Why lost weight can creep back on
Scientists have discovered why it is often harder to keep weight off than to lose it in the first place.
A team at New York's Columbia University has shown the key is falling levels of the hormone leptin, which controls appetite.
They found that giving people who had recently lost weight injections of the hormone helped them to avoid putting the pounds straight back on. The study features in the Journal of Clinical Investigation.
Concerns over IVF contamination risk
Some children conceived by a common IVF method could be carrying chunks of bacterial DNA in their chromosomes, finds a study in mice
SOME children conceived by a common method of IVF could be carrying chunks of bacterial DNA in their chromosomes, according to a study in mice. The researchers who conducted the work say that such accidental genetic modification would be very rare, but they argue that fertility doctors should take more precautions to exclude it.
Intracytoplasmic sperm injection, or ICSI, is used to help would-be fathers with very low sperm counts or sperm that cannot swim normally. Rather than mixing sperm and eggs in a culture dish as in conventional IVF, technicians take individual sperm and inject them into a woman's eggs. ICSI has been growing in popularity since its debut in 1991, and now accounts for around half of the IVF procedures in many countries, including the UK and the US.
Over the past five years, researchers have experimented with using ICSI to make genetically modified animals by mixing DNA ...
http://tinyurl.com/dd5f7
Pregnancy drug can affect grandkids too
A drug often given to pregnant women to help their babies mature enough to survive can have effects on the subsequent generation, a guinea pig study finds
DOCTORS treating a woman at risk of having a premature baby may inadvertently be affecting her future grandchildren as well. A study in guinea pigs suggests that a drug commonly given to pregnant women to help their babies mature enough to survive can also affect the brains and behaviour of their grandchildren too. The finding raises a difficult dilemma for doctors, for while the drug undoubtedly saves lives, its side effects could last for generations.
Babies normally spend 40 weeks in the womb, but some can survive even if they are born 15 or 16 weeks early. However, their lungs lack enough of a substance called a surfactant to breathe unassisted. So since the 1970s, doctors have been injecting women at risk of having a very premature baby with synthetic glucocorticoid drugs, such as betamethasone, which hasten the development of a fetus's lungs.
A single dose cuts the death rate ...
http://tinyurl.com/8fsek
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'Survival' genes hold key to healthy brains in babies and the elderly
Completing a daily crossword and enjoying a range of activities and interests has long been accepted as a recipe for maintaining a healthy brain in older age, but the reasons for this have never been clear. Now, scientists at the University of Edinburgh are seeking to identify brain's 'survival' genes which lie dormant in unused brain cells, but are re-awakened in active brain cells. These awakened genes make the brain cells live longer and resist traumas such as disease, stroke and the effects of drugs, and are also critical to brain development in unborn babies.
Their findings could lead to the development of smarter drugs or gene therapies to halt the progress of neurological diseases like Alzheimer's and Parkinson's disease and may also explain, scientifically, the benefits to the brain of maintaining an intellectually and physically stimulating lifestyle in later years. Dr Giles Hardingham of the Centre for Neuroscience Research at the University of Edinburgh said: "When brain cells are highly stimulated, many unused genes are suddenly reactivated. We have found that a group of these genes can make the active brain cells far healthier than lazy, inactive cells, and more likely to live a long life. These findings also have implications at the other end of life, where maternal drug taking and drinking can cause these survival genes to be turned off in the brain of unborn babies." Dr Hardingham, who presented this work recently at the prestigious annual meeting for the Society for Neuroscience in Washington DC, explained: "We recently discovered that a critical step in turning on these survival genes involves activating a master genetic controller called CREB. We aim to home in on which of these CREB-controlled genes are crucial in helping the brain cells live longer and become resistant to trauma. By being able to explain at molecular level the basis of brain activity-dependent survival, it will open the way to developing better therapies to help halt the progress of neurological diseases. He added: "Our work also bears relevance to the potential harm that can befall an unborn baby if it is exposed to substances which suppress its brain activity, like alcohol, and certain drugs like Ketamine and PCP (Angel Dust). The brain cells of young, developing brains are particularly reliant on signals from these 'survival' genes, but these signals are suppressed if their mothers are taking drugs or drinking alcohol. "This in turn can lead to serious health problems such as foetal alcohol spectrum disorder, which affects up to one per cent of live births in the UK and can cause mental retardation, behavioural problems and diminished growth. Some of this harm may be reduced or minimized if we know exactly how it is taking place."
