SUNDAY - September 30, 2007----------------------------------------News Archive/Return to Today's News Alerts

Upset Children Need Both Parents To Weigh Differences.
A new study from the University of Illinois in collaboration with North Carolina State University and the University of Michigan, suggests that young children benefit when mothers and fathers differ in their reactions to their child’s negative emotions.

"When a young child is angry, sad, or frustrated, the best scenario seems to be if one parent comforts and problem-solves with the child while the other parent hangs back a bit and gives the child space to process what he’s feeling,” said Nancy McElwain, a U of I assistant professor of human development.

When that happens, the child is more likely to gain experience in understanding and controlling his emotions. He may also benefit from seeing different types of reactions, realize that there are different ways of looking at things, and thus develop more complex thinking about and understanding of emotions, she said.

"We’re hypothesizing that if both parents rush in to help the child, the child doesn’t have a chance to experience negative feelings and learn how to manage them,” she said. Published September/October, 2007 in Child Development.

Prolactin's Possible Role in Breast Cancer.
"Scientists at the Kimmel Cancer Center at Jefferson University in Philadelphia have discovered new molecular evidence of the role of the hormone prolactin in breast cancer. They have found that prolactin, a pituitary hormone that normally stimulates breast development and milk production, initiates a new “signaling pathway” that may regulate the growth and survival of breast cancer cells. Published September/October, 2007 in Molecular Endocrinology.

Controversial Drug DCA to Get First Human Trials.
A potential anti-cancer treatment that attracted massive public interest earlier this year is to be tested on 50 people with brain tumours.

The drug, dichloroacetate (DCA), disables the energy-producing mechanism in cancerous cells, although concerns remain over toxicity and side effects such as nerve damage.

Promising results from animal studies at the University of Alberta in Edmonton, Canada led to attempts by desperate cancer patients to buy DCA - a common lab chemical - online. The US Food and Drug Administration later halted sales of the un
approved drug. Published September 28, 2007 in the New Scientist.

Russian Mother Has "Giant" Baby.
A Russian woman has given birth to a baby weighing 7.75kg (17.5lbs), more than twice the average newborn weight.

The "little" girl, Nadia, was delivered by Caesarean section at a hospital in the Altai region of Siberia, joining eight sisters and three brothers. "We were all simply in shock," reports quoted Nadia's mother, Tatyana Khalina, 43, as saying. "What did the father say? He couldn't say a thing - he just stood there blinking," she said. All her previous babies had weighed more than 5kg (11lb), a local reporter was quoted by the Reuters news agency as saying.

"I ate everything, we don't have the money for special foods so I just ate potatoes, noodles and tomatoes," added Mrs Khalina, who had the child on 17 September. Published September 27, 2007 in BBC News.

Better To Sleep On It.
Nappers concerned that a mid-day snooze might ruin a good night's sleep – fret not! Ongoing research from NewYork-Presbyterian Hospital/Weill Cornell Medical Center may show that not only does napping have little effect on sleep onset, but it may also be beneficial for mental processing the following day.

People over the age of 60 get two hours less sleep than younger individuals, which can impair mental functioning during the day. The researchers believe that a mid-day nap may improve daytime performance and mood in the elderly and in those who don’t get enough rest. The subjects are all "normal sleepers," but the researchers want to learn how napping affects their daily lives and mental functioning.

People who suffer from Delayed Sleep Phase Disorder can't fall asleep until the early morning hours and don’t wake up until the late afternoon. Advanced Sleep Phase Disorder is just the opposite – falling asleep early (around four or five in the afternoon) and waking up in the early morning hours. People who suffer with these sleep disorders find it impossible to break out of this cycle.

Drs. Campbell and Murphy are researching a possible genetic link. The scientists believe that these unusual sleep cycles may be genetically determined. The researchers from the Human Chronobiology Laboratory are collaborating with scientists at Rockefeller University to help locate the genes that may be responsible for the study participants' sleep woes. Published September, 2007 in Weill Cornell Medical College - Science Briefs.


SATURDAY - September 29, 2007----------------------------------------News Archive/Return to Today's News Alerts

Contraception: Progress Brings Hope for New Male Methods.
Will men actually use a new method if researchers make one? Elaine Lissner, director of the nonprofit Male Contraception Information Project, says demand is the least of the problems. "You'll never have all men interested, but attitudes have really changed- studies consistenly show a majority of men would consider it. You have to remember, between condoms and vasectomy, men in the U.S. are already taking care of a third of contraception. Just imagine if they had another non-permanent option."

Among the developments announced at the conference:
Researchers from the University of Pittsburgh and BIOQUAL Inc. showed they could provide contraception in monkeys with no hormones and no shots needed. The monkeys had no moving sperm after they took a compound called CDB-4022, and their fertility bounced back completely by 16 weeks. The researchers hope this will be a new nonhormonal contraceptive that can be taken as a pill; in survey results presented at the conference by the International Male Contraception Coalition, 61% of men listed a nonhormonal drug as their first choice. Safety studies will be the next step.

A testosterone-like pill ("selective androgen receptor modulator") already in human testing as an osteoporosis and muscle-wasting treatment may have a side benefit: it could work as a hormonal contraceptive that could be taken as a pill. Until now, most "male Pill" research has used a combination of shots, implants, or gels. The SARM's industry support (by GTx, Inc.) gives it a good chance at commercialization.

Another androgen that can be taken orally, Dimethandrolone Undecanoate (DMAU), was effective at reducing sperm numbers in rabbits if taken at a low, but not high, dose. Rabbits regained their fertility when they stopped the drug.

Makers of the Intra Vas Device are expected to announce effectiveness data showing "substantial equivalence to traditional vasectomy methods” in a study of 90 men. The Intra Vas Device blocks sperm in the vas deferens, the tube sperm swim through that is cut in vasectomy. The set of plugs can be removed if a man changes his mind, and animal studies have shown that fertility returns if it is removed after short-term use. The next step will be to find funding for long-term studies of effectiveness and fertility return.

