Tag Archives: pathway

Elusive leptin

Researchers find first evidence of fat-regulating hormone in avian species

Since leptin was discovered 20 years ago, more than 115,000 papers have been published on this protein in humans, and another 5,000 have appeared on leptin in mice.

Leptin’s popularity is not surprising, as the hormone is the principal marker for the development of morbid obesity in humans. Leptin and its receptor play critical roles in the control of food intake and energy expenditure, thereby affecting body weight, abdominal fatness, thermogenesis, insulin sensitivity, and lipid metabolism. (more…)

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Solving an Evolutionary Puzzle

New Bedford Harbor pollution prompts PCB-resistance in Atlantic killifish

For four decades, waste from nearby manufacturing plants flowed into the waters of New Bedford Harbor—an 18,000-acre estuary and busy seaport. The harbor, which is contaminated with polychlorinated biphenyls (PCBs) and heavy metals, is one of the EPA’s largest Superfund cleanup sites.

It’s also the site of an evolutionary puzzle that researchers at Woods Hole Oceanographic Institution (WHOI) and their colleagues have been working to solve. (more…)

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Zebrafish help decode link between calcium deficiency and colon cancer

ANN ARBOR — A tiny, transparent fish embryo and a string of surprises led scientists to a deeper understanding of the perplexing link between low calcium and colon cancer.

By studying zebrafish embryo skin, University of Michigan researchers decoded cell messages underlying abnormal colonic cell growth of the kind that can lead to tumors and colon cancer in calcium deficient individuals. They have also tested this new mechanism in human colon cancer cells. (more…)

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How living cells solved a needle in a haystack problem to generate electrical signals

Scientists have figured out how calcium channels – the infinitesimal cell membrane pores that generate electrical signals by gating a charged-particle influx – have solved a “needle in a haystack” problem.

The solution to the longstanding riddle is reported in the Nov. 24 advanced online edition of Nature by UW and Howard Hughes Medical Institute investigators. Dr. Ning Zheng, a noted X-ray crystallographer, and Dr. William Catterall, a pioneer in ion channel research, were the senior researchers, and Dr. Lin Tang and Dr. Tamer Gamal El-Din headed the project. (more…)

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Face to Face

Research finds infants classify faces by gender, race

Long before babies can talk — even before they can sit up on their own — they are mentally forming categories for objects and animals in a way that, for example, sets apart squares from triangles and cats from dogs, psychologists say.

Now, research conducted by the University of Delaware’s Paul Quinn, professor of psychology, and others indicates that babies as young as 3 months are also classifying faces by race and gender, showing a visual preference for the category they see most often in their daily lives, and that by 9 months they have difficulty recognizing the faces of people from less-familiar races. (more…)

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Rust Never Sleeps

Berkeley Lab-led Observations of Electron Hopping in Iron Oxide Hold Consequences for Environment and Energy

Rust – iron oxide – is a poor conductor of electricity, which is why an electronic device with a rusted battery usually won’t work. Despite this poor conductivity, an electron transferred to a particle of rust will use thermal energy to continually move or “hop” from one atom of iron to the next. Electron mobility in iron oxide can hold huge significance for a broad range of environment- and energy-related reactions, including reactions pertaining to uranium in groundwater and reactions pertaining to low-cost solar energy devices. Predicting the impact of electron-hopping on iron oxide reactions has been problematic in the past, but now, for the first time, a multi-institutional team of researchers, led by scientists at the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have directly observed what happens to electrons after they have been transferred to an iron oxide particle. (more…)

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New Study by WHOI Scientists Provides Baseline Measurements of Carbon in Arctic Ocean

Scientists from the Woods Hole Oceanographic Institution (WHOI) have conducted a new study to measure levels of carbon at various depths in the Arctic Ocean. The study, recently published in the journal Biogeosciences, provides data that will help researchers better understand the Arctic Ocean’s carbon cycle—the pathway through which carbon enters and is used by the marine ecosystem. It will also offer an important point of reference for determining how those levels of carbon change over time, and how the ecosystem responds to rising global temperatures.

“Carbon is the currency of life. Where carbon is coming from, which organisms are using it, how they’re giving off carbon themselves—these things say a lot about how an ocean ecosystem works,” says David Griffith, the lead author on the study. “If warming temperatures perturb the Arctic Ocean, the way that carbon cycles through that system may change.” (more…)

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