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Scottish and American scientists have found a new way to prevent flu infections that could, in theory, be used to fight an epidemic long before a vaccine is ready. The method, successfully tested only in mice thus far, is a nasal spray of engineered proteins that coat the receptors in the nose and throat to which flu viruses attach.
“We think it has potential,” said Dr. Robert G. Webster, a leading flu expert at St. Jude Children’s Research Hospital in Memphis. If one of these viruses “like H5N1 or H7N9 gets away, you could use it in a family or a community.”
Dr. Webster did some of the testing and was a co-author of the study, published on Monday by Proceedings of the National Academy of Sciences.
University of St. Andrews
Beaded HeartIn each of my constructions, surface design is the key component. Czech seed beads adorn objects in colorful patterns, camouflaging their original circumstance, allowing us to see them as pure form without their.
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In dense, urban centers around the world, many people live and work in dim and narrow streets surrounded by tall buildings that block sunlight. And as the global population continues to rise and buildings are jammed closer together, the darkness will only spread.
To alleviate the problem, Egyptian researchers have developed a corrugated, translucent panel that redirects sunlight onto narrow streets and alleyways. The panel is mounted on rooftops and hung over the edge at an angle, where it spreads sunlight onto the street below. The researchers describe their design in a paper published today in Energy Express, a supplement of The Optical Society’s (OSA) open-access journal Optics Express.
"Research has shown that lack of natural lighting can cause severe physiological problems," such as serious mood changes, excessive sleeping, loss of energy and depression, Safwat said.
Sally I. El-Henawy, Mohamed W. N. Mohamed, Islam A. Mashaly, Osama N. Mohamed, Ola Galal, Iman Taha, Khaled Nassar, Amr M. E. Safwat. Illumination of dense urban areas by light redirecting panels. Optics Express, 2014; 22 (S3): A895 DOI: 10.1364/OE.22.00A895
A simulation of the illuminance of an alleyway at noon at two different times of year, autumn (top) and winter (bottom). The new light-directing panel increases the amount of light that reaches the alleyway, as indicated by the higher amounts of red and yellow in the right-hand images (“with panel”) compared to the left-hand images (“without panel”). Credit: Optics Express
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Trauma’s impact comes partly from social factors, such as its influence on how parents interact with their children. But stress also leaves ‘epigenetic marks’ — chemical changes that affect how DNA is expressed without altering its sequence. A study published this week in Nature Neuroscience finds that stress in early life alters the production of small RNAs, called microRNAs, in the sperm of mice (K. Gapp et al. Nature Neurosci. http://dx.doi.org/10.1038/nn.3695; 2014). The mice show depressive behaviours that persist in their progeny, which also show glitches in metabolism.
A number of sperm trying to fertilise an egg.
Breaking Bad Mitochondria
Mechanism helps explain persistence of hepatitis C virus
Researchers at the University of California, San Diego School of Medicine have identified a mechanism that explains why people with the hepatitis C virus get liver disease and why the virus is able to persist in the body for so long.
The hard-to-kill pathogen, which infects an estimated 200 million people worldwide, attacks the liver cells’ energy centers – the mitochondria – dismantling the cell’s innate ability to fight infection. It does this by altering cells mitochondrial dynamics.
The study, published in today’s issue of the Proceedings of the National Academy of Sciences, suggests that mitochondrial operations could be a therapeutic target against hepatitis C, the leading cause of liver transplants and a major cause of liver cancer in the U.S.
“Our study tells us the story of how the hepatitis C virus causes liver disease,” said Aleem Siddiqui, PhD, professor of medicine and senior author. “The virus damages mitochondria in liver cells. Cells recognize the damage and respond to it by recruiting proteins that tell the mitochondria to eliminate the damaged area, but the repair process ends up helping the virus.”
Mitochondria are organelles in a cell that convert energy from food (glucose) into a form of energy that can be used by cells called adenosine triphosphate.
Specifically, the researchers discovered that the virus stimulates the production of a protein (Drp 1) that induces viral-damaged mitochondria to undergo asymmetric fragmentation. This fragmentation (fission) results in the formation of one healthy mitochondrion and one damaged or bad mitochondrion, the latter of which is quickly broken down (catabolized) and dissolved in the cell’s cytoplasm.
Pictured: Mitochondria in hepatitis C-infected cells (bottom row) are self-destructing. The self-annihilation process explains the persistance and virulence of the virus in human liver cells.
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One of the scientists who revealed how plants “do maths” can now reveal how cells take measurements of size. Size is important to cells as it determines when they divide.
In a paper published in eLife, Professor Martin Howard from the John Innes Centre and colleagues from the US, Germany and Singapore discovered that cells measure their surface area using a particular protein, cdr2p. The finding challenges a previous model suggesting that another protein called pom1p senses a cell’s length.
"Many cell types have been shown to reach a size threshold before they commit to cell division and this requires that they somehow monitor their own size," says Professor Martin Howard from the John Innes Centre.
"For the first time we can show how cells sense size and what aspect of size they measure, such as volume, length, mass or surface area."
The scientists found that as cells grow, the concentration of the cdr2p protein grows. The cells use cdr2p to probe the surface area over the whole cell. Their experimental findings contest a previously suggested model.
Fluorescence micrograph showing human cells at various stages of cell division, starting with interphase at the top. During interphase the cell gets bigger and duplicates its DNA. The second cell shows prophase, the stage at which the chromosomes form. The third cell is in metaphase, where all the chromosomes are attached and aligned on the spindle. The fourth cell down shows anaphase, the stage at which the chromosomes separate. The final cell is in telophase, and the newly separated genetic material is encased into two new nuclei.
Credit: Matthew Daniels, Wellcome Images.
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A lot of us know what can happen when we get hungry. We get grumpy, irritable and sometimes nasty. There’s even a name for this phenomenon: “Hangry, which is a combination of the words hungry and angry,” says psychologist from Ohio State University.
Bushman recruited 107 couples to study the relationship between blood sugar levels and anger. He assessed the quality of their relationships and taught them how to measure their blood sugar. Then he sent each volunteer home with something unusual: a voodoo doll and 51 pins.
After three weeks, Bushman and his team assessed the damage done to each doll. Volunteers who had low levels of blood glucose stuck more pins in the voodoo dolls than those who had high levels of blood glucose, Bushman and his team reported Monday in The Proceedings of the National Academy of Sciences.
Volunteers with lower levels of blood sugar stuck more pins in voodoo dolls of their spouses than people with higher levels. Courtesy of Brad Bushman
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What a strange thing!
to be alive
beneath cherry blossoms.
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Killer sponges thrive in the lightless depths of the deep sea. Scientists first discovered that some sponges are carnivorous about 20 years ago. Since then only seven carnivorous species have been found in all of the northeastern Pacific. A new paper authored by MBARI marine biologist Lonny Lundsten and two Canadian researchers describes four new species of carnivorous sponges living on the deep seafloor, from the Pacific Northwest to Baja California.
These animals look like bare twigs or small shrubs covered with tiny hairs. But the hairs consist of tightly packed bundles of microscopic hooks that trap small animals such as shrimp-like amphipods. Once an animal becomes trapped, it takes only a few hours for sponge cells to begin engulfing and digesting it. After several days, all that is left is an empty shell.
Caption: A large group of Asbestopluma monticola sponges grow on top of a dead sponge on Davidson Seamount, off the Central California coast. Credit: © 2006 MBARI
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