(Press-News.org) Scientists at the Medical College of Wisconsin, in a team led by Carol Everson, Ph.D., professor of neurology, cell biology, neurobiology and anatomy, have discovered abnormalities in bone and bone marrow in rats undergoing chronic lack of sleep. They discovered abnormalities in serum markers of bone metabolism in sleep-deprived rats, which led them to conduct direct measurements of bone parameters; this time in rats experiencing recurrent sleep restriction during a large portion of their young adulthood.
The results show a dramatic imbalance between bone apposition and reabsorption, marked by an arrest in bone formation without reduced absorption. Furthermore, fat in the red marrow is greatly diminished and platelet-generating cells are doubled in number, indicating changes to marrow plasticity. "If the same processes are evoked in humans," said Dr. Everson, "the potential medical implications are far-reaching and may include poor repair of microdamage from activities of daily living, introduction of osteoporotic processes, and changes to progenitor cells that may affect disease predisposition and disease resistance."
The results appear in the September 2012 issue of Experimental Biology and Medicine. http://ebm.rsmjournals.com/content/237/9/1101.full. Co-authors of the paper are Jeffrey M. Toth, Ph.D., professor of orthopaedic surgery at the Medical College of Wisconsin, and Anne Folley, now a graduate student at George Washington University.
The researchers observed changes in intramembranous ossification and marrow hypercellularity resulting from chronic sleep loss. "Marrow fat was greatly diminished and reflected increased blood cell production and differentiation. Our findings of increased megakaryocyte numbers, for example, suggest that there is an increased demand for cell delivery to the circulation consistent with an inflammatory response, and conceivably the promotion of thrombocytosis," said Dr. Everson.
Dr. Steven R. Goodman, Editor-in-Chief of Experimental Biology and Medicine said "With increased life stress due to work-related, financial and other issues a large percentage of us are experiencing difficulties in sleeping. While we know that chronic sleep loss can affect our health little specific information has been available on how it may impact bone formation or loss. Drs. Everson and Toth, together with Anne Folley present exciting results indicating that sleep deprivation in rats arrests new bone formation, decreases fat within the red marrow and increases platelet levels. If true in humans, and I expect that it may be, this work will have great impact on our understanding of the impact of sleep deprivation on osteoporosis and inability to repair bone damage as we age".
### END
Lack of sleep affects bone health and bone marrow activity
2012-09-18
ELSE PRESS RELEASES FROM THIS DATE:
Sea surface temperatures reach record highs on Northeast continental shelf
2012-09-18
During the first six months of 2012, sea surface temperatures in the Northeast Shelf Large Marine Ecosystem were the highest ever recorded, according to the latest Ecosystem Advisory issued by NOAA's Northeast Fisheries Science Center (NEFSC). Above-average temperatures were found in all parts of the ecosystem, from the ocean bottom to the sea surface and across the region, and the above average temperatures extended beyond the shelf break front to the Gulf Stream.
The annual 2012 spring plankton bloom was intense, started earlier and lasted longer than average. This ...
Disability caused by traumatic brain injury in children may persist and stop improving after 2 years
2012-09-18
New Rochelle, NY, September 18, 2012—A child who suffers a moderate or severe traumatic brain injury (TBI) may still have substantial functional disabilities and reduced quality of life 2 years after the injury. After those first 2 years, further improvement may be minimal. Better interventions are needed to prevent long-lasting consequences of TBI in children conclude the authors of a study published in Journal of Neurotrauma, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers. The article is available free on the Journal of Neurotrauma website at http://www.liebertpub.com/neu.
Frederick ...
Scientists conclude high fructose corn syrup should not be blamed for obesity
2012-09-18
SHREWSBURY, MA – A new article published today in International Journal of Obesity found there is no evidence to suggest the current obesity epidemic in the United States can be specifically blamed on consumption of high fructose corn syrup (HFCS).
