme disease, black-legged ticks can cause babesiosis and anaplasmosis, both potentially life-threatening infections, and encephalitis, an inflammation of the brain, the study authors noted.
Lyme disease is a major public health threat in the Northeast and Midwest, the researchers pointed out.
But warming temperatures are making it easier for ticks to survive in higher altitudes and northern areas that would normally be too cold for them, the researchers concluded after reviewing scientific research.
"Lyme is expanding geographically, moving northward and moving up in elevation," Ostfeld said. This means it's likely to spread into western New York (Syracuse, Buffalo, Rochester), western Pennsylvania (Pittsburgh), southern Canada (Quebec and Ontario) and the mountains of New England, he said.
Sam Telford, a professor of infectious disease and global health at Tufts University in Boston, praised the study and said it doesn't exaggerate the risk of climate change.
But Telford cautioned that a lot can happen over decades.
"The Lyme disease epidemic started in the early 1970s, 40 years ago," he said. "By 2040, we will have a vaccine, and we will have better repellents and insecticides."
What about this spring in the Northeast? It won't necessarily be a good year for people who want to avoid Lyme disease, he said.
"A lot of people think the silver lining is that hopefully the ticks will get clobbered because it's so cold. But we don't find evidence of cold weather conditions having an effect on tick populations," Telford said.
Also, he said, a heavy layer of snow can provide a protective blanket for ticks on the ground.
Ostfeld's advice for keeping ticks at bay once the snow melts: "Use a DEET repellent, the same ones you'd use for mosquitos. Do tick checks if you've been out hiking or walking your dog in the woods or shrubs. Pull them off before they bite you for very long. Wear long pants with closed shoes."
Also, learn about the early symptoms of Lyme disease, he said. These include a rash at the site of the tick bite, fatigue, chills, fever and muscle and joint aches, according to the U.S. Centers for Disease Control and Prevention.
The studies were published Feb. 18 in the journal Philosophical Transactions of the Royal Society B.
SOURCES: Richard Ostfeld, Ph.D., senior scientist, Cary Institute of Ecosystem Studies, Millbrook, N.Y.; Sam Telford, Sc.D., professor, infectious disease and global health, Tufts University, Boston; Feb. 18, 2015, Philosophical Transactions of the Royal Society B
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Use of Long-Acting Birth Control Rises Fivefold in a Decade: CDC: MedlinePlus

Use of Long-Acting Birth Control Rises Fivefold in a Decade: CDC: MedlinePlus

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From the National Institutes of HealthNational Institutes of Health




