Toplam 121 içerik listeleniyor
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The genetic evolution of Zika virus
This is a phylogenetic tree constructed from nucleotide data from 41 viral complete ORF sequences of ZIKV strains An analysis comparing the individual differences between over 40 strains of Zika virus (30 isolated from humans, 10 from mosquitoes, and 1 from monkeys) has identified significant changes in both amino acid and nucleotide sequences during the past half-century. The data, published April 15 in Cell Host & Microbe, support a strong divergence between the Asian and African lineages as...
https://www.biyologlar.com/the-genetic-evolution-of-zika-virus-haber-8121 -
How the ant queen gets her crown: Uncovering the evolution of queen-worker differences
Queen and worker ants develop from the same sets of genes, but end up being structurally, behaviourally, and functionally different. Queen and worker ants develop from the same sets of genes, but perform completely different ecological roles. How the same genes result in two types of individuals is an ongoing mystery. In the past, scientists have only studied a small number of ant species at a time to try to understand the nature of queen-worker differences. However, a team from the Okinawa...
https://www.biyologlar.com/how-the-ant-queen-gets-her-crown-uncovering-the-evolution-of-queen-worker-differences-haber-8124 -
UW team stores digital images in DNA -- and retrieves them perfectly
Technology companies routinely build sprawling data centers to store all the baby pictures, financial transactions, funny cat videos and email messages its users hoard. But a new technique developed by University of Washington and Microsoft researchers could shrink the space needed to store digital data that today would fill a Walmart supercenter down to the size of a sugar cube. The team of computer scientists and electrical engineers has detailed one of the first complete systems to encode,...
https://www.biyologlar.com/uw-team-stores-digital-images-in-dna-and-retrieves-them-perfectly-haber-8723 -
Mitokondrial MTND1 Gen Mutasyonu İle İlişkili Lohn/Melas Örtüşme Sendromu
Mitokondrial MTND1 genindeki patojenik nokta mutasyonları daha önce iki farklı klinik fenotiple ilişkili olarak tanımlanmıştır –LHON ve MELAS -.Burada MTND1 geninde ,hem LHON hem de MELAS’ın klinik özelliklerini içeren bir örtüşme sendromu ile ilişkili ilk heteroplazmik mitokondrial DNA nokta mutasyonunu rapor ediyoruz.Kas histokimyasında ince mitokondrial anormallikler ortaya çıkmışken biyokimya analizinde izole bir kompleks I eksikliği...
https://www.biyologlar.com/mitokondrial-mtnd1-gen-mutasyonu-ile-iliskili-lohnmelas-ortusme-sendromu -
Mitokondrial MTND1 Gen Mutasyonu İle İlişkili Lohn/Melas Örtüşme Sendromu
Mitokondrial MTND1 genindeki patojenik nokta mutasyonları daha önce iki farklı klinik fenotiple ilişkili olarak tanımlanmıştır –LHON ve MELAS -.Burada MTND1 geninde ,hem LHON hem de MELAS’ın klinik özelliklerini içeren bir örtüşme sendromu ile ilişkili ilk heteroplazmik mitokondrial DNA nokta mutasyonunu rapor ediyoruz.Kas histokimyasında ince mitokondrial anormallikler ortaya çıkmışken biyokimya analizinde izole bir kompleks I eksikliği...
https://www.biyologlar.com/mitokondrial-mtnd1-gen-mutasyonu-ile-iliskili-lohnmelas-ortusme-sendromu -
Improving the delivery of chemotherapy with graphene
A new study published in IOP Publishing's journal 2D Materials has proposed using graphene as an alternative coating for catheters to improve the delivery of chemotherapy drugs. The research suggests that placing graphene - an extremely thin sheet of carbon atoms - on the internal surfaces of intravenous catheters commonly used to deliver chemotherapy drugs into a patient's body will improve the efficacy of treatments, and reduce the potential of the catheters breaking. The study indicates...
https://www.biyologlar.com/improving-the-delivery-of-chemotherapy-with-graphene -
New discovery in living cell signaling
A breakthrough discovery into how living cells process and respond to chemical information could help advance the development of treatments for a large number of cancers and other cellular disorders that have been resistant to therapy. An international collaboration of researchers, led by scientists with the U.S. Department of Energy (DOE)'s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley, have unlocked the secret behind the activation of the...