The commentary concludes that after an extensive review of all available HFCS research, there is overwhelming evidence showing HFCS is nutritionally equivalent to sugar. This opinion is in-line with the American Medical Association and the Academy of Nutrition and Dietetics, both of which concluded that HFCS is not a unique ...
Women speak less when they're outnumbered
2012-09-18
New experiments in group decision making show that having a seat at the table is very different than having a voice.
Scholars at Brigham Young University and Princeton examined whether women speak less than men when a group collaborates to solve a problem. In most groups that they studied, the time that women spoke was significantly less than their proportional representation – amounting to less than 75 percent of the time that men spoke.
The new study is published by the top academic journal in political science, American Political Science Review.
"Women have something ...
UCSB psychologist studies the effects of diagram orientation on comprehension
2012-09-18
(Santa Barbara, Calif.) –– The orientation of a diagram on the page of a textbook may seem inconsequential, but it can have a significant impact on a reader's ability to comprehend the information as presented, according to a team of researchers at UC Santa Barbara, Vanderbilt University, and West Carolina University. Their findings appear in a recent issue of the journal Bioscience.
Focusing on variously formatted cladograms –– also known as phylogenetic trees –– the researchers found that two diagrams may contain the same information, but they aren't necessarily equivalent ...
1 in 3 victims of teen dating violence has had more than one abuser
2012-09-18
COLUMBUS, Ohio - More than one-third of young adults who reported being victims of dating violence as teenagers had two or more abusive partners, a new study suggests.
The study involved 271 college students who recalled dating violence - including physical, sexual and psychological abuse - from ages 13 to 19.
Overall, nearly two-thirds of both men and women reported some type of abuse during their teenage years, which falls in line with other studies.
But it was surprising how many teen victims had two or more abusive partners, said Amy Bonomi, lead author of the ...
RUB researchers clarify catalysis mechanism of cell growth protein Ras
2012-09-18
Proteins accelerate certain chemical reactions in cells by several orders of magnitude. The molecular mechanism by which the Ras protein accelerates the cleavage of the molecule GTP and thus slows cell growth is described by biophysicists at the Ruhr-Universität Bochum led by Prof. Dr. Klaus Gerwert in the Online Early Edition of the journal PNAS. Using a combination of infrared spectroscopy and computer simulations, they showed that Ras puts a phosphate chain under tension to such an extent that a phosphate group can very easily detach - the brake for cell growth. Mutated ...
New research presents most extensive pictures ever of an organism's DNA mutation processes
2012-09-18
Biologists and informaticists at Indiana University have produced one of the most extensive pictures ever of mutation processes in the DNA sequence of an organism, elucidating important new evolutionary information about the molecular nature of mutations and how fast those heritable changes occur.
By analyzing the exact genomic changes in the model prokaryote Escherichia coli that had undergone over 200,000 generations of growth in the absence of natural selective pressures, the team led by IU College of Arts and Sciences Department of Biology professor Patricia L. Foster ...
Only half of adults say schools should take action when kids bully with social isolation
2012-09-18
ANN ARBOR, Mich. – U.S. adults repeatedly rate bullying as a major health problem for U.S. children. But a new poll from the University of Michigan shows adults have different views about what bullying behaviors should prompt schools to take action.
The University of Michigan C.S. Mott Children's Hospital National Poll on Children's Health recently asked a nationwide sample of adults what behaviors should be considered bullying and what behaviors should spur school officials to intervene.
The vast majority of adults (95 percent) say schools should take action if a student ...
Shrinking snow depth on Arctic sea ice threatens ringed seal habitat
2012-09-18
As sea ice in the Arctic continues to shrink during this century, more than two thirds of the area with sufficient snow cover for ringed seals to reproduce also will disappear, challenging their survival, scientists report in a new study.
The ringed seal, currently under consideration for threatened species listing, builds caves to rear its young in snow drifts on sea ice. Snow depths must be on average at least 20 centimeters, or 8 inches, to enable drifts deep enough to support the caves.
"It's an absolute condition they need," said Cecilia Bitz, an associate professor ...