Use of Long-Acting Birth Control Rises Fivefold in a Decade: CDC

IUDs and implants among the safest, most effective forms of contraception, experts say
Tuesday, February 24, 2015
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TUESDAY, Feb. 24, 2015 (HealthDay News) -- The use of long-acting birth control methods such as IUDs or under-the-skin implants jumped fivefold between 2002 and 2011, according to a new U.S. government report.
Among U.S. women aged 15 to 44, the use of these long-term but reversible contraceptives rose from 1.5 percent in 2002 to 7.2 percent in 2011-2013, says the report from the U.S. Centers for Disease Control and Prevention.
Researchers from the agency's National Center for Health Statistics (NCHS) believe that these methods are gaining in popularity because of their proven ability to prevent unintended pregnancies.
An easing of concerns about safety may be playing a role, too.
IUDs (intrauterine devices) were commonly used by women in the 1970s, until safety issues led to a decline in their use. However, since then, IUDs have improved in quality, experts say.
Also, over the past 20 years, contraceptive implants were approved whose effects last for years, the researchers noted.
All of this means that long-acting contraceptives now "represent a fast-growing segment of contraception use by U.S. women," said lead researcher Amy Branum, chief of the reproductive statistics branch at the NCHS.
The rise in use of long-acting contraceptives might "also be beneficial in reducing unintended pregnancies," especially among women aged 20 to 34, Branum said. She said future research is needed to confirm that, however.
Dr. Deborah Nucatola, senior director of medical services at Planned Parenthood Federation of America, agreed.
"This study shows that more women are choosing the IUD and implants, which are great birth control options for women who want the best possible pregnancy prevention and aren't yet ready to start a family," she said.
IUDs and implants are safe for most women, Nucatola said. That includes teens and women who have not yet had children, she added, and the contraceptives are an especially good option for young women who want to delay starting their families for a few years.
One big advantage of these methods: Women do not have to remember to take a pill every day. "Once an IUD or implant is inserted, you can pretty much just forget about it," Nucatola said.
She cautioned, however, that these methods do not protect women from sexually transmitted diseases.
"So, using condoms in addition to another form of birth control is the best way to prevent both pregnancy and STDs," she said.
The new report, released Feb. 24, found that long-acting contraception is most popular for women ages 25 to 34 (11 percent said they used a long-acting form of birth control), and less popular among women aged 15 to 24 (5 percent) or those between 35 and 44 (again, about 5 percent).
Women who have already had at least one baby are more likely to use a long-acting contraceptive than women who have not yet had children, the NCHS report found. There's also less difference now than in the past in usage rates between racial and ethnic groups, the CDC team said.
Dr. Jill Rabin is co-chief of the division of ambulatory care in the Women's Health Programs-PCAP Services at North Shore-LIJ Health System in New Hyde Park, N.Y. She believes that long-acting birth control methods are among "the most reliable and safest methods of contraception."
Rabin noted that every year in the United States there are more than 500,000 unintended pregnancies, half of which end in abortion. Statistics like those are prompting health workers everywhere to urge women to try long-acting forms of birth control, she said.
"We are trying to encourage women to use the safest, most effective methods," she said.
SOURCES: Amy Branum, Ph.D., chief, reproductive statistics branch, National Center for Health Statistics, U.S. Centers for Disease Control and Prevention; Deborah Nucatola, M.D., senior director of medical services, Planned Parenthood Federation of America; Jill Rabin, M.D., co-chief, division of ambulatory care, Women's Health Programs-PCAP Services, North Shore-LIJ Health System, New Hyde Park, N.Y.; Feb. 24, 2015, report, Trends in Long-acting Reversible Contraception Use Among U.S. Women Aged 15-44
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Hip Injuries and Disorders Update

Hip Injuries and Disorders Update



Hip Injuries and Disorders Update

New on the MedlinePlus Hip Injuries and Disorders page:
02/25/2015 12:00 PM EST

Survival odds improve with longer stay, study finds
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Weight-Loss Surgery May Lower Some Pregnancy Complications, Raise Others: MedlinePlus

Weight-Loss Surgery May Lower Some Pregnancy Complications, Raise Others: MedlinePlus

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From the National Institutes of HealthNational Institutes of Health