Developers of a home sperm test ("SpermCheck") reported excellent results in men. The test perfectly matched more expensive laboratory tests in detecting whether men's sperm count is above or below 200,000-300,000 per millileter, an extremely low number (normal counts are above 20 million per millileter). When this test hits the market, it will help men who are using "do-it-yourself" methods such as simple wet heat and suspensories. It will also allow men who get vasectomies to know when their sperm are cleared out, without going to the doctor. About 1 in 6 American couples uses vasectomy as a contraceptive method, with more than 500,000 men opting for the procedure each year.

Presented September 28, 2007 at the second Future of Male Contraception conference.

Controversial Drug DCA to Get First Human Trials.
A potential anti-cancer treatment that attracted massive public interest earlier this year is to be tested on 50 people with brain tumours.

The drug, dichloroacetate (DCA), disables the energy-producing mechanism in cancerous cells, although concerns remain over toxicity and side effects such as nerve damage.

Promising results from animal studies at the University of Alberta in Edmonton, Canada led to attempts by desperate cancer patients to buy DCA - a common lab chemical - online. The US Food and Drug Administration later halted sales of the unapproved drug. Published September 28, 2007 in the New Scientist.

The Basic Units of Memory.
A molecular "recycling plant" permits nerve cells in the brain to carry out two seemingly contradictory functions – changeable enough to record new experiences, yet permanent enough to maintain these memories over time. The discovery of this molecular recycling plant provides new insights into how the basic units of learning and memory function. Individual memories are "burned onto" hundreds of receptors that are constantly in motion. Duke University Medical Center neurobiologist Michael Ehlers, M.D., Ph.D., describes these receptors as constantly moving around the synapse and often times seeming to disappear or escape.

"This process occurs on a time scale of minutes or hours, so the acquisition of new neurotransmitter receptors and their recycling is an on-going process. Memory loss may result from receptors escaping from the synapse." All this activity takes place on millions of tiny "nubs," or protrusions in the synapses known as dendritic spines. The recycling plants are located within the body of these dendritic spines.

"We believe that the existence of this recycling ability explains in part how individual dendritic spines retain their unique identity amidst this constant molecular turnover," Ehlers said. "The system is simultaneously dynamic and stable."

While these findings should be able to help neurobiologists as they attempt to understand the molecular foundations of learning and memory, Ehlers believes that this knowledge could also be helpful in explaining what happens in certain neurological disorders, such as Alzheimer's disease, schizophrenia, or learning disorders like autism. For example, it appears that in animal models of the early phases of Alzheimer's disease, often before any symptoms become apparent, the dendritic spines gradually lose their ability to transport and recycle the receptors.

"If the receptors don't get recycled, you see a gradual loss of synaptic function that is associated with reduced cognitive ability," Ehlers said. "These dendritic spines are where learning and memories reside. These are the basic units of memory." Published September 19, 2007 in the journal Neuron.

Molecule May Be Smoking Gun in Breast Cancer Metastasis.
Scientists have developed a new way to treat liver failure by somewhat suppressing the immune response by using stem cells taken from the bone marrow. So far the technique has only been tested in animals, but if it works in humans it could help save lives.

Scientists at Massachusetts Institute of Technology (M.I.T.) looked for the snippets, called microRNA, in 18 women with metastatic -- spreading -- breast cancer. Nine of the women had high levels a microRNA called miR-10b. In five women with less-severe cancer, miR-10b was absent.

The researchers then injected mice with miR-10b-active cancer cells. The tumors soon metastasized; in another group of mice given miR-10b-free cancer cells, the tumors stayed put.

How miR-10b could promote metastasis is unknown -- it might, reports Nature News, "hijack the existing cellular pathway designed to turn a blob of cells into a full human, and use this to efficiently move cells around the body." It could also turn out to be a false lead: nine women and a few mice isn't much to go on. But the fact that this was published in Nature hints at its potential significance, and scientists will soon test whether blocking it can stop or slow breast cancer's spread. Published September 26, 2007 at Nature News.

Individual Differences = Shuffled DNA Chunks in Human Genome.
“The focus for identifying genetic differences has traditionally been on point mutations or SNPs — changes in single bases in individual genes,” said Michael Snyder, the Cullman Professor of Molecular, Cellular & developmental Biology, Yale University and senior author of the study. “Our study shows that a considerably greater amount of variation between individuals is due to rearrangement of big chunks of DNA.”

This study was designed to fill in the gaps in the genome sequence and to create a technology to rapidly identify SV between genomes at very high resolution over extended regions. “We were surprised to find that structural variation is much more prevalent than we thought and that most of the variants have an ancient origin. Many of the alterations we found occurred before early human populations migrated out of Africa,” said first author Jan Korbel, a postdoctoral fellow in the Department of Molecular Biophysics & Biochemistry at Yale.

They looked at structural variations that were shared or different, between two females — one of African descent and one of European descent — analyzing their DNA using a novel DNA-based method called Paired-End Mapping (PEM). Point mutations previously were estimated to show 0.1 percent difference between individuals, while this work shows a level of variation two- and five-times higher. “We also found ‘hot spots’ — particular regions where there is a lot of variation,” said Korbel. “While these regions may be still actively undergoing evolution, they are often regions associated with genetic disorder and disease.”

According to the authors, even in healthy people, there are variations in which part of a gene is deleted or sequences from two genes are fused together without destroying the cellular activity with which they are associated. They say these findings show that the “parts list” of the human genome may be more variable, and possibly more flexible, than previously thought. Published September 27, 2007 in Science Express.



FRIDAY - September 28, 2007-------------------------------------------News Archive/Return to Today's News Alerts

Evolution of Female Preference for Younger Males.
The prevailing theory of how women choose a mate runs that women prefer older men, as they provide more security than the average younger man. However, studies in humans and model organisms show that as males age, they accumulate mutations in their germ cells at an increasing rate, reducing their gene quality. In other words, older males may produce relatively poor-quality offspring. To better understand how male age influences female mate preference and offspring quality, scientists from the University of Georgia in Athens, Georgia used a genetic algorythm model to study the effect of age-related increases in male genetic load on female mate preference.

