December 28, 2008, 11:05 PM CT

Insights into the X chromosome matchmaking

A research group lead by researchers at the University of Warwick has discovered the trigger that pulls together X chromosomes in female cells at a crucial stage of embryo development. Their discovery could also provide new insights into how other similar chromosomes spontaneously recognize each other and are bound together at key parts of analogous cell processes. This is an important mechanism as the binding togetgher of too a number of of too few of a particular chromosome can cause many medical conditions such as Down's Syndrome or Turner's Syndrome.

In our cells most genes are expressed from both types of each chromosome linked gene, but the most notable exception to this rule are X-linked genes in female mammals. During embryo development, in a step necessary to survival, one of the X chromosomes is silenced in each female cell to ensure that the levels of X-derived products are equalized in XX females and XY males, via a process known as X-Chromosome Inactivation (XCI). Recent discoveries have revealed that for that stage in the process to happen the X chromosomes have to quickly pair off (or colocalize) in a way that allows each part of those pairs of X chromosomes to be very close together and be aligned in a particular way. Failure to achieve this close physical colocalization of the two X chromosomes will lead to XCI failure and cell death......... Posted by: Scott      Read more         Source

December 28, 2008, 11:02 PM CT

Cancer drug bortezomib find new uses

Scientists have discovered a new treatment for transplant patients, targeting the antibody-producing plasma cells that can cause organ rejection.

Results of the study are reported in the Dec. 27, 2008, edition of the journal Transplantation

Steve Woodle, MD, and his colleagues observed that a cancer drug bortezomib used to treat multiple myeloma, or cancer of the plasma cells, is effective in treating rejection episodes caused by antibodies that target transplanted kidneys and reversing rejection episodes that did not respond to standard therapies.

B-lymphocytes, or B cells, play a large role in the humoral immune response by making immune proteins that attack transplanted organs.

"We found a body of literature demonstrating that bortezomib works well in suppressing transplant rejection in the laboratory," says Woodle, main author of the study and chief of transplant surgery at UC. "Moreover, it worked well in models of autoimmune diseases".

T-lymphocytes, or T cells, are white blood cells that were usually thought to cause the rejection of transplanted organs.

Woodle and his team began searching for agents that targeted plasma cells in 2005.

"It has become clear that plasma cells and the antibodies they produce play a bigger role in rejection than previously thought, and the development of therapies targeting these cells has lagged," he says. "We realized that current therapies don't target the plasma cells which may produce the antibody, in general"......... Posted by: Janet      Read more         Source

December 28, 2008, 10:58 PM CT

Young People and Alcohol

As the party season approaches, a timely reminder of the issues surrounding the binge drinking culture are again highlighted by research into 'young people and alcohol' a team lead by Professor Christine Griffin, at the University of Bath. The research, funded by the Economic and Social Research Council (ESRC) suggests several considerations for future policy.

Focusing on the role of marketing practices in shaping young people's attitudes to alcohol consumption, the research included analysis of 216 alcohol adverts, both in print and broadcast. While extreme drinking and determined drunkenness appears to be perceived as the norm amongst young people, there is some positive news from the research. Evidence suggests that increases in young people's alcohol consumption is levelling off.

Previously, representations of binge drinking as a source of entertainment, coupled with pervasive coverage of drunken celebrities has increased the social acceptance of binge drinking. Advertising representing the 'coolness' of excessive drinking, along with the increasing use of internet based social networking sites that are used to share images of drunken nights out,, also enable the linkage between alcohol and 'having fun'.

Looking at what steps society may need to take to tackle the scourge of binge drinking, Professor Griffin says, "Top of my list would have to be to stop demonizing and making generalisations about young people and their drinking. We also need to listen and incorporate their views and perspectives." ......... Posted by: Janet      Read more         Source

December 24, 2008, 5:24 AM CT

Don't put all your bets on fish oil

It is established that fish oil protects against deaths from heart problems, but doesn't count on fish oil to provide a clear benefit in heart rhythm problems (arrhythmias).

More funding is urgently needed in this neglected area of nutrient research, say the authors of an accompanying editorial.