Weight-Loss Surgery May Lower Some Pregnancy Complications, Raise Others

Study finds gestational diabetes less likely, but smaller infants more common
Wednesday, February 25, 2015
WEDNESDAY, Feb. 25, 2015 (HealthDay News) -- After undergoing weight-loss surgery, women are significantly less prone to diabetes during pregnancy but twice as likely to deliver smaller-than-normal infants, a new study suggests.
Swedish scientists found that weight-loss (or "bariatric") surgery before pregnancy lowers the chances of certain complications for mothers and babies but raises the odds for others. They recommended any pregnancy after weight-loss surgery be considered high-risk and receive stricter monitoring.
"The number of women who are obese in early pregnancy has increased dramatically over the last decades," said study author Kari Johansson, a postdoctoral researcher and nutritionist at Karolinska Institute in Stockholm. "Consequently, there has been a dramatic rise in the number of women becoming pregnant after bariatric surgery," she added.
"The positive effects of bariatric surgery on health outcomes -- such as diabetes and cardiovascular disease -- are reasonably well-studied, but less is known about the effects on pregnancy and [post-delivery] outcomes," Johansson pointed out.
The study was published online Feb. 26 in the New England Journal of Medicine.
U.S. health officials say more than one-third of American adults are obese, with a body mass index (BMI, a height-weight calculation) of 30 or higher.
Nearly 179,000 obese people underwent weight-loss surgery in the United States in 2013, according to the American Society for Metabolic and Bariatric Surgery. While various techniques may be used, the surgery restricts the amount of food the stomach can hold and/or reduces the intestines' absorption of calories and nutrients from food.
Johansson and her colleagues used data from nationwide Swedish health registries to compare pregnancies between nearly 600 women who had given birth after bariatric surgery and more than 2,300 women who hadn't had the surgery but had the same BMI.
Only 2 percent of women who had weight-loss surgery developed gestational diabetes, compared to 7 percent of the other group, the researchers said. The surgical group was also much less likely to give birth to larger-than-normal babies.
However, the weight-loss surgery group was twice as likely to give birth to babies considered small for their gestational age, and their pregnancies were also of slightly shorter duration. Additionally, the surgical group experienced a slight bump in the rate of stillbirths, the study found.
The investigators didn't examine what might have caused smaller babies among bariatric surgery recipients, or higher stillbirths. But Johannson said those outcomes might be due to reduced nutrient absorption resulting from the surgery, with a fetus not receiving sufficient nutrition.
"It has been reported that gastric bypass [a form of bariatric surgery] increases the risk of protein, iron, vitamin B12, vitamin D and calcium deficiencies," she said. "Also, many women in our study may have been continuing to lose weight when they became pregnant. Continued weight loss may affect fetal nutrition and could influence growth."
Because obesity is linked to poor outcomes for expectant mothers and babies -- including birth defects, gestational diabetes, high blood pressure, premature birth and even childhood obesity -- efforts to lose weight before pregnancy are important, said Dr. Aaron Caughey, chair of the department of obstetrics and gynecology at Oregon Health and Science University's School of Medicine.
But Caughey, who wrote an editorial accompanying the new research, said women considering weight-loss surgery should make the decision based on the long-term health benefits of the procedure -- not on potential pregnancy-related benefits.
"I don't think pregnancy should be the thing that tips the scale," said Caughey. "I don't think the evidence from this study is enough to say now that you should absolutely get this surgery so you have a better pregnancy outcome."
Caughey agreed with the researchers that any pregnancy occurring after weight-loss surgery merits a higher level of monitoring and should be considered high-risk.
He also noted that some experts advise women who undergo weight-loss surgery before pregnancy to delay conceiving until 12 to 24 months after the procedure, the period when the most rapid weight loss occurs.
"I think a conversation with someone who takes care of complicated pregnancies, a maternal-fetal medicine doctor, is a good idea," Caughey said.
SOURCES: Kari Johansson, Ph.D., postdoctoral researcher and nutritionist, Karolinska Institute, Stockholm, Sweden; Aaron B. Caughey, M.D., Ph.D., chair, department of obstetrics and gynecology, and associate dean, Women's Health Research and Policy, Oregon Health and Science University School of Medicine, Portland, Ore.; Feb. 26, 2015, New England Journal of Medicine, online
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Common Infant and Newborn Problems Update

Common Infant and Newborn Problems Update



Common Infant and Newborn Problems Update

New on the MedlinePlus Common Infant and Newborn Problems page:
02/27/2015 02:00 PM EST

Expert offers tips on lowering chances of episodes, knowing when to worry
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ADHD May Raise Odds for Premature Death: MedlinePlus

ADHD May Raise Odds for Premature Death: MedlinePlus

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From the National Institutes of HealthNational Institutes of Health




