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Rescooped by W H Unsell from Biology_Ecology onto WWWBiology |
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The Smithsonian Museum of Natural History is a fabulous resource in Washington D.C., but now this museum available virtually. Teachers can now bring the museums to the classroom with these fantastic Smithsonian virtual tours.
Tags: biogeography, virtual tours, environment, ecology, historical, physical.
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Glowing cockroaches and a destructive fungus make the grade in Arizona State's list of top 10 new species of 2012. Via Michael Miller 
Linda Alexander's curator insight,
June 17, 8:22 PM
Biomimicry scholars need to take a look at some of the new species findings, especially the snake. Delete the scoop?
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The Amazon rainforest, a well-known epicenter of biodiversity, has offered up another trove of riches. The treasure takes the form of 15 newly described bird species. Some are tiny. One has a long, curved bill. Another is super fluffy. All live in the southern Amazon, most of them in an area known as the “arc of deforestation.”
The Arapaçu-de-bico-torto, which loosely translates to crooked-beaked woodcreeper. This bird most closely resembles a Curve-Billed Scythebill (Campylorhamphus procurvoides), said Tom Schulenberg, an expert in neotropical birds and Peruvian species, from the Cornell Lab of Ornithology.
It’s been 140 years since as many new Brazilian bird species were described at one time. In 1871, 40 new species were described by Austrian August von Pelzeln in Zur Ornithologie Brasiliens.
Discovered mostly within the last five years, in southern swaths of forest, many of the birds live near rivers. Eleven can only be found in Brazil; four of the species have also been seen in Peru and Bolivia. Most are Passeriformes, belonging to an order that includes ravens, sparrows, and finches.
They were spotted on various expeditions that included ornithologist Luis Silveira, of the University of São Paulo, and his students, as well as collaborators from three additional institutions. Together, they noticed that these strange new birds didn’t quite fit in.
“Describing new species is not a trivial task,” Silveira said. Many sang different songs, or had different genetic sequences than previously known birds. “We considered a bird as a new species when at least two of the three criteria — plumage, voice, and genetics — were consistently different from some previously known and closely related, already described species.”
Silveira and his colleagues will describe the species in a special volume of the Handbook of Birds of the World, which will be published in early summer. Here, we have photos of seven new species; others have only been illustrated.
Via Dr. Stefan Gruenwald 
Vloasis's curator insight,
June 6, 8:32 AM
What sheds a pall over these discoveries (the largest group in 140 years), is the fact that deforestation helped reveal them. Delete the scoop?
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Suzanne Gildert's talk at Humanity+ @ Caltech ( http://www.humanityplus.org/conferences/ ) about "What do super-intelligences REALLY want?" and will they outsmart mankind during in a singularity event.
Here are the 10 D-wave technology presentation videos - lectures given by Dr. Suzanne Gildert in 2009 Via Dr. Stefan Gruenwald Delete the scoop?
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Translational Bioinformatics: PLOS Computational Biology presents an educational resource for an emerging field http://t.co/ihZkBUzy Delete the scoop?
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A single injection of human neural stem cells produced neuronal regeneration and improvement of function and mobility in rats impaired by an acute spinal cord injury (SCI), an international team led by researchers at the University of California, San Diego School of Medicine reports.
Grafting neural stem cells derived from a human fetal spinal cord to the rats’ spinal injury site produced an array of therapeutic benefits — from less muscle spasticity to new connections between the injected stem cells and surviving host neurons.
Via Ray and Terry's , Dr. Stefan Gruenwald Delete the scoop?
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Scientists from Yale and UCL have identified a new mechanism that regulates VEGFR2 transport in vascular cells, opening new therapeutic opportunities for developing drugs to stimulate or inhibit blood vessel formation.
Arteries form in utero and during development, but can also form in adults when organs become deprived of oxygen — for example, after a heart attack. The organs release a molecular signal called VEGF. Working with mice, the Yale-UCL team discovered that in order for VEGF-driven artery formation to occur, VEGF must bind with two molecules known as VEGFR2 and NRP1, and all three must work as a team.