When the scientists incorporated age-related increases in mutations in males into their model, they found that the females evolved a preference for younger males. Females can determine a male's age, but not his inherited genotype or mutation load. However, females evolved age-preferences that led them to mate with males with low mutation loads, showing no preference for males with respect to their somatic quality. These results suggest that germ-line quality, rather than somatic quality, should be the focus of female preference in good genes models. Published September 26, 2007 at the PLoS One.

Oxytocin in the Circadian Timing of Birth.
The molecular components determining the timing for birth are still not completely understood, even with how important management of preterm, post-term and arrested labor are to both mother and the developing fetus.

To test the hypothesis that oxytocin mediates circadian regulation of birth, scientists at the Departments of Obstetrics and Gynecology, Pediatrics and Molecular Biology and Pharmacology, at Washington University School of Medicine, St. Louis, Missouri; and at the Division of Endocrinology at Children's Hospital, Boston, Massachusetts evaluated parturition timing following shifts in light cycles in oxytocin (OT)-deficient mice. In contrast to wild type mice who did not shift their timing of birth following atificially set 6-hour advances or delays in their light cycle, OT-deficient mice delivered at random times of day. Moreover, shifts in the light-dark cycle of pregnant wild type mice had little impact on the pattern of circadian oxytocin release.

Three significant implications arise from these results. First, that the pattern of OT secretion is fixed early in gestation. This oxytocin rhythm doesn't shift with changes in the light cycle during gestation indicating that it is controlled by a circadian pacemaker distinct from the master clock that regulates locomotor activity (this unknown pacemaker is relatively insensitive to changes in the light cycle during gestation).

Second, the circadian pattern of oxytocin regulation is a primary determinant of the circadian timing of labor.

Third, in the absence of oxytocin, the circadian control of birth is lost following a shift in the light cycle so that parturition has a much greater chance of being dysfunctional. These results demonstrate how oxytocin plays a critical role in minimizing labor disruption due to circadian clock resetting. Published September 26, 2007 at the PLoS One.

Stem Cells By Any Other Name.
The word 'embryonic' is being removed from the name of the US Human Embryonic Stem Cell Registry, the National Institutes of Health announced last week. It will be renamed the Human Pluripotent Stem Cell Registry.

The change is due to an executive order by President Bush after he vetoed legislation that wanted to lift some restrictions on federal funding for human embryonic stem-cell research. The executive order is seen as an attempt to downplay the potential of human embryonic stem cells. Its title reflects the presidential turn of a phrase: "Expanding Approved Stem Cell Lines in Ethically Responsible Ways."

Besides removing 'embryonic' from the names of the cell lines that can receive federal research funding — the September 18th announcement intends to award grants to create cell lines without the involvement of embryos, "aggressively pursuing an assessment of the potential of alternative sources of pluripotent stem-cell lines". This upsets many scientists working to create pluripotent stem-cell lines, who say that such an assessment is not possible without research on newly derived embryonic stem-cell lines. "It's not an alternative; these are complementary technologies," says Rudolf Jaenisch at the Whitehead Institute in Cambridge, Massachusetts, who is working to reprogramme non-embryonic cells to be as flexible as embryonic stem cells.

Pluripotency is notoriously imprecise in its meaning. Human embryonic stem cells established as pluripotent, have yet to become all human cell types, says Glyn Stacey, head of the UK Stem Cell Bank in Hertfordshire, which handles stem-cell lines created from embryos as well as those derived from fetal and adult tissues. Despite the controversy, the first non-embryonic stem-cell lines could be added to the registry in the next few months. Published September 26, 2007 in the News at Nature.

Stem Cell Therapy Used To Slow Down Lver Damage.
Scientists have developed a new way to treat liver failure by somewhat suppressing the immune response by using stem cells taken from the bone marrow. So far the technique has only been tested in animals, but if it works in humans it could help save lives.

Potentially a patient could be kept alive longer until a donor organ is found - and the liver would be given the maximum chance to repair itself. The liver is one of the few major organs that is able to regenerate itself. However, the organ cannot cope with the extensive damage inflicted by diseases like chronic hepatitis, or excessive long-term alcohol consumption. At present, the only treatment for severe "end-stage" damage is a transplant - but donor organs are limited, and recipients must rely on powerful drugs to suppress their immune response.

The Massachusetts General Hospital researchers used mesenchymal stem cells (MSCs) - cells extracted from a patient's own bone marrow, that develop into tissues supporting blood cell development in the marrow cavity. MSCs are able to inhibit several immune system activities, apparently by putting a break on the movement of immune cells to areas of damage.

Simply transplanting MSCs into the animals' livers was not effective. However, two methods of delivering molecules secreted by the cells lessened inflammation within the liver and halted cell death. Cycling the blood of rats with liver failure through an external bioreactor containing MSCs also greatly reduced signs of liver failure in the animals, and boosted survival rates from 14% to 71%. Published September 26, 2007 at the PLoS One.

Stem Cells May Breathe New Life Into Lung Therapy.
Lung cells made from embryonic stem cells have been injected into live animals for the first time. All the mouse cells settled in the lungs, raising hopes that the human equivalent could find and repair damage in people with lung disease.

The results boost efforts to use stem cells to fight lung diseases such as chronic obstructive pulmonary disease (COPD). Advances in this area have lagged behind treatments for other organs such as the heart and liver.

In the latest experiments, Sílé Lane of Imperial College London and her colleagues injected the tails of mice with cells called pneumocytes - relatively primitive cells that can mature into several types of lung tissue, including the cells lining the air sacs of the lung. The pneumocytes were derived from mouse embryonic stem cells.

"This latest work is the first time anyone has implanted embryonic stem-cell-derived pneumocytes into animals," says Lane, who presented .... Published September 26, 2007 in New Scientist.