ADHD May Raise Odds for Premature Death

Risk is small, but a sign the disorder is a serious problem, experts say
Thursday, February 26, 2015
WEDNESDAY, Feb. 25, 2015 (HealthDay News) -- People with attention-deficit hyperactivity disorder (ADHD) are more than twice as likely to die prematurely as those without the common disorder, a new study finds.
The risk is small, but it's a clear indication that the disorder is a serious problem, the researchers said.
In a study of more than 2 million people, Danish researchers found that accidents were the most common cause of premature death among people with ADHD. And the risk was significantly higher for women and those diagnosed in adulthood, the researchers added.
"Our results add to the overwhelming existing evidence that ADHD is a true disorder and should not be taken lightly," said lead researcher Dr. Soren Dalsgaard, a senior researcher at Aarhus University.
Still, Dalsgaard stressed that the actual number of premature deaths among those with ADHD was small. "Although ADHD doubles the risk, it is important to note that the absolute risk is very low," he said. Out of more than 32,000 people with ADHD, 107 died early, he noted.
ADHD is a neurodevelopmental disorder that affects at least 11 percent of American children aged 4 to 17, according to the U.S. Centers for Disease Control and Prevention. They tend to be inattentive, impulsive and hyperactive, which can cause them to struggle academically and socially. The disorder often lingers in adulthood.
The new study was published online Feb. 26 in The Lancet.
"It's common for people with ADHD to be impulsive and act without thinking, which can lead to accidents," said Stephen Faraone, author of an accompanying journal editorial.
Faraone agreed with Dalsgaard that the risk of premature death related to ADHD is small. "But the increase is another sign that this is a serious disorder that needs to be taken seriously," he said.
Treating ADHD is the best way to reduce the risk of dying early, added Faraone, director of child and adolescent psychiatry research at SUNY Upstate Medical University in Syracuse, N.Y.
Treatments can include medication, psychotherapy, training or a combination of treatments, according to the U.S. National Institute of Mental Health.
For the study, Dalsgaard and colleagues collected data on nearly 2 million people included in a large Danish registry who were followed from their first birthday to 2013. Maximum follow-up was 32 years.
More than 32,000 of the people had ADHD. Over the years, 107 people with ADHD died. They were about twice as likely to die prematurely as people without the disorder, even after the researchers took into account factors such as sex, family history of mental problems and parents' age and education.
Accidents were responsible for more than half of the 72 deaths for which there was a known cause.
The risk of dying prematurely rose along with age at ADHD diagnosis. People diagnosed at age 18 or older were more than four times as likely to die early, compared with those without the condition. In contrast, children diagnosed before age 6 had about double the risk of dying prematurely, compared with those without ADHD, researchers say.
In addition, girls and women with ADHD had a higher risk of an early death, compared with boys and men with the condition, the study team found.
Research has shown that ADHD often occurs with other behavioral problems, Dalsgaard said. These can include a substance use disorder, oppositional defiant disorder (a pattern of angry/irritable mood and defiant behavior) or conduct disorder (disruptive and violent behavior and problems following rules), he said.
When ADHD was combined with all three disorders, the odds for premature death were more than eight times higher than for people without ADHD or a co-existing behavioral disorder, the researchers noted.
"ADHD has huge impacts on everyday life, and people with ADHD and their families deserve that this is acknowledged," Dalsgaard said.
SOURCES: Soren Dalsgaard, M.D., Ph.D., senior researcher, Aarhus University, Denmark; Stephen Faraone, Ph.D., professor, psychiatry, director, child and adolescent psychiatry research, SUNY Upstate Medical University, Syracuse, N. Y.; Feb. 26, 2015, The Lancet, online
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Scientists map memorable tunes in the rat brain

Scientists map memorable tunes in the rat brain



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Scientists map memorable tunes in the rat brain