https://www.biyologlar.com/new-discovery-in-living-cell-signaling -
One of the last strongholds for Western chimpanzees
When Liberia enters the news it is usually in the context of civil war, economic crisis, poverty or a disease outbreak such as the recent emergence of Ebola in West Africa. Liberia's status as a biodiversity hotspot and the fact that it is home to some of the last viable and threatened wildlife populations in West Africa has received little media attention in the past. This is partly because the many years of violent conflict in Liberia, from 1989 to 1997 and from 2002 to 2003, thwarted efforts...
https://www.biyologlar.com/one-of-the-last-strongholds-for-western-chimpanzees -
Stem-cell-based strategy boosts immune system in mice
Raising hopes for cell-based therapies, UC San Francisco researchers have created the first functioning human thymus tissue from embryonic stem cells in the laboratory. The researchers showed that, in mice, the tissue can be used to foster the development of white blood cells the body needs to mount healthy immune responses and to prevent harmful autoimmune reactions. The scientists who developed the thymus cells — which caused the proliferation and maturation of functioning immune cells...
https://www.biyologlar.com/stem-cell-based-strategy-boosts-immune-system-in-mice -
Cecropia Güve Yaşam Döngüsü
Cecropia Güve Yaşam Döngüsü Meditate and wonder; Experience the marvel of a complete metamorphosis while listening to sumptuous music of Debussy and Holst. Witness events common to nature but rarely seen. Cecropia moth lifecycle metamorphosis is chronicled in detail. See a caterpillar eat its way out of the egg. Look as a larva changes from black; then yellow; to showing patterns and hues of orange, black, yellow, blue and green. Watch the caterpillar work out of its old 4rth instar...
https://www.biyologlar.com/cecropia-guve-yasam-dongusu -
New stem cells go back further
One of the obstacles to employing human embryonic stem cells for medical use lies in their very promise: They are born to rapidly differentiate into other cell types.
https://www.biyologlar.com/new-stem-cells-go-back-further -
Scientists discover an on-off switch for aging cells
Scientists at the Salk Institute have discovered an on-and-off "switch" in cells that may hold the key to healthy aging. This switch points to a way to encourage healthy cells to keep dividing and generating, for example, new lung or liver tissue, even in old age. In our bodies, newly divided cells constantly replenish lungs, skin, liver and other organs. However, most human cells cannot divide indefinitely–with each division, a cellular timekeeper at the ends of chromosomes shortens. When...
https://www.biyologlar.com/scientists-discover-an-on-off-switch-for-aging-cells -
Chip-based technology enables reliable direct detection of Ebola virus
A team led by researchers at UC Santa Cruz has developed chip-based technology for reliable detection of Ebola virus and other viral pathogens. The system uses direct optical detection of viral molecules and can be integrated into a simple, portable instrument for use in field situations where rapid, accurate detection of Ebola infections is needed to control outbreaks. Laboratory tests using preparations of Ebola virus and other hemorrhagic fever viruses showed that the system has the...
https://www.biyologlar.com/chip-based-technology-enables-reliable-direct-detection-of-ebola-virus -
Brain's on-off thirst switch identified
NEW YORK, NY (January 26, 2015)--Neurons that trigger our sense of thirst--and neurons that turn it off--have been identified by Columbia University Medical Center neuroscientists. The paper was published today in the online edition of Nature. For years, researchers have suspected that thirst is regulated by neurons in the subfornical organ (SFO), in the hypothalamus. But it has been difficult to pinpoint exactly which neurons are involved. "When researchers used electrical current to...
https://www.biyologlar.com/brains-on-off-thirst-switch-identified -
Stem cells might heal damaged lungs
Collectively, such diseases of the airways as emphysema, bronchitis, asthma and cystic fibrosis are the second leading cause of death worldwide.
https://www.biyologlar.com/stem-cells-might-heal-damaged-lungs -
Closing the case on an ancient archeological mystery
Climate change may be responsible for the abrupt collapse of civilization on the fringes of the Tibetan Plateau around 2000 B.C. WSU archaeologist Jade D'Alpoim Guedes and an international team of researchers found that cooling global temperatures at the end of the Holocene Climatic Optimum, a 4,000 year period of warm weather, would have made it impossible for ancient people on the Tibetan Plateau to cultivate millet, their primary food source. Guedes' team's research recently was published...
