Category Archives: Science

‘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…)

West Nile Virus More Prevalent in Low-income Neighborhoods, Study Finds

By Guest PostNovember 16, 2010Health, Sciencebird populations, coma, convulsions, disorientation, economic conditions, henri thomassen, low income neighborhoods, mosquito transmitted disease, mosquitoe, muscle, neck stiffness, North America, orange county, ryan harrigan, thomas smith, united states, west nile virus

Image credit: University of California

Low-income neighborhoods appear to be the most susceptible to West Nile virus, a mosquito-transmitted disease that is linked to more than 1,000 deaths since in the United States since 1999, according to new UCLA-lead research.

Using data on infected humans and mosquitoes from the West Nile virus hotspot of Orange County, Calif., from 2005-08, scientists found that per-capita income and other economic conditions were the single greatest predictor of occurrence, explaining 85-95 percent of the variation. While economic conditions have previously been linked to disease, the study is the first to use a rigorous statistical model. (more…)

Vaccine for Urinary Tract Infections is One Step Closer

By Guest PostNovember 14, 2010Health, Scienceantibiotic, bacteria, bacteria genes, common treatments, ecoli, ecoli bacteria, erin c hagan, fluoroquinolones, gary j faerber, harry l t mobley, resistance, urinary tract infections, urology, utis, women

*Study sheds light on what E. coli genes are doing inside the body during infection*

E. coli bacteria. Image credit: Amy Simms, Ph.D

ANN ARBOR, Mich. — Urinary tract infections are a painful, recurring problem for millions of women. They are also getting more dangerous as bacteria develop resistance to the most common treatments.

Scientists from the University of Michigan have moved one step closer to a vaccine that could prevent a majority of urinary tract infections, which are caused by E. coli bacteria. Using a genetic technique rarely used to look at infections in human hosts, the researchers studied how the E. coli bacteria operate and discovered key differences between how the bacteria’s genes behave in women and how they behave in mice used in experiments.

Their findings, published online Nov. 11 in PLoS Pathogens, could lead to developments that would save billions in health care costs and millions of doctors’ visits and hospitalizations from urinary tract infections each year. (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 commentsScienceaging, bradley olwin, cell transplant, chronic, degenerative muscle diseases, green fluorescent protein, leg muscles, mice, muscle function, muscle stem cells, myofibers, satellite cells, stem cells, transplant, ultraviolet light, university of colorado at boulder

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.

The experiments showed that when young host mice with limb muscle injuries were injected with muscle stem cells from young donor mice, the cells not only repaired the injury within days, they caused the treated muscle to double in mass and sustain itself through the lifetime of the transplanted mice. “This was a very exciting and unexpected result,” said Professor Bradley Olwin of CU-Boulder’s molecular, cellular and developmental biology department, the study’s corresponding author. (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, 2010Scienceastronomy, carbon dioxide, co2 gas, comet, comet tempel 1, cometary nucleus, deep impact spacecraft, digital color cameras, dry ice, epoxy mission, gas, hartley 2, infrared spectrometer, jessica sunshine, jet fuel, lori feaga, michael a'hearn, nucleus, particles, particles of dust, solar system, telescope, tempel 1, tony farnham, university of maryland, water vapor

*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-ledEPOXI 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.

“Previously it was thought that water vapor from water ice was the propulsive force behind jets of material coming off of the body, or nucleus, of the comet,” said University of Maryland Astronomy Professor Jessica Sunshine, who is deputy principal investigator for the EPOXI mission. “We now have unambiguous evidence that solar heating of subsurface frozen carbon dioxide (dry ice), directly to a gas, a process known as sublimation, is powering the many jets of material coming from the comet. This is a finding that only could have been made by traveling to a comet, because ground based telescopes can’t detect CO₂ and current space telescopes aren’t tuned to look for this gas,” Sunshine said. (more…)

UCLA Uses Hybrid, Precision Heart Procedures to Help Stop Deadly Arrhythmias

By Guest PostNovember 9, 20103 commentsHealth, Scienceabnormal rhythms, arrhythmia, cardiologists, catheter ablation, electrical heart mapping systems, heart, high risk patients, hybrid cardiac procedures, kalyanam shivkumar, lower chambers, ventricular arrhythmias, ventricular tachycardia, yoav michowitz

Hybrid Cardiac Procedure. Schematic of the heart showing the minimally-invasive approaches to allow access to the surface of the heart (the blue and red areas) during this hybrid cardiac procedure. Image credit: University of California

New techniques now being used at UCLA allow doctors to more precisely target certain areas of the heart to stop ventricular arrhythmias — serious abnormal rhythms in the heart’s lower chambers — in high-risk patients.

Generally, arrhythmias can be controlled by medications, and sometimes defibrillators. But a potentially life-threatening, recurrent arrhythmia known as a ventricular tachycardia, which originates in one of the heart’s two ventricles, can produce a fast heart beat that requires other interventions, such as catheter ablation, in which the precise focus area of the arrhythmia must be controlled.

Cardiologists will often use catheter ablation once medications and other therapies have failed. The procedure involves the insertion of a tiny, metal-tipped catheter through a vein in the groin or neck to reach the inside of the heart. Prior to the procedure, electrical tests are conducted on the heart to identify and map the exact site of the arrhythmia’s origin. (more…)