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‘Novel Ocean-Crust Mechanism Could Affect World’s Carbon Budget’

By Guest PostNovember 17, 2010Environment, Scienceadam soule, atmosphere, baja peninsula, bathymetry, carbon, climate, CO2, crust, daniel lizarralde, earth, gas, giora proskurowski, greenhouse gases, guaymas basin, gulf of california, hydrothermal vent, jeff s seewald, methane, molten magma, north guaymas, ocean, red sea, s adam soule, seafloor, tectonic plates, undersea ridges, volcanic rocks

The Earth is constantly manufacturing new crust, spewing molten magma up along undersea ridges at the boundaries of tectonic plates. The process is critical to the planet’s metabolism, including the cycle of underwater life and the delicate balance of carbon in the ocean and atmosphere.

Now, scientists at the Woods Hole Oceanographic Institution (WHOI) have observed ocean crust forming in an entirely unexpected way—one that may influence those cycles of life and carbon and, in turn, affect the much-discussed future of the world’s climate.

Working at the Guaymas basin in the Gulf of California, WHOI scientists confirmed what they suspected from brief glimpses of the area during previous missions: The inner Earth is injecting swaths of magma called sills as far as 50 kilometers away from the plate boundary, on each side of the ridge —nearly 10 times farther from such an active ocean ridge than had been observed before. (more…)

UCLA Researchers Identify Molecular Program for Brain Repair Following Stroke

By Guest PostNovember 13, 20101 commentHealth, Scienceadult brain, atrx, axons, brain, brain stroke, carmichael, cells, DNA, drug, gene, giovanni coppola, healing process, molecular cascade, mouse, neurons, peri infarct tissue, s thomas carmichael, stroke

Mouse Stroke. An MRI of a mouse brain after stroke. The mouse section has been stained to show cell bodies. Image credit: University of California

A stroke wreaks havoc in the brain, destroying its cells and the connections between them. Depending on its severity and location, a stroke can impact someone’s life forever, affecting motor activity, speech, memories, and more.

The brain makes an attempt to rally by itself, sprouting a few new connections, called axons, that reconnect some areas of the brain. But the process is weak, and the older the brain, the poorer the repair. Still, understanding the cascade of molecular events that drive even this weak attempt could lead to developing drugs to boost and accelerate this healing process.

Now researchers at UCLA have achieved a promising first step. Reporting in the current online edition of the journal Nature Neuroscience, senior author Dr. S. Thomas Carmichael, a UCLA associate professor of neurology, and colleagues have, for the first time, identified in the mouse the molecular cascade that drives the process of reconnection or sprouting in the adult brain after stroke. (more…)

Stem Cell Transplants in Mice Produce Lifelong Enhancement of Muscle Mass

By Guest PostNovember 13, 20102 commentsSciencemuscle mass regeneration, muscle regenerative process, muscle stem cells, stem cell therapy, stem cell transplants, transplanted young cells

A University of Colorado at Boulder-led study shows that specific types of stem cells transplanted into the leg muscles of mice prevented the loss of muscle function and mass that normally occurs with aging, a finding with potential uses in treating humans with chronic, degenerative muscle diseases. (more…)

Depression Linked to Altered Activity of Circadian Rhythm Gene

By Guest PostNovember 12, 2010Health, Sciencebehavioral cycle, circadian rhythm, clock gene, dementia, depression, humans, insomnia symptoms, james connors, jean philippe gouin, messenger rna, molecular level, mrna

COLUMBUS, Ohio – Depression appears to be associated with a molecular-level disturbance in the body’s 24-hour clock, new research suggests.

Scientists examined genes that regulate circadian rhythm in people with and without a history of depression. As a group, those with a history of depression had a higher level of activity of the so-called Clock gene, which has a role in regulating circadian rhythm, than did people with no mood disorders.