NIH-funded study helps understand how brain remembers everyday sensations
Lights, sound, action: we are constantly learning how to incorporate outside sensations into our reactions in specific situations. In a new study, brain scientists have mapped changes in communication between nerve cells as rats learned to make specific decisions in response to particular sounds. The team then used this map to accurately predict the rats’ reactions. These results add to our understanding of how the brain processes sensations and forms memories to inform behavior.
Striatal neurons in the rat brain
Tuning into memories - Scientists mapped and read sound memories in rat brains. Courtesy of Dr. Zador, Cold Spring Harbor Laboratory, N.Y.
“We’re reading the memories in the brain,” said Anthony Zador, M.D., Ph.D., professor at Cold Spring Harbor Laboratory, New York, and senior author of the study, published in Nature. The work was funded by the National Institutes of Health and led by Qiaojie Xiong, Ph.D., a former postdoctoral researcher in Dr. Zador’s laboratory.
“For decades scientists have been trying to map memories in the brain,” said James Gnadt, Ph.D., a program director at the National Institute of Neurological Disorders and Stroke (NINDS), one of the NIH institutes that funded the study. “This study shows that scientists can begin to pinpoint the precise synapses where certain memories form and learning occurs.”
The communication points, or synapses, that Dr. Zador’s lab studied were in the striatum, an integrating center located deep inside the brain that is known to play an important role in coordinating the translation of thoughts and sensations into actions. Problems with striatal function are associated with certain neurological disorders such as Huntington’s disease in which affected individuals have severely impaired skill learning.
“Insights from this work on central synaptic plasticity help us understand how auditory learning can be triggered and maintained, with potential implications for even very complex skills like learning language,” said Christopher Platt, Ph.D., program director at National Institute of Deafness and Other Communications Disorders (NIDCD), another NIH institute that funded the study.
Hearing begins with hair cells in the ear that transform sounds into nerve cell signals sent to the brain where they are processed by the auditory cortex. Most cortical regions, including the auditory cortex, have neurons that send signals down long thin axons to make synaptic connections on neurons in the striatum. The striatum is part of a multiple relay circuit that processes information from multiple cortical areas and returns it back to the cortex. This circuit is critical in skill learning. 
Petr Znamenskiy, Ph.D., a former graduate student in Dr. Zador’s laboratory, previously demonstrated that neurons in the auditory cortex, which code for specific sound frequencies send signals to striatal neurons which in turn drive behavioral decisions during performance of an auditory discrimination task. Some striatal cells were tuned to high frequency sounds and others to low frequency tones.
In the current study, Dr. Zador’s team found that training rats to learn directional movements in response to low frequency sounds increased the strength of the synaptic connections between the auditory cortex and the striatum.
To study these signals, the scientists recorded electrical responses in the striatum to high and low frequency tones. The recordings were made in the rat’s left striatum, which is responsible for rightward movements. Some synapses were found to respond to high frequency tones and others low frequency tones, giving the scientists a tonotopic map of the left striatum of each rat.
The scientists also injected the auditory cortex cells with light-sensitive molecules that enabled them to directly stimulate the axons from the auditory cortex in response to flashes of light rather than sound.
Then the scientists trained the rats. They put the rats in front of three doors. In the first set of experiments, they trained the rats to find food behind the right-side door in response to low frequency tones and behind the left-side door in response to high frequency sounds. Over the course of four training sessions the performance dramatically improved. As a result of learning the relationship between specific sounds and the food location, they were able to find the food faster after each session.
Before each training session, Dr. Zador’s team recorded synaptically generated electrical signals in the left striatum in response to stimulating the axons from the auditory cortex with laser flashes. They found that as the rats performed better, the synapses in the left striatum, which are tuned to low frequency tones and lead to rightward movement, became progressively stronger. In contrast, the strength of the high frequency synapses did not change. Training the rats to respond to visual cues also had no effect on the synaptic strength, confirming the changes were strictly due to hearing low frequency tones and not other sensations.
“We literally watched the synapses listen and learn to respond to very specific sounds over the course of the training,” said Dr. Zador.
The scientists then mapped the synapses by dissecting slices of the left striatum from the trained rats and then inducing axonal activity in different parts of the slices with light flashes. They found that training rats to associate low frequency tones with food behind the right door strengthened communication at synapses near the inside border of the striatum, and the effects decreased as recordings moved toward the outer surface of the striatum.
Next the scientists reversed the training and flipped the map. They taught the rats to find food behind the right-side door for high frequency tones. In this case the synapses toward the outside border of the left striatum, which are responsive to high frequencies and turning toward the right, were strengthened by the training. The results demonstrate that the circuits for learning have specificity for the exact conditions of the task. 
These studies suggest that selective strengthening of certain connections between cortex and striatum provides a general mechanism of how sensory representations guide the selection of motor responses.
“This study is a great example of how the brain can turn senses — sights, sounds, smells — into meaning,” said Dr. Zador.
This work was supported by grants from the NINDS (NS025713) and NIDCD (DC012565).
For more information on brain research, visit:
www.ninds.nih.gov
www.nidcd.nih.gov
The NINDS is the nation’s leading funder of research on the brain and nervous system. The mission of NINDS is to seek fundamental knowledge about the brain and nervous system and to use that knowledge to reduce the burden of neurological disease.
The NIDCD supports and conducts research and research training on the normal and disordered processes of hearing, balance, taste, smell, voice, speech, and language and provides health information, based upon scientific discovery, to the public. For more information about NIDCD programs, visit http://www.nidcd.nih.gov.
About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.
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References

Xiong et al. “Selective corticostriatal plasticity during acquisition of an auditory discrimination task,” Nature, March 2, 2015. DOI: 10.1038/nature14225