The researchers examined mice that were lacking a particular part of the NRP1 molecule that transports VEGF and VEGFR2 to a signaling center inside blood vessel walls. They observed that the internal organs of these mice contained poorly constructed arterial branches. Further, the mice where unable to efficiently repair blood vessel blockage through the formation of new arteries.
“We have identified an important new mechanism that regulates VEGFR2 transport in vascular cells,” said corresponding author Michael Simons, professor of medicine and cell biology, and director of the cardiovascular research center at Yale School of Medicine. “This opens new therapeutic opportunities for developing drugs that would either stimulate or inhibit blood vessel formation — important goals in cardiovascular and anti-cancer therapies, respectively.” Via Dr. Stefan Gruenwald 
Biosciencia's curator insight,
May 2, 5:16 AM
Michael Simons, professor of medicine and cell biology, and director of the cardiovascular research center at Yale School of Medicine said "We have identified an important new mechanism that regulates VEGFR2 transport in vascular cells” Delete the scoop?
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FREE CODE for 2 days at codeschool: http://go.codeschool.com/PzsLdA Via Dr. Stefan Gruenwald 
NUMBER 1 FOOD TESTING CERTIFICATION SERVICE INDIA's curator insight,
May 18, 1:03 PM
20,000+ FREE Online Science and Technology Lectures 
Pedeta Deutscher's comment,
May 31, 11:04 PM
Fantastic website with a variety of good resources for students and teachers.
sonia ramos's comment,
June 4, 4:14 PM
Thanks for your comment Pedeta, great prezzi:about you: http://prezi.com/7gdnbgur7glu/introducing-pedeta/ xD
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New research indicates that leaf growth may not be as complicated as it seems. When compared species to species, shorter trees exhibit a greater variety of leaf sizes than taller ones, with the tallest trees all having leaves that measure 10 to 20 centimeters in length.
The scientists published their findings in the journal Physical Review Letters⊃1;. The narrow size range may be simply explained in the inner workings of trees. If this is correct, this could also explain why the tallest trees can only attain about 100 meters.
The team only considered angiosperms like maples and oaks, not gymnosperms, like pines and redwoods. They reviewed data for 1925 species and found that among angiosperms shorter than 30 meters, leaf length varies enormously, from 3 cm all the way up to 60 cm. The range narrows as the trees become taller.
The flow of sap and energy throughout the tree is what explains this. A leaf of an angiosperm produces a sugary sap that flows into a network of cells called the phloem, which transports the sap down to the tree’s trunk and through the roots. While it’s in transit, the tree metabolizes the sugar. The flow is driven by the difference in concentration in the sugars, which generates osmotic pressure.
The scientists modeled a tree as a pair of cylindrical tubes. A short, permeable tube, which represented the phloem in the leaf, was attached to a long, impermeable tube, the phloem in the trunk. Sap diffuses into the leave phloem and travels down into the trunk phloem. The longer the permeable leaf tube is, the more the surface area it has, so the more easily sap can enter. In the trunk phloem, the longer the tube is, the more resistance it offers to flow.
The scientists then considered how the total flow of sap and energy varies with leaf length. If the leaves are big, the resistance from the trunk limits the flow and making the leaves bigger than a certain maximum length yields no additional flow or benefit. On the other hand, if the leaves are very small, their resistance limits the flow. And if the leaf is shorter than a certain minimum length, the sap would flow through the phloem more slowly than it could diffuse through the entire tree.
Trees taller than 100 meters simply could not produce leaves that obey both length limits, setting a limit for tree height. Other scientists think that the uniformity of leaf size amongst the tallest trees could come from the comparable environments and conditions that produce them.
One way to test how the flow speed varies with the height of a tree and the length of its leaves would be to directly measure it in different species of tall trees, but that might require taking an MRI machine into a rain forest canopy. Via Dr. Stefan Gruenwald 
mdashf's curator insight,
May 8, 3:11 AM
why some trees are so tall while others are short? well their leaves size will be affected as well deoending on their heights. Its like very tall men will have proportionate to their height smaller fingers. But shorter men and women will grow fingers in many differet ratio to their height. You lose certain privilege if you are tall. Delete the scoop?