Higher expression levels of this gene suggest something is amiss in the body’s 24-hour biological and behavioral cycle, which could affect sleep patterns and other physiological functions governed by circadian rhythm. Sleep disturbance is a common symptom of depression. (more…)

Primordial Dry Ice Fuels Comet Jets

By Guest PostNovember 10, 2010Sciencecomet hartley, comet jets, dry ice, frozen carbon dioxide, super volatiles

Initial science results on comet released from University of Maryland, much more to come UMD scientists say

Jets Galore. This enhanced image, one of the closest taken of comet Hartley 2. Image credit: University of Maryland

COLLEGE PARK, Md. – One of the biggest comet findings coming out of the amazing images and data taken by the University of Maryland-led EPOXI mission as it zipped past comet Hartley 2 last week is that dry ice is the ‘jet’ fuel for this comet and perhaps many others.

Images from the flyby show spectacular jets of gas and particles bursting from many distinct spots on the surface of the comet. This is the first time images of a comet have been sharp enough to allow scientists to link jets of dust and gas with specific surface features. Analysis of the spectral signatures of the materials coming from the jets shows primarily CO₂ gas (carbon dioxide) and particles of dust and ice. (more…)

Low Blood Levels of Vitamin D Linked to Chubbier Kids, Faster Weight Gain

By Guest PostNovember 8, 2010Health, Scienceanthropometric indicators, dartmouth medical school, eduardo villamor, national university of Colombia, subscapular-to-triceps, subtropical areas

ANN ARBOR, Mich.—Kids who are deficient in vitamin D accumulated fat around the waist and gained weight more rapidly than kids who got enough vitamin D, a new University of Michigan study suggests.

Vitamin D, which is primarily provided to the body by the sun, has been a hot topic in the U.S. lately. The federal standards for vitamin D intake have come under fire by public health professionals as being much too low, and disagreement continues over the proper amount of vitamin D necessary for optimal health. (more…)

Study Shows Extreme Form of Pregnancy-Related Morning Sickness Could be Genetic

By Guest PostNovember 8, 2010Health, Sciencegenetic component, grandmothers, gynecology, hg, hyperemesis gravidarum, marlena fejzo, morning sickness, mothers, nausea, pregnancy, pregnant women, sisters, vomiting

*Pregnant women whose sisters had condition are 17 times more likely to have it*

Approximately 60,000 pregnant women are hospitalized each year due to hyperemesis gravidarum (HG), an extreme form of nausea and vomiting that endangers their lives and often forces them to reluctantly terminate their pregnancies.

And for women with sisters, mothers and grandmothers on either side of the family who have experienced extreme morning sickness during pregnancy, the risk of HG may be heightened, according to a new study led by researchers from UCLA and the University of Southern California. (more…)

New 3-D Model of RNA ‘Core Domain’ of Enzyme Telomerase May Offer Clues to Cancer, Aging

By Guest PostNovember 6, 2010Health, Scienceaging, cancer, cells, chromosomes, DNA, dna damage, enzyme, helical extension, juli feigon, medicine, nmr, nobel prize, nuclear magnetic resonance, physiology, proteins, pseudoknot, qi zhang, rna, spectroscopy, telomerase, telomeres, virus

A model representation of telomerase's RNA "core domain," determined by Juli Feigon, Qi Zhang and colleagues in Feigon's UCLA laboratory. Image credit: Juli Feigon, UCLA Chemistry and Biochemistry/PNAS

Telomerase is an enzyme that maintains the DNA at the ends of our chromosomes, known as telomeres. In the absence of telomerase activity, every time our cells divide, our telomeres get shorter. This is part of the natural aging process, as most cells in the human body do not have much active telomerase. Eventually, these DNA-containing telomeres, which act as protective caps at the ends of chromosomes, become so short that the cells die.

But in some cells, such as cancer cells, telomerase, which is composed of RNA and proteins, is highly active and adds telomere DNA, preventing telomere shortening and extending the life of the cell.

UCLA biochemists have now produced a three-dimensional structural model of the RNA “core domain” of the telomerase enzyme. Because telomerase plays a surprisingly important role in cancer and aging, understanding its structure could lead to new approaches for treating disease, the researchers say. (more…)

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