https://www.biyologlar.com/closing-the-case-on-an-ancient-archeological-mystery -
Restoring vision with stem cells
Age-related macular degeneration (AMRD) could be treated by transplanting photoreceptors produced by the directed differentiation of stem cells, thanks to findings published today by Professor Gilbert Bernier of the University of Montreal and its affiliated Maisonneuve-Rosemont Hospital. ARMD is a common eye problem caused by the loss of cones. Bernier's team has developed a highly effective in vitro technique for producing light sensitive retina cells from human embryonic stem cells. "Our...
https://www.biyologlar.com/restoring-vision-with-stem-cells -
Shiny fish skin inspires nanoscale light reflectors
A nature-inspired method to model the reflection of light from the skin of silvery fish and other organisms may be possible, according to Penn State researchers. Such a technique may be applicable to developing better broadband reflectors and custom multi-spectral filters for a wide variety of applications, including advanced optical coatings for glass, laser protection, infrared imaging systems, optical communication systems and photovoltaics, according to Douglas Werner, John L. and...
https://www.biyologlar.com/shiny-fish-skin-inspires-nanoscale-light-reflectors -
Proteomics identifies DNA repair toolbox
During each cell division, more than 3.3 billion base pairs of genomic DNA have to be duplicated and segregated accurately to daughter cells. But what happens when the DNA template is damaged in such a way that the replication machinery gets stuck?
https://www.biyologlar.com/proteomics-identifies-dna-repair-toolbox -
Odd histone helps suppress jumping genes in stem cells, study says
A family of proteins known as histones provides support and structure to DNA, but for years, scientists have been puzzling over occasional outliers among these histones, which appear to exist for specific, but often mysterious reasons. Now, researchers have uncovered a new purpose for one such histone variant: preventing genetic mutations by keeping certain so-called "jumping genes" in place. This research, which began at Rockefeller University and was published May 4 in Nature, reveals a...
https://www.biyologlar.com/odd-histone-helps-suppress-jumping-genes-in-stem-cells-study-says -
Hacking the programs of cancer stem cells
All tumor cells are the offspring of a single, aberrant cell, but they are not all alike. Only a few retain the capacity of the original cell to create an entire tumor.
https://www.biyologlar.com/hacking-the-programs-of-cancer-stem-cells -
Oncogene controls stem cells in early embryonic development
After a gestation period of around ten months, fawns are born in early summer - when the weather is warm and food is plentiful for the mother. Six months would actually be enough for the embryo's development, but then offspring from mating in the later portion of summer would be born in winter. Therefore, nature prolongs the gestation period by a hormone-regulated pause in the development of the early embryos. Many animal species use this process, called diapause, to adjust their reproduction...
https://www.biyologlar.com/oncogene-controls-stem-cells-in-early-embryonic-development -
Decaying RNA molecules tell a story
Once messenger RNA (mRNA) has done its job - conveying the information to produce the proteins necessary for a cell to function - it is no longer required and is degraded. Scientists have long thought that the decay started after translation was complete and that decaying RNA molecules provided little biological information. Now a team from EMBL Heidelberg and Stanford University led by Lars Steinmetz has turned this on its head in an article published in Cell. The researchers have shown that...
https://www.biyologlar.com/decaying-rna-molecules-tell-a-story -
West Coast scientists sound alarm for changing ocean chemistry
The ocean chemistry along the West Coast of North America is changing rapidly because of global carbon dioxide emissions, and the governments of Oregon, California, Washington and British Columbia can take actions now to offset and mitigate the effects of these changes. That is the conclusion of a 20-member panel of leading West Coast ocean scientists, who presented a comprehensive report on Monday outlining a series of recommendations to address the increase in ocean acidification and...
https://www.biyologlar.com/west-coast-scientists-sound-alarm-for-changing-ocean-chemistry -
Clues contained in ancient brain point to the origin of heads in early animals
A new study from the University of Cambridge has identified one of the oldest fossil brains ever discovered - more than 500 million years old - and used it to help determine how heads first evolved in early animals. The results, published today (7 May) in the journal Current Biology, identify a key point in the evolutionary transition from soft to hard bodies in early ancestors of arthropods, the group that contains modern insects, crustaceans and spiders. The study looked at two types of...