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Elevated levels of nitrogen dioxide pop out over certain shipping lanes in observations made by the Aura satellite between 2005-2012. The signal was the strongest over the northeastern Indian Ocean. Via Seth Dixon, Mark Slusher 
David Collet's curator insight,
February 19, 10:37 PM
The Straits of Malacca show up as a highly affected band - and this from traffic that is not even bound for, or related to, Malaysia. Delete the scoop?
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Biomass as a source for power and heat generation promises to play an important role in the energy mix of the future. Via SustainOurEarth 
Tim Marston's comment,
February 19, 5:00 AM
The sooner we get away from our obsession with fossil fuels the better!
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Xylella fastidiosa is not your ordinary kind of bug. It made it to the list of the most wanted plant pathogenic bacteria in 2012! This is well deserved: X. fastidiosa can infect over a hundred species (grapevine, oleander, citrus, almonds,…), and it causes severe symptoms that can kill the infected plant. TheXylella bacteria colonize the xylem vessels, and by doing so they block the transport of water in the plant. The water-deprived leaves dry and scorch, until finally they drop to the ground.
Check also the video on the glassy-winged sharpshooter leafhopper. Via Kamoun Lab @ TSL 
Hao-Xun Chang's comment,
February 16, 10:11 AM
I love your blog!!! I'm also study plant pathology~ I'll keep following.
Diana Rivera's curator insight,
March 4, 6:08 PM
This type of pathogen can be very dangerous to any grower. The Xylella Fastidiosa can whip out an entire harvest of crops, and some people might not understand how dangerous they can be to society. By taking out feilds of crops they are putting our natural resource in danger. Everyone needs to eat nutricious foods, but these pathogens are threating our health. Delete the scoop?
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Shipworms are marine wood-boring bivalve mollusks (family Teredinidae) that harbor a community of closely related Gammaproteobacteria as intracellular endosymbionts in their gills. These symbionts have been proposed to assist the shipworm host in cellulose digestion and have been shown to play a role in nitrogen fixation. The genome of one strain of Teredinibacter turnerae, the first shipworm symbiont to be cultivated, was sequenced, revealing potential as a rich source of polyketides and nonribosomal peptides. Bioassay-guided fractionation led to the isolation and identification of two macrodioloide polyketides belonging to the tartrolon class. Both compounds were found to possess antibacterial properties, and the major compound was found to inhibit other shipworm symbiont strains and various pathogenic bacteria. The gene cluster responsible for the synthesis of these compounds was identified and characterized, and the ketosynthase domains were analyzed phylogenetically. Reverse-transcription PCR in addition to liquid chromatography and high-resolution mass spectrometry and tandem mass spectrometry revealed the transcription of these genes and the presence of the compounds in the shipworm, suggesting that the gene cluster is expressed in vivo and that the compounds may fulfill a specific function for the shipworm host. This study reports tartrolon polyketides from a shipworm symbiont and unveils the biosynthetic gene cluster of a member of this class of compounds, which might reveal the mechanism by which these bioactive metabolites are biosynthesized.
