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POPSThe Coming Death Shortage "Why the longevity boom will make us sorry to be alive" a must read. Though I fail to agree with many of the premises of this article, the critical views it presents are important and the issues need be taken into consideration seriously
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POPSViruses can catch colds, says study that redefines life itself Prof La Scola and his colleagues were surprised to spot a smaller type of virus attached to the virus-making factory inside infected cells. The new virus - Sputnik - was unable to infect cells by itself but seemed to hijack the larger to achieve its infectious aims. By regulating the growth and death of plankton, giant viruses - and satellite viruses such as Sputnik - could be a major influence on ocean nutrient cycles and climate. "These viruses could be major players in global systems," Nature is told by Prof Curtis Suttle, an expert in marine viruses at the University of British Columbia in Vancouver.
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POPSScientists Find a Second Code Hidden in DNA How cool is this? A secondary DNA meta-code has been discovered superimposed on top of the same "genetic code" whose transcription it influences! (Douglas Hofstadter would have had a field day with this!) Highly efficient from an information science point of view. There are so many wonders to be discovered within our very selves!
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POPS'Supermice' who can resist cancer and age almost half as fast as normal In the latest study, published in the journal Cell, the scientists solved that problem by changing the genes of the mice first to make them resistant to the disease. The researchers found that mice which had been created in this way had better muscle in old age, healthier skin tissue and fewer digestion problems. "By simultaneously increasing the amounts of telomerase and the resistance to cancer we are able to delay ageing in mice and also to extend their life span by 40 per cent," said Maria A. Blasco, from the Spanish National Cancer Research Centre (CNIO), who carried out the study with colleagues from Valencia University. "These mice get to live for as long as the eldest mice in records of the same kind. "If we were to parallel it to humans, then it would mean reaching 120 years of age and also to start ageing much later in life."
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POPSBacteria provide horsepower for tiny motor When bacteria crawl clockwise in the circular groove underlying this motor, they brush past the tabs that support the motor's star-shaped rotor. Molecular bonds between the microbes and a coating on the rotor tug the device around.
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POPSDon't Know Much Biology This attitude has enormous political—and educational—implications. What happens if scientific truth conflicts with a politician's "spiritual truth"? This is not a theoretical problem, but a real one, as we see in debates about stem-cell research, abortion, genetic engineering, and global warming. Ignorance about evolution may be widespread, but it's not nearly as dangerous as dogmatic certainty about the real world based on faith alone.
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POPSThe Secret Of Fast Complex Brain Restructuring Up to now, it had been assumed that nerve cells can only exchange information via the synapses which are special contact points. However, synapses require up to two days to become fully functional - a waste of time and energy if the contact is to be broken down again. The brain could take almost 1000 years to develop if a synapse had to mature at each cell contact. It appears that nerve cells can also obtain information about their neighbours even without a synapse. Neurobiologists Christian Lohmann and Tobias Bonhoeffer from the Max Planck Institute for Neurobiology have now explained how they do that. The secret to how the information is exchanged: local calcium signals very quickly transmit all the necessary information to the cell. A synapse only actually develops when the cell and the contact point prove to be suitable candidates for long-term contact.
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POPSDon't Stress! Bacterial Cell's 'Crisis Command Center' Revealed If a bacteria cell finds itself in a dangerous situation - for example, if the temperature or saltiness of the bacteria's environment reach dangerous levels which threaten the survival of the bacteria -a warning signal from the cell's surface is transmitted into the cell. Using cutting edge electron microscopy imaging techniques the authors of the new research observed that the stressosomes receive this warning signal, and in response several proteins called RSBT break away from the large stressosome. This breakaway triggers a cascade of signals within the cell which results in over 150 proteins being produced - proteins which enable the cell to adapt, react and survive in its new environment.
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POPSScientists Identify Two Routes to Nerve Cell Regeneration In the long run, the optimal strategy for treating spinal injuries may involve a combination of therapies that restore neurons’ ability to grow axons and ones that counteract inhibitory signals near the injury. “You want to do each, and you may need to do both,”
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POPSVideo of the First 24 Hours of an Embryo's Cells The new technique, called Digital Scanned Laser Light-Sheet Fluorescence Microscopy, could be used on other animals such as mice, chicken and frogs, which would could help researchers better understand evolution at the cellular scale. Already, the research has shown that the initial stages of heart development do not happen as scientists thought.
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POPSRight and wrong lessons from biology The opposite view stresses that evolution is an extremely effective way of searching parameter space, and that in consequence is that we should assume that biological design solutions are likely to be close to optimal for the environment for which they’ve evolved. Where these design solutions seem odd from our point of view, their unfamiliarity is to be ascribed to the different ways in which physics works at the nanoscale. At its most extreme, this view regards biological nanotechnology, not just as the existence proof for nanotechnology, but as an upper limit on its capabilities.