THURSDAY - September 27, 2007-------------------------------------------News Archive/Return to Today's News Alerts

Mutation of COX2 Gene Doubles/Trebles Risk of Ovarian Cancer.
Dr Ana Carina Pereira, a junior scientist in the molecular oncology group at the Portuguese Institute of Oncology, Oporto, Portugal, revealed her research showing that the COX2 gene is responsible for the production of the enzyme COX-2, which plays a crucial role in prostaglandins production. Prostaglandins cause inflammation, pain and fever, as well as a wide range of other physiological conditions. “Although the causes of ovarian cancer are not fully understood yet, inflammation is known to play an important role in the onset of both ovarian and invasive cervical cancer,” she said. “COX-2 has an important role in the inflammatory process, as well as in key steps in tumour development.”

Dr Pereira looked at the distribution and frequency of three different types (genotypes) of the -765G>C COX2 polymorphism: the GG, GC and CC genotypes. An individual genotype is composed of two distinct parts, the inherited sequences from the maternal and paternal genomes. Therefore, for every genotype, there are two copies of the sequence and these copies are called alleles. Alleles may be identical or different. Dr Pereira explained: “The C and G are alleles that can be inherited, one from each parent. As everyone carries two alleles, their genotypes could be a CC, GC or GG genotype. The G allele is the most common, while the CC genotype is rare; therefore, it is usual to pool the GC and CC genotypes together and we call people with these genotypes C allele carriers.

“Our results demonstrated that C allele carriers had a nearly two-fold (1.8) increased risk of developing ovarian cancer. This was even more evident when we stratified our analysis into two groups based on the average age of the patients; the women aged 53 or under had a nearly three-fold (2.8) increased risk of developing ovarian cancer.”

By enhancing the expression of the COX2 gene, apoptosis is inhibited and tumour promotion proliferates and angiogenesis. The reason why the same effect is not observed in cervical cancer is probably due to the different causes of the two cancers. “In the case of cervical cancer we know that the trigger mechanism is an oncogenic virus, HPV (human papillomavirus) and that in ovarian cancer, although not as clearly understood, inflammation and hormonal regulation are credited with playing a role in its development.”

“Although our findings are very interesting and this polymorphism seems to play an important role in cancer development, these are only preliminary results which need to be confirmed with more complete studies, nor only in the Portuguese population but also in other populations. The interesting clue from these results is the importance of this COX-2 enzyme and the therapeutic drugs that may inhibit its activity (such as aspirin and other NSAIDs). Former studies involving NSAIDs and risk for ovarian cancer were not strongly conclusive because the individual variability in the response to preventive drugs was not taken into account. Now we need studies that will confirm whether giving NSAIDs to women with this polymorphism might be of value in both preventing and treating ovarian cancer."
Presented September 26, 2007 at the European Cancer Conference (ECCO 14) in Barcelona, Spain.

Heart disease, colon cancer linked in study.
Patients showing signs of heart disease are at nearly double the risk of also having colon cancer, perhaps because unhealthy habits and inflammation are at the root of both. The association between heart disease, the single leading cause of death in industrialized countries, and the second most common type of cancer was confirmed in a study of more than 600 patients evaluated at the University of Hong Kong. Previous studies have noted the increased likelihood of heart disease and colon cancer in the same patients, the study said. The two illnesses share several risk factors: smoking, high-fat diet, obesity, diabetes, high blood pressure, and sedentary lifestyle.

"Both colorectal (tumors) and (coronary artery disease) probably develop through the mechanism of chronic inflammation," study author Dr. Annie On On Chan of the University of Hong Kong wrote in the Journal of the American Medical Association. Of patients whose examinations showed at least a 50 percent narrowing of one of the coronary arteries feeding the heart, 34 percent also had cancerous colon tumors. That compared to some 20 percent of patients found to have tumors who were free of heart disease.

The family of cholesterol-lowering drugs called statins appear to have a deterrent effect on both illnesses, perhaps because the drugs reduce inflammation. Aspirin also seems to reduce the risk, the study said. There were 1 million new colon cancer cases in 2002 globally, and 500,000 deaths that year from the disease, which is the most common type of malignancy after lung cancer.” Published September 26, 2007 in the Journal of the American Medical Association.

Post Traumatic Stress Hits Adolescent Kids of Cancer Patients.
Children whose parents have cancer often suffer post-traumatic stress symptoms that adults underestimate, Dutch researchers reveal.

"We thought the symptoms would decline after time but even after one to five years after the diagnosis, the children still had symptoms," said Gea Huizinga, a health scientist at the University Medical Centre in Groningen, who led the study. Experts say post traumatic stress disorder symptoms include irritability or outbursts of anger, sleep difficulties, trouble concentrating, extreme vigilance and an exaggerated startle response. A person may initially respond to the trauma with horror or helplessness, then may persistently relive the event.

The study also found that girls seemed to have the most problems, perhaps because they feel responsible for taking on more duties at home with a sick parent, Huizinga said. The team also noted that the effect on children of parents with cancer was bigger than those of parents with serious, chronic diseases as dying from cancer was so possible. Presented September, 2007 at the European Cancer Conference.

Mouse Molars Help Explain The Trouble With Our Wisdom Teeth.
Evolution occurs with genetic change often brought about by ecological interactions, shaping any and all species’ unique physical characteristics and providing for each to adapt to their own biological niche. This is easily identified in mammalian teeth, reflecting what each species eats.

Researchers at the University of Helsinki’s Institute of Biotechnology now more clearly show us how development affects the evolution of teeth. They have devised a simple developmental model to predict aspects of teeth across many species. Kathryn Kavanagh, Jukka Jernvall and Alistair Evans first studied cheek tooth, or molar, development in mice. Similarl to human teeth, mouse molars develop from front-to-back - after the first molar appears, the posterior molars bud sequentially along the jaw. Normally the last molar to develop is the third, or wisdom tooth.