Sherif I. Elshahawi, Amaro E. Trindade-Silva, Amro Hanora, Andrew W. Han, Malem S. Flores, Vinicius Vizzoni, Carlos G. Schrago, Carlos A. Soares, Gisela P. Concepcion, Dan L. Distel, Eric W. Schmidtf, and Margo G. Haygood PNAS January 22, 2013 vol. 110 no. 4 E295-E304 doi: 10.1073/pnas.1213892110
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Efficiency and precision in plant breeding can be enhanced by using diagnostic DNA-based markers for the selection of superior cultivars. This technique has been applied to many crops, including potatoes. The first generation of diagnostic DNA-based markers useful in potato breeding were enabled by several developments: genetic linkage maps based on DNA polymorphisms, linkage mapping of qualitative and quantitative agronomic traits, cloning and functional analysis of genes for pathogen resistance and genes controlling plant metabolism, and association genetics in collections of tetraploid varieties and advanced breeding clones. Although these have led to significant improvements in potato genetics, the prediction of most, if not all, natural variation in agronomic traits by diagnostic markers ultimately requires the identification of the causal genes and their allelic variants. This objective will be facilitated by new genomic tools, such as genomic resequencing and comparative profiling of the proteome, transcriptome, and metabolome in combination with phenotyping genetic materials relevant for variety development. Via Jean-Pierre Zryd Delete the scoop?
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Discovery of how parasite sticks to blood vessels could lead to new means to combat malaria.
Malaria parasites grow in red blood cells and stick to the endothelial lining of blood vessels through a large family of parasite proteins called PfEMP1. This way, the parasite avoids being carried with the blood to the spleen, where it would otherwise be destroyed. One of the most aggressive forms of malaria parasite binds in brain blood vessels, causing a disease called cerebral malaria.
In 2012, three groups of researchers, including the teams at the University of Copenhagen and Seattle Biomedical Research Institute, showed that a specific type of PfEMP1 protein was responsible for cerebral binding and other severe forms of malaria infection. However, until now, the receptor to which it binds remained unknown, and the next big question was to determine which receptors the infected red blood cells were binding to.
“The first big challenge was to generate a full-length PfEMP1 protein in the laboratory,” says Assistant Professor Louise Turner at the University of Copenhagen. “Next, we utilized a new technology developed by Retrogenix LTD in the United Kingdom to examine which of over 2,500 human proteins this PfEMP1 protein could bind to.” Of the 2,500 proteins screened, a receptor called endothelial protein C (EPCR) was the single solid hit.
“A lot of work then went into confirm this binding in the lab and not least to show that parasites from non-immune children with severe malaria symptoms in Tanzania often bound EPCR,” she continues.
“It was a true eureka moment,” says Assistant Professor Thomas Lavstsen. “Under normal conditions, ECPR plays a crucial role in regulating blood clotting, inflammation, cell death and the permeability of blood vessels. The discovery that parasites bind and interfere with this receptor´s normal function may help us explain why severe symptoms of malaria develop."
Severe malaria symptoms such as cerebral malaria often result in minor blood clots in the brain. One of our body´s responses to malaria infection is to produce inflammatory cytokines, but too much inflammation is dangerous, describes Professor Joseph Smith, from the Seattle Biomedical Research Institute.
“ECPR and a factor in the blood called protein C act as a ‘brake’ on blood coagulation and endothelial cell inflammation and also enhance the viability and integrity of blood vessels, but when the malaria parasites use PfEMP1 to bind EPCR, they may interfere with the normal function of EPCR, and thus the binding can be the catalyst for the violent reaction,” he explains.
“Now that we know the pair of proteins involved, we can begin zooming further in to reveal the molecular details of how malaria parasites grab onto the sides of blood vessels. We want to know exactly which bits of the parasite protein are needed to bind to the receptor in the blood vessel wall. Then, we can aim to design vaccines or drugs to prevent this binding.”
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A new method of manufacturing short, single-stranded DNA molecules can solve many of the problems associated with current production methods. The new method can be of value to development of drugs consisting of DNA fragments and to DNA nanotechnology research.
The novel technique for manufacturing short, single-stranded DNA molecules — or oligonucleotides — has been developed by researchers at Karolinska Institute in Sweden and Harvard University.
Such DNA fragments constitute a basic tool for researchers and play a key part in many fields of science. Many of the recent advances in genetic and molecular biological research and development, such as the ability to quickly scan an organism’s genome, would not have been possible without oligonucleotides.
The new method is versatile and able to solve problems that currently restrict the production of DNA fragments.