https://www.biyologlar.com/clues-contained-in-ancient-brain-point-to-the-origin-of-heads-in-early-animals -
Tiny genetic tweak unlocked corn kernels during domestication
If not for a single genetic mutation, each kernel on a juicy corn cob would be trapped inside a inedible casing as tough as a walnut shell. The mutation switches one amino acid for another at a specific position in a protein regulating formation of these shells in modern corn's wild ancestor, according to a study published in the July 2015 issue of GENETICS, a publication of the Genetics Society of America. "Humans completely reshaped the ancestor of corn, effectively turning the cob inside...
https://www.biyologlar.com/tiny-genetic-tweak-unlocked-corn-kernels-during-domestication -
Quantum dots with impermeable shell: A powerful tool for nanoengineering
Images of ZnO quantum dots prepared by the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw, taken by transmission electron microscopy. False colors.
https://www.biyologlar.com/quantum-dots-with-impermeable-shell-a-powerful-tool-for-nanoengineering -
Quantum dots with impermeable shell: A powerful tool for nanoengineering
Images of ZnO quantum dots prepared by the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw, taken by transmission electron microscopy. False colors.
https://www.biyologlar.com/quantum-dots-with-impermeable-shell-a-powerful-tool-for-nanoengineering -
In some genetic cases of microcephaly, stem cells fail to launch
In a very severe, genetic form of microcephaly, stem cells in the brain fail to divide, according to a new Columbia University Medical Center study that may provide important clues to understanding how the Zika virus affects the developing brain.
https://www.biyologlar.com/in-some-genetic-cases-of-microcephaly-stem-cells-fail-to-launch -
Atomic view of microtubules
Microtubules, hollow fibers of tubulin protein only a few nanometers in diameter, form the cytoskeletons of living cells and play a crucial role in cell division (mitosis) through their ability to undergo rapid growth and shrinkage, a property called "dynamic instability." Through a combination of high-resolution cryo-electron microscopy (cryo-EM) and a unique methodology for image analysis, a team of researchers with Berkeley Lab and the University of California (UC) Berkeley has produced an...
https://www.biyologlar.com/atomic-view-of-microtubules -
Inside the Collections: Paleontology and Big Bone Room
Paleontology Collections Manager Carl Mehling gives us a behind-the-scenes tour of the Big Bone Room, which houses some of the largest items in the Paleontology collection. Its holdings include one of the largest complete limb bones in the world: the 650-pound thigh bone of the long-necked, plant-eating dinosaur Camarasaurus. More than 3 million specimens make up the Museum's world-class paleontology collections, and only a small fraction can be displayed at any given time. In fact,...
https://www.biyologlar.com/inside-the-collections-paleontology-and-big-bone-room -
Deciphering the olfactory receptor code
In animals, numerous behaviors are governed by the olfactory perception of their surrounding world. Whether originating in the nose of a mammal or the antennas of an insect, perception results from the combined activation of multiple receptors located in these organs. Identifying the full repertoire of receptors stimulated by a given odorant would represent a key step in deciphering the code that mediates these behaviors. To this end, a tool that provides a complete olfactory receptor signature...
https://www.biyologlar.com/deciphering-the-olfactory-receptor-code -
A new twist in genetic switches
Rice University researchers have a new twist for those clinging to old ideas about a basic biological process. The Rice lab of theoretical biological physicist Peter Wolynes reported this week that the activity of a master regulator in cells is determined by kinetics, a notion that counters decades-old classical models in molecular biology that attribute the control of genetic processes to the thermodynamics of biochemical reactions. The genetic switch in question relies on a recently...
https://www.biyologlar.com/a-new-twist-in-genetic-switches -
Discovery of a salamander in amber sheds light on evolution of Caribbean islands
More than 20 million years ago, a short struggle took place in what is now the Dominican Republic, resulting in one animal getting its leg bitten off by a predator just before it escaped. But in the confusion, it fell into a gooey resin deposit, to be fossilized and entombed forever in amber. The fossil record of that event has revealed something not known before - that salamanders once lived on an island in the Caribbean Sea. Today, they are nowhere to be found in the entire Caribbean...