Their research revealed that the size and number of posterior molars depend on previously initiated molars. The mechanism, called an ‘inhibitory cascade’, acts much like a ratchet that cumulatively increases size differences of teeth along the jaw. By quantifying their experiments, the researchers constructed a simple mathematical model with which they can predict relative size and number of molars across many other mouse and rat species. The model accurately predicts tooth proportions and numbers. It will now be possible to identify how development influences evolution, and explain our troublesome wisdom teeth. A weak inhibitory cascade may allow development of the human's last molar in a jaw that is now too small. Published September 27, 2007 in the journal Nature.

Bedouin "Kissing Cousins".
It has been assumed that inbreeding accounts for most infant mortality in demographic research. But analyzing Bedouin villages in Bekaa, Lebanon, where marriage among first cousins is more than twice the national average, a new study finds the greatest single determinant of infant mortality is not related parents – though this is a significant risk – but short birth intervals.

Analyzing a sample of 1,399 Bedouin children, Suzanne E. Joseph of the University of Massachusetts, Dartmouth, examined the mortality rate for infants (< 12 months) and children under the age of five (12-59 months) and found that infants born to first cousins have more than double the odds of dying as infants born to non first-cousins. “While there is a heightened risk of infant mortality associated with consanguinity, even after controlling for socioeconomic and demographic factors, there are also substantial social, economic, and emotional benefits to marrying kin,” Joseph writes. “Women in particular are able to draw upon the support of their family members after marriage, which enhances their position in the domestic unit.”

Among populations with a high level of familial endogamy, there may also be a relatively high risk of recessive disorders which develop in childhood. However, the children of Bedouin first-cousin parents were not significantly more likely to die in childhood, Joseph found. Indeed, the most statistically significant factor in a Bedouin child’s survival – whether the child of first cousins or not – is birth interval, Joseph reveals. For every additional month that passes before the birth of the next child, the odds of infant death decrease by 3.7 percent. Published October, 2007 in CURRENT ANTHROPOLOGY.

WEDNESDAY - September 26, 2007-------------------------------------------News Archive/Return to Today's News Alerts

Mom's Weight Gain May Indicate Male Second Child On the Way.
Researchers analyzed the change in women’s body mass index (BMI) between the first and second pregnancies from the Swedish Birth Registry,( 220,889 women who had successive pregnancies between 1992 and 2004 - live births and stillbirths were included). The male to female sex ratio of the second pregnancy increased linearly with the amount of weight change from the first to second pregnancy, from 1.024 in women who lost more than 1 unit BMI to 1.080 in women who gained 3 or more units (a male to female sex ratio of 1.000 would indicate an equal number of boys and girls being born). The trend was independent of obstetric complications, maternal smoking, parental age, length of the interpregnancy interval and the sex or survival status of the first-born child.

Some preious studies also looked at what factors might influence the sex ratio, but evidence for a particular cause has been weak. Parental smoking, for example, is associated with both lower and higher sex ratios. Maternal nutritional status had been studied, but there was little evidence to support a causal relationship with the sex ratio. One of the hypotheses that the authors of this study wanted to test was whether the increase in maternal obesity in several industrialized countries could play a role in the declining sex ratio. Their study found the opposite - maternal weight gain seemed to favor the birth of boys.

The obesity epidemic does not appear to explain the observed decline in the sex ratio in some industrialized countries. The authors are careful to note that women should not gain weight to try to influence the sex of their baby. “Weight gain before pregnancy carries significant risks to the mother and the baby, and should not be practiced to influence the odds of having a boy,” said Villamor. “Other factors of which weight gain is only an indicator could be at play here.” Published September 24, 2007 in the journal Fertility & Sterility.

If You Want More Babies, Find a Man With a Deep Voice.
Men who have lower-pitched voices have more children than do men with high-pitched voices, researchers have found. And their study suggests that for reproductive-minded women, mate selection favours men with low-pitched voices.

The study offers insight into the evolution of the human voice as well as how we choose our mates. In previous studies, David Feinberg, assistant professor in the Department of Psychology, Neuroscience and Behaviour at McMaster University, and his colleagues have shown that women find deeper male voices to be more attractive, judging them to be more dominant, older, healthier and more masculine sounding. Men, on the other hand, find higher-pitch voices in women more attractive, subordinate, feminine, healthier and younger sounding.

“While we find in this new study that voice pitch is not related to offspring mortality rates,” says Feinberg,” we find that men with low voice pitch have higher reproductive success and more children born to them.” Published September 24, 2007 in the Biology Letters.

Quick-Burning Carbs May Cause Fatty Liver, Do Cause Obesity.
Diets rich in rapidly-digested carbohydrates not only expand waistlines, but may also cause fatty liver, a condition that can lead to liver failure and death, finds a new study in mice. If confirmed in humans, the findings suggest that fatty liver disease - on the upsurge among Americans as a byproduct of the obesity epidemic - may be preventable and possibly treatable through dietary changes.

Researchers, led by David Ludwig, MD, PhD, director of the Optimal Weight for Life program at Children's Hospital Boston, fed mice either a high- or a low-glycemic index diet. High-glycemic index foods, including white bread, white rice, most prepared breakfast cereals and concentrated sugar, raise blood sugar quickly. Low-glycemic index foods, like most vegetables, fruits, beans and unprocessed grains, raise blood sugar slowly. On the high-glycemic index diet, mice ate a type of cornstarch that is digested quickly whereas on the low-glycemic index diet, mice ate a type of cornstarch that is digested slowly. The diets had equal amounts of total calories, fat, protein, and carbohydrate, and the mice were otherwise treated identically.

After six months, the mice weighed the same. However, mice on the low-glycemic index diet were lean, with normal amounts of fat throughout their bodies. Mice on the high-glycemic index diet had twice the normal amount of fat in their bodies, blood and livers. Published September, 2007 in the journal Obesity.

Scientists Discover How Cancer May Take Hold.
A team, led by researchers at the Carnegie Institution, has found a key biochemical cycle that suppresses the immune response, thereby allowing cancer cells to multiply unabated. The research shows how the biomolecules responsible for healthy T-cells, the body’s first defenders against hostile invaders, are quashed, permitting the invading cancer to spread. The same cycle could also be involved in autoimmune diseases such as multiple sclerosis.