“We’ve used enzymatic production methods to create a system that not only improves the quality of the manufactured oligonucleotides but that also makes it possible to scale up production using bacteria in order to produce large amounts of DNA copies cheaply,” says co-developer Björn Högberg at the Swedish Medical Nanoscience Center, part of the Department of Neuroscience at Karolinska Institutet in Sweden.
The process of bioproduction, whereby bacteria are used to copy DNA sequences, enables the manufacture of large amounts of DNA copies at a low cost. Unlike current methods of synthesising oligonucleotides, where the number of errors increases with the length of the sequence, this new method according to the developers also works well for long oligonucleotides of several hundred nitrogenous bases.
The DNA molecules are first formed as a long string of single-stranded DNA in which the sequence of interest is repeated several times. The long strand forms tiny regions called hairpins, where the strand folds back on itself. These hairpins can then be cut up by enzymes, which serve as a molecular-biological pair of scissors that cuts the DNA at selected sites. Several different oligonucleotides can thus be produced at the same time in a perfectly balanced combination, which is important if they are to be crystallised or used therapeutically.
“Oligonucleotide-based drugs are already available, and it’s very possible that our method could be used to produce purer and cheaper versions of these drugs,” says Dr Björn Högberg. Via Dr. Stefan Gruenwald 
CineversityTV's curator insight,
June 7, 12:26 PM
even science has its fools who open Pandora's box even further. Delete the scoop?
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Rover Finds New Evidence That Ancient Mars Was Habitable and Had Neutral-pH Water Flowing at Surface
NASA's Mars rover Opportunity has made perhaps the biggest discovery of its nearly 10-year career, finding evidence that life may have been able to get a foothold on the Red Planet long ago.
The Opportunity rover spotted clay minerals in an ancient rock on the rim of Mars' Endeavour Crater, suggesting that benign, neutral-pH water once flowed through the area, scientists said.
"This is water you could drink," Opportunity principal investigator Steve Squyres of Cornell University told reporters today (June 7), explaining why the rock, dubbed "Esperance," stands out from other water-soaked stones the rover has studied.
The golf cart-size Opportunity and its twin, Spirit, landed on the Red Planet in January 2004 on three-month missions to search for signs of past water activity. The robotic explorers found plenty of such evidence (much of it indicating extremely acidic water, however), then just kept rolling along.
Spirit stopped communicating with Earth in 2010 and was declared dead a year later, but Opportunity is still going strong. In August 2011, the six-wheeled robot arrived at the rim of the 14-mile-wide Endeavour Crater, which it has been investigating ever since.
Opportunity has seen signs of clays in Endeavour rocks before, but in nowhere near the concentrations observed in Esperance, researchers said. Overall, Esperance provides strong evidence that ancient Mars was habitable.
"The fundamental conditions that we believe to be necessary for life were met here," Squyres said. The neutral-pH water that generated the clays probably flowed through the region during the first billion years of Martian history, he added, stressing that it's nearly impossible to pin down the absolute ages of Red Planet rocks without bringing them back to Earth.
Opportunity's latest discovery fits well with one made recently on the other side of the planet by the rover's bigger, younger cousin Curiosity, which found strong evidence that its landing site could have supported microbial life in the ancient past. Via Dr. Stefan Gruenwald
Vloasis's curator insight,
June 9, 10:14 PM
Also cool and of note: Opportunity is about to break the record for distance traveled on another world. Delete the scoop?
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A recent infographic lists Sustainable Future, Green Homes as one of the top 100 green blogs to follow in 2013. We're number 73. I have no idea what the order means. I've gotten through no. 40 look... Via Linda Alexander
Linda Alexander's curator insight,
May 25, 11:35 AM
A mixed bag of green blogs, but a great resource list to keep in a folder! Delete the scoop?
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Computer chips and silicon micromachines are ready for your body. It’s time to decide how you’ll take them: implantable, ingestible, or intimate contact. Every flavor now exists. Some have FDA approval and some are seeking it. Others are moving quickly out of the research lab stage. With the round one Qualcomm Tricorder X-Prize entries due in one year, we’re soon to see a heavy dose of sensors tied to the mobile wireless health revolution.