Children with heart defects found to benefit from exercise
Exercise restrictions may be unnecessary for most children
A small but compelling pilot study indicates that many children with serious congenital heart disease, who are typically urged to restrict their activity, can improve their cardiovascular function and exercise capacity through a cardiac rehabilitation program. Fifteen of 16 children participating in a 12-week rehabilitation program at Children's Hospital Boston showed significant gains in heart function, researchers report in the December Pediatrics.
Congenital heart defects affect about 8 in 1000 newborns. Due to advances in care, more and more children with these defects are surviving. Many have diminished exercise capacity after the defects are repaired, and some of this reduction is caused by a lack of activity, says Jonathan Rhodes, MD, a cardiologist at Children's who led the study.
"These kids haven't exercised much. They've been told by coaches, doctors, parents and teachers, 'Oh, you can't exercise,'" Rhodes says. "Cardiac rehabilitation is not a component of most pediatric cardiology programs."
Comforting behavior mistaken for movement disorder
Masturbation in young females can mimic paroxysmal dystonic posturing
The comforting behavior of thumb-sucking wouldn't land a 1-year-old girl in a neurologist's office, but the twisting and unusual movements of the comforting act of infantile masturbation can lead parents and physicians to believe a child is suffering from a movement disorder.
An article published in December's Pediatrics describes a dozen cases of young girls who were referred to pediatric movement disorder clinics between 1997 and 2002 for evaluation of paroxysmal (episodic) dystonic posturing, which is characterized by involuntary muscle contractions that force the body into abnormal movements and positions. Many of the children were subjected to invasive testing and medication before neurologists discovered the dystonic-like symptoms were actually normal muscle contractions that accompany masturbation.
OBESITY BEFORE PREGNANCY LINKED TO CHILDHOOD WEIGHT PROBLEMS COLUMBUS , Ohio – A child's weight may be influenced by his mother even before he is actually born, according to new research. Results of the study, which included more than 3,000 children, suggest that a child is far more likely to be overweight at a very young age – at 2 or 3 years old – if his mother was overweight or obese before she became pregnant. A child is also at greater risk of becoming overweight if he is born to a black or Hispanic mother, or to a mother who smoked during her pregnancy.
http://tinyurl.com/d549m
UCLA imaging study of children with autism finds broken mirror neuron system
Findings pinpoint mechanism behind social deficits
New imaging research at UCLA detailed Dec. 4 as an advance online publication of the journal Nature Neuroscience shows children with autism have virtually no activity in a key part of the brain's mirror neuron system while imitating and observing emotions.
Mirror neurons fire when a person performs a goal-directed action and while he or she observes the same action performed by others. Neuroscientists believe this observation-execution matching system provides a neural mechanism by which others' actions, intentions and emotions can be understood automatically.
Symptoms of autism include difficulties with social interaction -- including verbal and nonverbal communication -- imitation and empathy. The new findings dramatically bolster a growing body of evidence pointing to a breakdown of the brain's mirror neuron system as the mechanism behind these autism symptoms.
Chemical used in food containers disrupts brain development
Bisphenol A (BPA) has been linked to damage in developing brain tissue
The chemical bisphenol A (BPA), widely used in products such as food cans, milk container linings, water pipes and even dental sealants, has now been found to disrupt important effects of estrogen in the developing brain.
A University of Cincinnati (UC) research team, headed by Scott Belcher, PhD, reports in two articles in the December 2005 edition of the journal Endocrinology that BPA shows negative effects in brain tissue "at surprisingly low doses."
The research was supported by funding from the National Institutes of Health and the Pediatric Brain Tumor Foundation.
"These new studies are also the first to show that estrogen's rapid signaling mechanisms are active in the developing and maturing brain in regions not thought to be involved with sexual differences or reproductive functions," Dr. Belcher said.
BPA has often been implicated in disease or developmental problems.