The scientists used special molecular “nanosensors” for the work. “We used a technique called fluorescence resonance energy transfer, or FRET, to monitor the levels of, tryptophan, one of the essential amino acids human cells need for viability,” explained lead author Thijs Kaper. “Humans get tryptophan from foods such as grains, legumes, fruits, and meat. Tryptophan is essential for normal growth and development in children and nitrogen balance in adults. T-cells also depend on it for their immune response after invading cells have been recognized. If they don’t get enough tryptophan, the T-cells die and the invaders remain undetected.”

When tryptophan is broken down in the cancer cells, an enzyme (dubbed IDO) forms molecules called kynurenines. This reduces the concentration of tryptophan in the local tissues and starves T-cells for tryptophan. A key finding of the research was that a transporter protein (LAT1), present in certain types of cancer cells, exchanges tryptophan from the outside of the cell with kynurenine inside the cell, resulting in an excess of kynurenine in the body fluids, which is toxic to T-cells.

When tryptophan is broken down in the cancer cells, an enzyme (dubbed IDO) forms molecules called kynurenines. This reduces the concentration of tryptophan in the local tissues and starves T-cells for tryptophan. A key finding of the research was that a transporter protein (LAT1), present in certain types of cancer cells, exchanges tryptophan from the outside of the cell with kynurenine inside the cell, resulting in an excess of kynurenine in the body fluids, which is toxic to T-cells.Published September 25, 2007 in the journal PLoS Biology.

Early Brain Markers for Alzheimer's Disease Discovered.
Researchers using functional magnetic resonance imaging (fMRI) have found a new marker which may aid in early diagnosis of Alzheimer’s disease. “The findings of this study implicate a potential functional, rather than structural, brain marker—separate from atrophy—that may help enhance diagnosis and treatment monitoring of Alzheimer’s patients,” said the study’s lead author, Jeffrey R. Petrella, M.D., associate professor of radiology at Duke University Medical Center in Durham, N.C. “As new therapies for Alzheimer’s disease enter the pipeline over the next five years, early diagnosis will become critical for patient selection,” Dr. Petrella said. “fMRI may play a key role in early diagnosis, when combined with clinical, genetic and other imaging markers.”

While some areas of the brain activate, or turn on their activity, when a person tries to remember something, other areas deactivate, or suppress their activity. Results from this study show that along the spectrum from healthy people at low risk, to people with mild memory problems, to patients with Alzheimer’s disease, there was increasingly impaired activation in the MTL, an area of the brain associated with episodic memory that normally turns on during a memory task. More surprising, however, was increasingly impaired deactivation in the posteromedial cortices (PMC), an area recently implicated with personal memory that normally suppresses its activity during a memory task. The magnitude of deactivation in the PMC was closely related to the level of memory impairment in the patients and significantly correlated with their neuropsychological testing scores.

While previous studies have suggested that MTL activation may be a possible marker of Alzheimer’s, based on the findings, Dr. Petrella and colleagues concluded that, compared to activation in the MTL, deactivation in the PMC may represent a more sensitive marker of early Alzheimer’s disease. “In other words, the brain not only loses its ability to turn on in certain regions, but also loses its ability to turn off in other regions, and the latter may be a more sensitive marker. These findings give us insight into how the brain’s memory networks break down, remodel and finally fail as memory impairment ensues,” Dr. Petrella said.

The next step is to conduct a large, multicenter study to see if fMRI can be combined with other imaging and genetic tests to scan for future disease,” said study co-author P. Murali Doraiswamy, M.D., chief of the Division of Biological Psychiatry and Alzheimer’s clinical trial expert at Duke. “Much like a negative colonoscopy gives you reassurance, a normal fMRI may, in the future, also offer predictive value.” Published October, 2007 in Radiology.

TUESDAY - September 25, 2007-------------------------------------------News Archive/Return to Today's News Alerts

Many baby deaths 'can be stopped'.
"As many as 1,000 stillbirths each year could be prevented if clinicians were able to spot when foetuses were not developing properly, a study suggests. The UK's National Health Sevice's Perinatal Institute will unveil research this week which points to "restricted foetal growth" as the key factor in many stillbirths. If this was picked up in pregnancy, these babies could be delivered earlier and have a greater chance of survival.

Britain has one of the highest stillbirth rates in Western Europe.

The 10-year-study by the Perinatal Institute found that some 40% of the 4,000 babies stillborn each year have growth problems. Of these, around two thirds may have survived if action had been taken. "We are excited about these findings," said the institute's director, Professor Jason Gardosi. "If we can recognise that babies are not growing as they should then they can be further investigated and, if necessary, delivered at the right time, and in a good condition, rather than being left in the womb and at continued risk of dying."

Professor Gardosi said in addition to foetal growth in relation to stillbirth, researchers were also identifying "an issue about resources", particularly when it came to the number of cases midwives must deal with. These remarks chime with statements made by the new president of the Royal College of Obstetricians and Gynaecologists, Professor Sabaratnam Arulkumaran, who believes there are too few consultants and midwives to guarantee the safety of mothers and babies. In a speech next month, he will cite data showing that most babies die during the night when hospitals have fewer consultants on duty. In an interview with the BBC last month, he said he believed there was too much focus currently on allowing women to give birth at home, and not enough attention on improving conditions in hospital where the majority ultimately give birth. Published September 24, 2007 in the BBC News.

Is There Really A ‘Mommy’ Gene In Women?
“Only in recent times have women acquired significant control over their own fertility, and many are preferring not to be saddled with the burden of raising children," says Lonnie Aarssen, a biology professor at Queen's University, Kingston, Ontario in Canada who specializes in reproductive ecology. "The question is whether this is just a result of economic factors and socio-cultural conditioning, as most analysts claim, or whether the choices that women are making about parenthood are influenced by genetic inheritance from maternal ancestors that were dominated by paternal ancestors.”