With these sensors comes a heavy dose of information about your health, data about what medication you are taking and when you took it. The sensors are available to protect your health, but choosing how to use them and how to protect the privacy of your data will be a matter of personal responsibility.
Via Ray and Terry's , Dr. Stefan Gruenwald Delete the scoop?
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Scientists had known that cicada wings are super-water-repellent, or super-hydrophobic. This is different from a great many substances that are simply water-repellent, or hydrophobic — for instance, oil and water famously do not mix. But a number of surfaces such as lotus leaves can make themselves even more water-repellent by covering themselves with microscopic bumps, so water drops can float on top much as mystics can lie on beds of nails. For example, cicada wings are covered in rows of waxy cones about 200 nanometers or billionths of a meter high. In comparison, the average human hair is roughly 100 microns or millionths of a meter wide.
Mechanical engineer Chuan-Hua Chen at Duke University in Durham, N.C., and his colleagues were investigating a number of natural and artificial super-hydrophobic surfaces when they noticed drops of water at times rapidly disappeared. They were mystified by this behavior for years until they made observations from a different angle — they used a high-speed video camera to watch the droplets from the side of these materials instead of from above. "That's when we saw them jumping upward," Chen recalled. The scientists found that when these surfaces are exposed to water vapor, dew can condense on them. When growing droplets fused together, the merged drop then leapt off the super-water-repellant surfaces. These drops, each up to a few microns to a few hundred microns wide, can jump up to a few millimeters in the air. "We've since found this happens on almost all normal super-hydrophobic surfaces," Chen said. "If you take a lotus leaf or any of the many other super-water-repellant surfaces out there and you let it cool in your freezer and then take it out, as humidity in the air condenses on it, you can see with your bare eyes that water drops will jump in the air."
When small water droplets combine on super-water-repellent surfaces, a single bigger drop results that has less surface area than its original parts. As such, energy that is no longer needed to flatten that water across the surface the smaller droplets once occupied gets released, popping the drop upward, Chen explained. "These findings show that super-hydrophobic surfaces don't need water driven by gravity to take contaminants away — jumping droplets can do so," Chen said. "This is a great piece of work that highlights a mechanism that has not been conventionally considered for self-cleaning," said mechanical engineer Evelyn Wang at the Massachusetts Institute of Technology, who did not take part in this research. Via Dr. Stefan Gruenwald Delete the scoop?
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As the world is transfixed by a new H7N9 bird flu virus spreading through China, a study reminds us that a different avian influenza — H5N1 — still poses a pandemic threat.
A team of scientists in China has created hybrid viruses by mixing genes from H5N1 and the H1N1 strain behind the 2009 swine flu pandemic, and showed that some of the hybrids can spread through the air between guinea pigs.
Flu hybrids can arise naturally when two viral strains infect the same cell and exchange genes. This process, known as reassortment, produced the strains responsible for at least three past flu pandemics, including the one in 2009.
There is no evidence that H5N1 and H1N1 have reassorted naturally yet, but they have many opportunities to do so. The viruses overlap both in their geographical range and in the species they infect, and although H5N1 tends mostly to swap genes in its own lineage, the pandemic H1N1 strain seems to be particularly prone to reassortment.
“If these mammalian-transmissible H5N1 viruses are generated in nature, a pandemic will be highly likely,” says Hualan Chen, a virologist at the Harbin Veterinary Research Institute of the Chinese Academy of Sciences, who led the study.
“It's remarkable work and clearly shows how the continued circulation of H5N1 strains in Asia and Egypt continues to pose a very real threat for human and animal health,” says Jeremy Farrar, director of the Oxford University Clinical Research Unit in Ho Chi Minh City, Vietnam.
Chen's results are likely to reignite the controversy that plagued the flu community last year, when two groups found that H5N1 could go airborne if it carried certain mutations in a gene that produced a protein called haemagglutinin (HA). Following heated debate over biosecurity issues raised by the work, the flu community instigated a voluntary year-long moratorium on research that would produce further transmissible strains. Chen’s experiments were all finished before the hiatus came into effect, but more work of this nature can be expected now that the moratorium has been lifted.