Consuming oily fish at least two to four times a week is recommended for patients after a heart attack. But the evidence for the protective effect of fish oil supplements is based on one large trial from over 10 years ago. More recent trials have showed no beneficial effect of fish oil on patient outcomes.

In an attempt to resolve the uncertainty, Professor Ross Tsuyuki and his colleagues from Canada systematically evaluated randomised trials of fish oil as a dietary supplement in the prevention of cardiac deaths and arrhythmias (abnormal electrical activity in the heart that can lead to death), in more than 30,000 participants in 12 studies.

Fish oil was found to be effective at reducing deaths from heart problems, but showed no good evidence of a beneficial effect on arrhythmias or deaths from all causes.

Three of the studies involving over 11,000 participants analysed the effect of fish oil supplementation on the reduction in implantable cardiac defibrillator interventions and reported a neutral effect. Six studies of over 31, 000 patients examined the effect of fish oil on sudden cardiac death and showed no benefit. A further 11 studies showed a 20% reduction in deaths from heart problems......... Posted by: Daniel      Read more         Source

December 24, 2008, 5:16 AM CT

Making the contraceptive pills available without prescription

Making the contraceptive pill available without prescription will not reduce unwanted pregnancies, says an expert in an article published on bmj.com today.

Sarah Jarvis from the Royal College of Physicians argues that it is a lack of daily compliance with taking oral contraceptives which is partly responsible for the high rates of unintended teenage pregnancies in the UK.

Studies have shown that nearly half of all women taking the oral contraceptive pill miss one or more pills in each cycle, and nearly a quarter missed two or more. These women are three times more likely to get pregnant unintentionally than those who take the pill consistently.

She points out that the availability of emergency contraception without prescription has done little to change the rate of teenage pregnancies.

Jarvis believes that the solution lies in long acting reversible contraceptives such as the coil, or those which can be placed under the skin or injected. They last between three months and three years, and because they are not dependent on patients taking them correctly, are much more reliable than oral contraceptives, she adds.

"Increased uptake of reliable, non user-dependent methods, rather than making a potentially unreliable method of contraception more easily available, has to be the key ", she concludes......... Posted by: Emily      Read more         Source

December 23, 2008, 10:34 PM CT

Preventing breast cancer with broccoli

Women should go for the broccoli when the relish tray comes around during holiday celebrations this season.

While it has been known for some time that eating cruciferous vegetables, such as broccoli, cauliflower, and cabbage, can help prevent breast cancer, the mechanism by which the active substances in these vegetables inhibit cell proliferation was unknown until now.

Researchers in the UC Santa Barbara laboratories of Leslie Wilson, professor of biochemistry and pharmacology, and Mary Ann Jordan, adjunct professor in the Department of Molecular, Cellular, and Developmental Biology, have shown how the healing power of these vegetables works at the cellular level. Their research is published in this month's journal Carcinogenesis

"Breast cancer, the second leading cause of cancer deaths in women, can be protected against by eating cruciferous vegetables such as cabbage and near relatives of cabbage such as broccoli and cauliflower," said first author Olga Azarenko, who is a graduate student at UCSB. "These vegetables contain compounds called isothiocyanates which we believe to be responsible for the cancer-preventive and anti-carcinogenic activities in these vegetables. Broccoli and broccoli sprouts have the highest amount of the isothiocyanates......... Posted by: Janet      Read more         Source

December 23, 2008, 10:25 PM CT

Family Depression May Have Lasting Effects On Teens

The country's economic crisis could have lasting effects on children from families that fall into poverty, as per a new paper by scientists from Iowa State University's Institute for Social and Behavioral Research.

Their study of 485 Iowa adolescents over a 10-year period (1991-2001) observed that early socioeconomic adversity experienced by children contributes to poor mental health by the time they become teens -- disrupting their successful transition into adulthood by endangering their social, academic and occupational attainment as young adults.

"The main finding shows the continuity of family adversity over generations -- from family-of-origin to a young adult's family. In other words, it's the transmission of poverty," said K.A.S. Wickrama, an ISU professor of human development and family studies and the study's lead researcher.

"Other articles have shown intergenerational transmission of adversity, but our study also shows the mechanisms that this influence operates through," he said. "We had the luxury of data to investigate that because we have been following 500 Iowa families since 1989".