https://www.biyologlar.com/discovery-of-a-salamander-in-amber-sheds-light-on-evolution-of-caribbean-islands -
Tail as old as time -- researchers trace ankylosaur's tail evolution
How did the ankylosaur get its tail club? According to research from North Carolina State University and the North Carolina Museum of Natural Sciences that traces the evolution of the ankylosaur's distinctive tail, the handle arrived first on the scene, and the knot at the end of the tail followed. The typical ankylosaur had a wide armored body and a flexible tail. But one group of ankylosaurs - ankylosaurids - also had a tail club that could have served as a useful weapon. These "weaponized"...
https://www.biyologlar.com/tail-as-old-as-time-researchers-trace-ankylosaurs-tail-evolution -
A marine creature's magic trick explained
Tiny ocean creatures known as sea sapphires perform a sort of magic trick as they swim: One second they appear in splendid iridescent shades of blue, purple or green, and the next they may turn invisible (at least the blue ones turn completely transparent). How do they get their bright colors and what enables them to "disappear?" New research at the Weizmann Institute has solved the mystery of these colorful, vanishing creatures, which are known scientifically as Sapphirinidae. The findings,...
https://www.biyologlar.com/a-marine-creatures-magic-trick-explained -
Some things are too good to be true: Lycaenid butterfly larvae manipulate ants
Project Assistant Professor HOJO Masaru of Kobe University, Graduate School of Science, and joint research groups at the University of the Ryukyus and Harvard University have discovered that lycaenid butterfly larvae, which are in a symbiotic relationship with ants, can control the effect of dopamine by supplying the ants with nectar. The results of this study provide novel insight into the phenomenon of symbiosis and give clues about the physiological functions of dopamine. The study was...
https://www.biyologlar.com/some-things-are-too-good-to-be-true-lycaenid-butterfly-larvae-manipulate-ants -
New DNA research reveals genetic heritage of elusive vaquita
A new method of teasing information from scarce and highly degraded genetic samples is helping NOAA Fisheries and Mexican scientists unravel the genetic heritage of the enigmatic vaquita, the most endangered marine mammal on Earth. Genetic studies are important to the international effort to conserve the vaquita because the DNA that holds their genetic code can unlock the secrets of how they came to be. For instance, it can reveal the story of how - and how long ago - the animals evolved into...
https://www.biyologlar.com/new-dna-research-reveals-genetic-heritage-of-elusive-vaquita -
New DNA research reveals genetic heritage of elusive vaquita
A new method of teasing information from scarce and highly degraded genetic samples is helping NOAA Fisheries and Mexican scientists unravel the genetic heritage of the enigmatic vaquita, the most endangered marine mammal on Earth. Genetic studies are important to the international effort to conserve the vaquita because the DNA that holds their genetic code can unlock the secrets of how they came to be. For instance, it can reveal the story of how - and how long ago - the animals evolved into...
https://www.biyologlar.com/new-dna-research-reveals-genetic-heritage-of-elusive-vaquita -
Zooming in on bacterial weapons in 3-D
The plague, bacterial dysentery, and cholera have one thing in common: These dangerous diseases are caused by bacteria which infect their host using a sophisticated injection apparatus. Through needle-like structures, they release molecular agents into their host cell, thereby evading the immune response. Researchers at the Max Planck Institute for Biophysical Chemistry in Göttingen in cooperation with colleagues at the Max Planck Institute for Infection Biology in Berlin and the University of...
https://www.biyologlar.com/zooming-in-on-bacterial-weapons-in-3-d -
3-D motion of cold virus offers hope for improved drugs using Australia's fastest supercomputer
Melbourne researchers are now simulating in 3D, the motion of the complete human rhinovirus, the most frequent cause of the common cold, on Australia's fastest supercomputer, paving the way for new drug development. Rhinovirus infection is linked to about 70 per cent of all asthma exacerbations with more than 50 per cent of these patients requiring hospitalisation. Furthermore, over 35 per cent of patients with acute chronic obstructive pulmonary disease (COPD) are hospitalised each year due...