“I do believe such research is critical to our understanding of influenza,” says Farrar. “But such work, anywhere in the world, needs to be tightly regulated and conducted in the most secure facilities, which are registered and certified to a common international standard.”
Virologists have created H5N1 reassortants before. One study found that H5N1 did not produce transmissible hybrids when it reassorts with a flu strain called H3N2. But in 2011, Stacey Schultz-Cherry, a virologist at St. Jude Children's Research Hospital in Memphis, Tennessee, showed that pandemic H1N1 becomes more virulent if it carries the HA gene from H5N1.
Chen’s team mixed and matched seven gene segments from H5N1 and H1N1 in every possible combination, to create 127 reassortant viruses, all with H5N1’s HA gene. Some of these hybrids could spread through the air between guinea pigs in adjacent cages, as long as they carried either or both of two genes from H1N1 called PA and NS. Two further genes from H1N1, NA and M, promoted airborne transmission to a lesser extent, and another, the NP gene, did so in combination with PA. Via Dr. Stefan Gruenwald Delete the scoop?
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UCSF scientists controlled seizures in epileptic mice with a one-time transplantation of medial ganglionic eminence (MGE) cells, which inhibit signaling in overactive nerve circuits, into the hippocampus, a brain region associated with seizures, as well as with learning and memory. Other researchers had previously used different cell types in rodent cell transplantation experiments and failed to stop seizures.
Cell therapy has become an active focus of epilepsy research, in part because current medications, even when effective, only control symptoms and not underlying causes of the disease, according to Scott C. Baraban, PhD, who holds the William K. Bowes Jr. Endowed Chair in Neuroscience Research at UCSF and led the new study. In many types of epilepsy, he said, current drugs have no therapeutic value at all.
"Our results are an encouraging step toward using inhibitory neurons for cell transplantation in adults with severe forms of epilepsy," Baraban said. "This procedure offers the possibility of controlling seizures and rescuing cognitive deficits in these patients."
In the UCSF study, the transplanted inhibitory cells quenched this synchronous, nerve-signaling firestorm, eliminating seizures in half of the treated mice and dramatically reducing the number of spontaneous seizures in the rest. Robert Hunt, PhD, a postdoctoral fellow in the Baraban lab, guided many of the key experiments.
he mouse model of disease that Baraban's lab team worked with is meant to resemble a severe and typically drug-resistant form of human epilepsy called mesial temporal lobe epilepsy, in which seizures are thought to arise in the hippocampus. In contrast to transplants into the hippocampus, transplants into the amygdala, a brain region involved in memory and emotion, failed to halt seizure activity in this same mouse model, the researcher found.
Temporal lobe epilepsy often develops in adolescence, in some cases long after a seizure episode triggered during early childhood by a high fever. A similar condition in mice can be induced with a chemical exposure, and in addition to seizures, this mouse model shares other pathological features with the human condition, such as loss of cells in the hippocampus, behavioral alterations and impaired problem solving.
Via Dr. Stefan Gruenwald
Biosciencia's curator insight,
May 6, 6:38 AM
Cell therapy has become an active focus of epilepsy research, in part because current medications, even when effective, only control symptoms and not underlying causes of the disease. Delete the scoop?
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Eye color is much more complicated than is usually taught in high school (or presented in The Tech’s eye color calculator). There we learn that two genes influence eye color. One gene comes in two versions, brown (B) and blue (b). The other gene comes in green (G) and blue (b). All eye color and inheritance was thought to be explained by this simple model. Except of course for the fact that it is obviously incomplete.