Wickrama collaborated with Fred Lorenz, ISU University Professor of psychology; Tony Jung, an ISU graduate student in human development and family studies; and Rand D. Conger, a Distinguished Professor of human and community development at the University of California-Davis, on the study. They authored the paper "Family Antecedents and Consequences of Trajectories of Depressive Symptoms from Adolescence to Young Adulthood: A Life Course Investigation," which was reported in the recent issue of the Journal of Health and Social Behavior, a professional journal......... Posted by: JoAnn      Read more         Source

December 22, 2008, 9:46 PM CT

Genes may influence popularity

A groundbreaking study of popularity by a Michigan State University scientist has observed that genes elicit not only specific behaviors but also the social consequences of those behaviors.

As per the investigation by behavioral geneticist S. Alexandra Burt, male college students who had a gene linked to rule-breaking behavior were rated most popular by a group of previously unacquainted peers.

It's not unusual for adolescent rule-breakers to be well-liked - prior research has made that link - but Burt is the first to provide meaningful evidence for the role of a specific gene in this process. The study will appear in an upcoming issue of the Journal of Personality and Social Psychology, which is published by the American Psychological Association.

"The idea is that your genes predispose you to certain behaviors and those behaviors elicit different kinds of social reactions from others," said Burt, assistant professor of psychology. "And so what's happening is, your genes are to some extent driving your social experiences".

The concept - which scientists call "evocative gene-environment correlation" - had been discussed in scientific literature but only in theory. This study is the first to really flesh out the process, establishing clear connections between a specific gene, particular behaviors and actual social situations, she said......... Posted by: Janet      Read more         Source

December 22, 2008, 9:38 PM CT

Weight issues in children starting school

Immigrant children have a greater risk of suffering from overweight and obesity. This is the result of a study from Augsburg with 2306 children examined on starting school. Elisabeth Weber and her coauthors present the results in the current issue of Deutsches rzteblatt International (Dtsch Arztbl Int 2008; 105 [51-52]: 883-9). The doctors recorded not only the age, sex, weight, and height of the children, but also their mother tongue. Their parents had to answer a questionnaire covering sporting activity, amount of television watched, and eating behavior.

German was the mother tongue of 1398 of the children examined. Turkish was the most frequent foreign language (395 children), followed by Russian (183 children). Other languages were subsumed under "other" (419 children). In all, 302 children (13.1%) suffered from overweight and 133 children (4.9%) were obese. The results showed that half of all the children engaged in no sporting activity. In particular, 65% of Turkish speaking children and 59% of Russian speaking children were not in any sporting group. There were also ethnic differences in the amount of television watched. Almost two thirds of Turkish and Russian speaking children watched one to three hours of television per dayabout twice as a number of as Germans. The eating habits of the Turkish children were especially striking. Only 12.4% had five meals a daythe lowest of any group......... Posted by: JoAnn      Read more         Source

December 22, 2008, 9:27 PM CT

Nutritious fast-food kids' meals are scarce

Only 3 percent of kids' meals served at fast-food restaurants met federal dietary guidelines in the first study to examine the nutrient quality of such meals in a major U.S. metropolitan market.

Michigan State University's Sharon Hoerr, a food science and human nutrition researcher with the Michigan Agricultural Experiment Station, teamed up with economist Sharon O'Donnell and pediatrician Jason Mendoza from Baylor College of Medicine in Houston to assess the nutritional status of kids' meals in the Houston market.

The small percentage of meals that did meet dietary guidelines included fruit as a side dish and milk, and nearly all were deli-sandwich meals. They also had about one-third the fat, one-sixth the added sugars, twice the iron and three times the amount of vitamin A and calcium as did meals not meeting the criteria.

"This report is the first to characterize and compare the nutrient quality of all combinations of fast-food kids' meals in a major metropolitan market," Hoerr said. "Because 25 percent of children aged 4 to 8 years consume fast food on a typical day, the diet quality of kids' meals offered by fast-food companies contributes significantly to their overall health and well-being.

"Two trends motivate the need for an evaluation of the nutrient quality of fast-food kids' meals: the increased prevalence of childhood obesity and the amount of food consumed away from home"......... Posted by: JoAnn      Read more         Source