Dr. Aarssen suggests that because of inherited inclinations, many women when empowered by financial independence are driven to pursue leisure and other personal goals that distract from parenthood. The women who leave the most descendants will be those with an intrinsic drive for motherhood. Over time those genetic traits that influence women away from motherhood will necessarily be 'bred out.'“The drive to leave a legacy through offspring can be side-tracked by an attraction to legacy through other things like career, fame, and fortune – distractions that, until recently, were only widely available to men” Published October, 2007 in the Oikos.

UK Warning on Need For Universal vCJD Blood Screening.
"Although the number of BSE and vCJD cases is dropping, we ignore these diseases at our peril." says Professor James Ironside, from the National CJD Surveillance Unit in Edinburgh, Scotland. England is being challenged by an expert in "mad cow disease", to change the popular perception that the vCJD outbreak of the 1990s was an isolated threat to humans is far from true.

Dr. Ironside believes the disease is still a major threat, despite a drop in deaths. And he is making his remarks warning an international conference that the risk to the blood supply continues. There have been 161 vCJD deaths since the disease emerged in early 1990. "We know that a significant number of people could be infected with vCJD without showing symptoms. However, we do not know how many people may be affected, and there is no cure or treatment."

Until a rapid screening test is developed, unknowing carriers pose a great risk of infecting others through donating blood or having surgical operations, he added. UK blood transfusion centres have tried to reduce the danger of disease being transferred by removing the more risky white blood cells and banning anyone who had already received a transfusion from donating. A public lecture, organised by the University of Edinburgh, will also include a presentation from Professor Marc Turner, a clinical director of the Scottish National Blood Transfusion Service. Published September 24, 2007 in the BBC News.

Hundreds of Genes Controlling Female Fertility Identified.
Researchers at UT Southwestern Medical Center have found nearly 350 genes related to female fertility. Their research may open the door to much wider study in the poorly understood field of infertility. “This study gives us a way to begin to understand the causes of female infertility,” said Dr. Diego Castrillon, assistant professor of pathology and senior author. “It gives us a much more complete list of candidate genes to explore. Before, we didn’t even know where to look.”

The study was done in mice, “but at the molecular level, ovarian biology is very similar in mice and humans,” Dr. Castrillon said. These discoveries might lead the way to eventually allowing clinicians to test whether an infertile woman has problems with a specific gene, allowing for improved diagnostic tests and tailored therapy in the future, said Dr. Castrillon, a specialist in the diagnosis of infertility and other diseases of women. About 13 percent of women suffer from infertility, with the most common cause being dysfunction of the ovary. Researchers suspected genetic links in many cases, Dr. Castrillon said. In mammals, the ovaries go through a developmental stage after birth in which egg cells become nestled in dormant nests called primordial follicles. Later in development, the follicles become activated by a process that researchers don’t fully understand, and at puberty, egg cells begin being released for fertilization.

The researchers focused on a gene called Foxo3, which controls follicle activation. Normally, follicles are activated on a staggered schedule, so an ovary contains follicles at many different stages of development. In female mice genetically engineered to lack Foxo3, the follicles are normal at birth, but later become activated all at the same time. This coordinated maturation meant that the genes controlling follicle growth were all turned on at the same time, making them easier to detect. Published September, 2007 in the journal Genetics.

Possible Genetic Risk for Fetal Alcohol Disorders.
New research in primates suggests that infants and children who carry a certain gene variant may be more vulnerable to the ill effects of fetal alcohol exposure. The findings represent the first evidence of a genetic risk for fetal alcohol spectrum disorder — a condition that is characterized by profound mental retardation in its most severe form, but which is also associated with deficits in learning, attention, memory and impulse. By identifying a genetic marker that might signal susceptibility to these more subtle fetal alcohol-induced problems, the research fills a pressing need, says Mary Schneider, the University of Wisconsin-Madison professor of kinesiology and psychology who led the study. "The big concern used to be the link between fetal alcohol exposure and mental retardation, but today there is increased concern over behavioral problems in these children," says Schneider. "If this genetic marker could provide a way of recognizing the most vulnerable fetal alcohol-exposed children early in life, perhaps we could help them to live more successful and satisfying lives."

The study's results may also help to explain why some children of mothers who drink during pregnancy suffer birth defects, while others seem to escape unharmed. "We know that 60 percent of women of child-bearing age consume alcohol and more than 50 percent of pregnancies are unplanned," she says. "So it doesn't take much to figure out that prenatal exposure to alcohol — at least in the weeks before pregnancy is detected — is substantial." In line with this, the mother monkeys in the study's experimental group consumed the equivalent of just two alcoholic beverages five times a week during breeding and pregnancy. After the infants were born, the scientists recorded their irritability during a standard battery of developmental tests, measured their reactivity to stress when separated from their mothers. What the researchers found is that fetal alcohol-exposed infants who carried a copy of the short form were more irritable and reactive to stress than either control group infants who weren't exposed to alcohol or those who were exposed but had two copies of the gene's long form.

"If a baby is very irritable and stress reactive, one of the things this can interfere with is the caregiver-infant interaction," she says. "In real life, negative events tend to cluster. So if there's alcohol in the environment, there may also be stress. And then if you have an irritable baby, this all could have cascading effects on the child's psychological development." Recognizing that complex behaviors are seldom, if ever, governed by a single gene, Schneider and her colleagues are also investigating other gene alleles for their potential to interact with fetal-alcohol exposure and put children at risk. Published September 21, 2007 in Biological Psychiatry.

MONDAY - September 24, 2007-------------------------------------------News Archive/Return to Today's News Alerts

Mother's Blood Could Offer Insights Into Fetal Health.
"It's amazing that all these pregnant women are walking around with the answers in their blood," said Dr. Jill L. Maron, the study's lead author and an assistant professor of pediatrics at Tufts-New England Medical Center, in Boston. Maron was referring to the fetal genetic material (mRNA) that circulates in a pregnant woman's blood prior to birth. The ability to measure fetal status by taking a sample of the mother's blood "can advance the field of prenatal diagnosis," she said, by foretelling genetic diseases and allowing genetic monitoring of fetal development because it wouldn't require invasive procedures, such as amniocentesis.