The model cannot, for example, explain how blue eyed parents can have a brown eyed child. Yet this can and does happen (although it isn’t common). New research shows that the first gene is actually two separate genes, OCA2 and HERC2. In other words, there are two ways to end up with blue eyes. Normally this wouldn’t be enough to explain how blue eyed parents can have a brown eyed child. Because of how eye color works (see below), if one gene can cause brown eyes, it would dominate over another that causes blue. In fact, that is what happens with green eyes in the older model. The brown gene dominates over the green one resulting in brown eyes.
The key is that if someone makes a lot of pigment in the front part of their eye, they have brown eyes. And if they make none there, they have blue. Part of the pigment making process involves OCA2 and HERC2. A working HERC2 is needed to turn on OCA2 and OCA2 helps to actually get the pigment made. They need each other to make pigment.
So someone with only broken HERC2 genes will have blue eyes no matter what OCA2 says. This is because the working OCA2 can't be turned on so no pigment gets made.
And the opposite is true as well. Someone with broken OCA2 genes will have blue eyes no matter what the HERC2 genes are. Turning on a broken pigment making gene still gives you no pigment. You need a working HERC2 and a working OCA2 to have brown eyes.
Because the two genes depend on each other, it is possible for someone to actually be a carrier of a dominant trait like brown eyes. And if two blue eyed parents are carriers, then they can have a brown eyed child. Via Dr. Stefan Gruenwald Delete the scoop?
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By Douglas MainLiveScience Via Colin Zylka 
Colin Zylka's curator insight,
February 12, 7:32 PM
This is good news, but still more work needs to be done to protect our precious marine resources. Delete the scoop?
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You might expect dung beetles to keep their 'noses to the ground,' but they are actually incredibly attuned to the sky.
While birds and humans are known to navigate by the stars, the discovery is the first convincing evidence for such abilities in insects, the researchers say. It is also the first known example of any animal getting around by the Milky Way as opposed to the stars. "Even on clear, moonless nights, many dung beetles still manage to orientate along straight paths," said Marie Dacke of Lund University in Sweden. "This led us to suspect that the beetles exploit the starry sky for orientation—a feat that had, to our knowledge, never before been demonstrated in an insect." Dacke and her colleagues found that dung beetles do transport their dung balls along straight paths under a starlit sky but lose the ability under overcast conditions. In a planetarium, the beetles stayed on track equally well under a full starlit sky and one showing only the diffuse streak of the Milky Way. Via Dr. Stefan Gruenwald 
Angel Gavin's curator insight,
January 25, 1:57 AM
A little bit off-topic but amazing anyway. Some insects are able to navigate by the stars!
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An unusual event playing out high in the atmosphere above the Arctic Circle is setting the stage for what could be weeks upon weeks of frigid cold across wide swaths of the U.S.
When the sudden stratospheric warming event began in early January, that signaled to weather forecasters that a cool down was more likely to occur by the end of the month, since it usually takes many days for developments in the stratosphere to affect weather in the troposphere, and vice versa. As the polar stratosphere warms, high pressure builds over the Arctic, causing the polar jet stream to weaken. At the same time, the midlatitude jet stream strengthens, while also becoming wavier, with deeper troughs and ridges corresponding to more intense storms and high pressure areas. In fact, sudden stratospheric warming events even make so-called “blocked” weather patterns more likely to occur, which tilts the odds in favor of the development of winter storms in the U.S. and Europe.
The graph shows the evolution of the stratospheric warming event. The contours show absolute heights and the shading are height anomalies in the middle stratosphere, or about 16 miles above the surface. The height anomalies are a good proxy for temperature anomalies in the stratosphere with red representing high heights or warm temperatures and blue low heights or cold temperatures. You can see at the beginning of the loop a cohesive polar vortex along the coast of Northern Eurasia and then this area of higher heights or warm temperaturs rush poleward from Siberia into the polar vortex splitting it into two pieces, one over Eurasia and one over North America. The dramatic rise in heights or temperatures over the Pole is the sudden stratospheric warming. The result is that pieces of the polar vortex move equatorward and with it the associated cold temperatures. Usually something similar occurs in the troposphere in the ensuing weeks. Via Dr. Stefan Gruenwald Delete the scoop?
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