https://www.biyologlar.com/3-d-motion-of-cold-virus-offers-hope-for-improved-drugs-using-australias-fastest-supercomputer -
'Fourth strand' of European ancestry originated with hunter-gatherers isolated by Ice Age
The first sequencing of ancient genomes extracted from human remains that date back to the Late Upper Palaeolithic period over 13,000 years ago has revealed a previously unknown "fourth strand" of ancient European ancestry. This new lineage stems from populations of hunter-gatherers that split from western hunter-gatherers shortly after the 'out of Africa' expansion some 45,000 years ago and went on to settle in the Caucasus region, where southern Russia meets Georgia today. Here these...
https://www.biyologlar.com/fourth-strand-of-european-ancestry-originated-with-hunter-gatherers-isolated-by-ice-age -
New insights into a virus proteome
The genome encodes the complete information needed by an organism, including that required for protein production. Viruses, which are up to a thousand times smaller than human cells, have considerably smaller genomes. Using a type of herpesvirus as a model system, the scientists of the Max Planck Institute of Biochemistry in Martinsried near Munich and their collaboration partners at the University of California in San Francisco have shown that the genome of this virus contains much more...
https://www.biyologlar.com/new-insights-into-a-virus-proteome -
Marine animals use new form of secret light communication
Researchers from the Queensland Brain Institute at The University of Queensland have uncovered a new form of secret light communication used by marine animals. The findings may have applications in satellite remote sensing, biomedical imaging, cancer detection, and computer data storage. Dr Yakir Gagnon, Professor Justin Marshall and colleagues previously showed that mantis shrimp (Gonodactylaceus falcatus) can reflect and detect circular polarising light, an ability extremely rare in nature....
https://www.biyologlar.com/marine-animals-use-new-form-of-secret-light-communication -
Scientists report world's first herbivorous filter-feeding marine reptile
Some strange creatures cropped up in the wake of one of Earth's biggest mass extinctions 252 million years ago. In 2014, scientists discovered a bizarre fossil--a crocodile-sized sea-dwelling reptile,
https://www.biyologlar.com/scientists-report-worlds-first-herbivorous-filter-feeding-marine-reptile -
Scientists report world's first herbivorous filter-feeding marine reptile
Some strange creatures cropped up in the wake of one of Earth's biggest mass extinctions 252 million years ago. In 2014, scientists discovered a bizarre fossil--a crocodile-sized sea-dwelling reptile,
https://www.biyologlar.com/scientists-report-worlds-first-herbivorous-filter-feeding-marine-reptile -
May repairs full of mistakes develop into cancer?
These are DNA double-strand breaks, introduced by ionizing radiation or other mechanisms, are repaired rapidly and precisely in normal cells (right pathway). In contrast, compromised Tel1 activation with inefficient end...
https://www.biyologlar.com/may-repairs-full-of-mistakes-develop-into-cancer -
May repairs full of mistakes develop into cancer?
These are DNA double-strand breaks, introduced by ionizing radiation or other mechanisms, are repaired rapidly and precisely in normal cells (right pathway). In contrast, compromised Tel1 activation with inefficient end...
https://www.biyologlar.com/may-repairs-full-of-mistakes-develop-into-cancer -
Hydra can modify its genetic program
Champion of regeneration, the freshwater polyp Hydra is capable of reforming a complete individual from any fragment of its body. It is even able to remain alive when all its neurons have disappeared. Researcher the University of Geneva (UNIGE), Switzerland, have discovered how: cells of the epithelial type modify their genetic program by overexpressing a series of genes, among which some are involved in diverse nervous functions. Studying Hydra cellular plasticity may thus influence research...
https://www.biyologlar.com/hydra-can-modify-its-genetic-program -
Hydra can modify its genetic program
Champion of regeneration, the freshwater polyp Hydra is capable of reforming a complete individual from any fragment of its body. It is even able to remain alive when all its neurons have disappeared. Researcher the University of Geneva (UNIGE), Switzerland, have discovered how: cells of the epithelial type modify their genetic program by overexpressing a series of genes, among which some are involved in diverse nervous functions. Studying Hydra cellular plasticity may thus influence research...
https://www.biyologlar.com/hydra-can-modify-its-genetic-program