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POPSGene silencer and quantum dots reduce protein production to a whisper
Each quantum dot was surrounded by a proton sponge that carried a positive charge. Without any quantum dots attached, the siRNA's negative charge would prevent it from penetrating a cell's wall. With the quantum-dot chaperone, the more weakly charged siRNA complex crosses the cellular wall, escapes from the endosome (a fatty bubble that surrounds incoming material) and accumulates in the cellular fluid, where it can do its work disrupting protein manufacture. Key to the newly published approach is that researchers can adjust the chemical makeup of the quantum dot's proton-sponge coating, allowing the scientists to precisely control how tightly the dots attach to the siRNA. Quantum dots were dramatically better than existing techniques at stopping gene activity. In experiments, a cell's production of a test protein dropped to 2 percent when siRNA was delivered with quantum dots. By contrast, the test protein was produced at 13 percent to 51 percent of normal levels when the siRNA
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POPSResearchers turn one form of adult mouse cell directly into another Joan Brugge, Chair of the Department of Cell Biology at Harvard Medical School, said the new study "provides exciting new insights into yet another aspect of cell plasticity that was not appreciated previously and that offers great potential therapeutically. Direct reprogramming represents a more straight-forward strategy to treat diseases involving loss of function of specific cell populations than approaches requiring an intermediate embryonic stem cell," she said.
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POPSGenetically engineered cells make their own nanomagnets, providing clear MRI images. If genetically engineering cells to produce their own magnetic nanoparticles proves successful, this provides a new window through which to view many biological processes as they unfold, from the formation of tumors to the migration of stem cells injected to treat disease. "It's just amazing that they can get a mammalian cell to actually make the material," says Lee Josephson, an associate professor at the Harvard Medical School's Center for Molecular Imaging Research. "I think it's a really meaningful piece of work."
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POPSBiologists on the Verge of Creating New Form of Life "We've made more progress on how the membrane of a protocell could grow and divide," Szostak said in a phone interview. "What we can do now is copy a limited set of simple sequences, but we need to be able to copy arbitrary sequences so that sequences could evolve that do something useful." By doing "something useful" for the cell, these genes would launch the new form of life down the Darwinian evolutionary path similar to the one that our oldest living ancestors must have traveled. Though where selective pressure will lead the new form of life is impossible to know.
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POPS68 Molecules that hold the key to all Cellular Life Currently, the vast majority of medical research looks to the human genome and proteome for answers, but those answers remain elusive, and perhaps for good reason. “We have now found instances where the pathogenesis of widespread and chronic diseases can be attributed to a change in the glycome, for example, in the absence of definable changes in the genome or proteome,” Marth said, adding that, as biomedical researchers, “we need to begin to cultivate the integration of disciplines in a holistic and rigorous way in order to perceive and most effectively manipulate the biological mechanisms of health and disease.” Marth believes that biology should become more integrative both in academic and research settings. “I’m one who believes that we don’t need to sacrifice breadth of knowledge in order to acquire depth of understanding.”
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POPS10 Amazing clips from the life sciences 1. "Building Body Parts from Scratch Last week, regenerative medicine researchers announced that they have grown a new windpipe for a woman who was crippled by tuberculosis. Years ago, other scientists were able to make bladders, from scratch, and implant them in children with malformed urinary tracts. This video shows some amazing footage from two tissue engineering labs'.
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POPS'Junk' DNA proves functional Over evolutionary time, these repeats were dispersed within different species, creating new regulatory sites throughout these genomes. Thus, the set of genes controlled by these transcription factors is likely to significantly differ from species to species and may be a major driver for evolution. This research also shows that these repeats are anything but "junk DNA," since they provide a great source of evolutionary variability and might hold the key to some of the important physical differences that distinguish humans from all other species. The GIS study also highlighted the functional importance of portions of the genome that are rich in repetitive sequences.
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POPS'Supermice' who can resist cancer and age almost half as fast as normal "By simultaneously increasing the amounts of telomerase and the resistance to cancer we are able to delay ageing in mice and also to extend their life span by 40 per cent," said Maria A. Blasco, from the Spanish National Cancer Research Centre (CNIO), who carried out the study with colleagues from Valencia University. "These mice get to live for as long as the eldest mice in records of the same kind. "If we were to parallel it to humans, then it would mean reaching 120 years of age and also to start ageing much later in life." Now the question is what will we do in the added time?
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POPSBacteria-human communication I think this double face of the pim gene, points to cellular levels where bacteria and human cell communicate and regulate co- benefitial existence. some say that the importance of this connection goes even beyond mere protection and peaceful co existence. interesting...
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