Fetal mRNA in the mother-to-be's bloodstream is "dynamic," meaning that the biomarkers expected to be found would vary with time and stage of fetal development, Maron added. DNA is the genetic material that's common to every cell. RNA determines what is transcribed from the DNA to make an eye cell different from, say, a hair cell. "RNA is more real time. RNA changes all the time, according to the stage of development. That dynamic nature is what we're targeting," Maron said.

Before delivery, researchers found the whole blood of nine mothers included fetal genes, such as those for development, sensory perception, and neonatal physiology. The researchers established that the genes found in the mother's blood were unique to the fetus by comparing them to umbilical-cord blood. Finally, within 24 to 36 hours after delivery, the fetal genes were no longer found in the mother's blood, confirmig that they were unique to the fetus. Published September 20, 2007 in the Journal of Clinical Investigation.

Pertussis Vaccine Given at Birth Boosts Immune Response.
Infants vaccinated against pertussis at birth have a powerful immune response that outstrips the immunity seen in babies vaccinated on the normal schedule, a researcher said here.

Most cases of pertussis in infancy occur before the age of four months, when the normal vaccination schedule has only just begun. Because of that, Nicholas Wood, MBBS, of the National Center for Immunization Research and Surveillance in Westmead, Australia and colleagues wondered if the immunization process could begin earlier.

Analysis of his results showed that all of the infants - regardless of age - had an immune response to the vaccine, Dr. Wood said. Moreover, those with the five doses had a higher immune response than those who got four or three. In fact, among infants getting the five-dose regimen, the immune response at two months was significantly higher (at P<0.05) than that seen in the control group at all time points. The question was how the infant immune systems would respond to the vaccine, he said. "They recognized it, they saw it as foreign, and they made antibodies." There were no severe adverse events during the study. Presented September 21, 2007 at the ICAAC Conference.

Horse Umbilical Cord Stem Cells Isolated.
Stem cells have been successfully isolated from the equine umbilical cord. Once collected, these cells (referred to as umbilical cord matrix cells) are then be preserved frozen, cultured, and differentiated into a host of cell lines, including bone, cartilage, fat, and those of the nervous system. Currently, stem cells are obtained from either fat or bone marrow of adult horses and are employed to treat traumatic and degenerative diseases such as bowed tendons, ligament injuries, osteoarthritis, and osteochondral defects (such as osteochondrosis or bone cysts).

"Studies demonstrate that stem cells help tissues regenerate, rather than repair by forming scar tissue," reported Linda Black, DVM, PhD, director of Clinical Development, Vet-Stem, Inc. "Stem cells assist the healing process by decreasing inflammation, providing growth support, and by their ability to develop into other cell types."

Stem cells obtained from extraembryonic (birth) tissues, including the umbilical cord, are obtained non-invasively and early in the life of the horse, and then be banked for future use. Banking equine umbilical cord stem cells avoids the harvesting and processing time required to isolate stem cells from adult fat or bone marrow. "This study is the first to characterize equine umbilical cord matrix cells," reported Black. According to Kathy Mitchell, PhD, Department of Pharmacology and Toxicology, University of Kansas, equine umbilical cord-derived stem cells have the potential to be employed to treat a number of diseases or for tissue engineering. To be published October, 2007 in the journal Biochemical and Biophysical Research Communications.

Why Evolvution Takes More Than One Lifetime.
In a colony of single-celled bacteria, researchers can watch evolution in action. As the cells divide, mutants appear; and under stress, there is a selective pressure that favours some mutants over others, spreading advantageous genetic changes through the population. In principle, precisely the same thing could occur throughout our bodies. Our cells are constantly being replaced in vast numbers: the human body typically contains about a hundred trillion cells, and many billions are shed and replaced every day.

If this happened simply by replication of various specialized cells in each tissue, our tissues would evolve: mutations would arise, and some would spread. In particular, mutant cells that don't do their specialized job so well tend to replicate more quickly than non-mutants, and so gain a competitive advantage, freeloading off the others. In such a case, our wonderfully wrought bodies could grind to a halt.

Taking a closer look, epithelial tissues, for example, retain a population of undifferentiated stem cells, like the unformed cells present in embryos, that have the ability to grow into different types of cells. When replacements are needed, some of these stem cells divide to make transient amplifying cells (TACs). The TACs then divide several times, and evolutionary biologist John Pepper of the University of Arizona in Tucson and his co-workers think that each division produces cells that are a little more developed into mature tissue cells.

All this costs a lot of metabolic energy taken up by each cell, so it is not very efficient. But, researchers say it means the functions of self-replication and proliferation are divided between separate groups of cells. The stem cells replicate, but only a little, and so there's not much chance for mutations to arise or for selective pressure to fix them in place. The proliferating TACS may mutate, but they aren't simply copying themselves, so there isn't any direct competition between the cells to create an evolutionary pressure. As a result, evolution can't get started.

Pepper and colleagues have used computer modelling to show this proposed mechanism can suppress evolution in a long-lived, multicelled organism. One case in which this scheme might not operate, they say, is in the immune system. Here evolution is beneficial, as it introduces adaptations that fight previously encountered invaders. One drawback of this, however, is that it would be expected to make the immune system more prone to cancers. And that seems to be true: leukaemia and lymphoma are cancers associated with the immune system, and they seem to be more common in younger people than many other cancers, suggesting that the failure to suppress evolution allows its problems to show up rather quickly.

The scientists believe their hypothesis could provide new insights into cancers. Conventional wisdom poses that cancer is caused by some genetic mutation leading cells to proliferate uncontrollably, this new idea implies the problem lies with TAC mutations interfering with differentiation — so that a TAC cell ends up just copying itself instead of producing cells on the next rung up on the way to mature tissue cells. Published September 21, 2007 in Nature.