Amazing Science
394.1K views | +307 today
Amazing Science
Amazing science facts - 3D_printing • aging • AI • anthropology • art • astronomy • bigdata • bioinformatics • biology • biotech • chemistry • computers • cosmology • education • environment • evolution • future • genetics • genomics • geosciences • green_energy • history • language • map • material_science • math • med • medicine • microscopy • nanotech • neuroscience • paleontology • photography • photonics • physics • postings • robotics • science • technology • video
Your new post is loading...
Scooped by Dr. Stefan Gruenwald!

Bacteria with vuvuzelas use a channel protein as a syringe for injecting a cocktail of toxins

Bacteria with vuvuzelas use a channel protein as a syringe for injecting a cocktail of toxins | Amazing Science |

The bacterium Photorhabdus luminescens is a constant companion of some roundworms. These worms assault insect larvae, thereby infecting them with the bacteria; the pathogens then attack the cells of their victims with a deadly cocktail of various toxins. Scientists at the Max Planck Institute of Molecular Physiology in Dortmund working together with colleagues from Freiburg University and Jacobs University Bremen, have discovered that the bacteria use an important toxin complex like a syringe. It makes its way into the host cells via constricted vesicles in the cell membranes, and modifies their structure from within.


Part of the toxin complex then forces its way inside the cell through the vesicle membrane by means of a vuvuzela-like protein channel, and kills the cell. Important toxins of Photorhabdus luminescens are counted among the ABC toxins, which consist of the three protein components TcA, TcB and TcC. The toxin complex first docks at receptor molecules on the membrane of the host cell and is sucked inside the cell in small membrane blisters called vesicles. The TcC components then make their way into the cell fluid and demolish the cell’s protein skeleton. What has remained unclear to date, however, was how the protein managed to get through the vesicle membrane.


Now, for the first time, scientists have been able to decode the structure ofPhotorhabdus luminescens’ ABC toxins using cryoelectron microscopy and single particle analysis. This shows that the bacterium’s TcA protein consists of five subunits that together form the shape of a bell. “Inside the bell, the subunits form a channel that has one wide and one narrow aperture, so that it looks like the notorious vuvuzela horn used by South African football fans”, explains Stefan Raunser of the Max Planck Institute of Molecular Physiology.

No comment yet.
Rescooped by Dr. Stefan Gruenwald from Longevity science!

Wonderwall: High-tech home-assisted living for the elderly

Wonderwall: High-tech home-assisted living for the elderly | Amazing Science |

Researchers from the Munich University of Technology (TUM) have created a high-tech wall designed to help the elderly continue to live at home by providing assistance in everyday tasks and monitoring their health. The "wonderwall" can find misplaced keys and glasses, check blood pressure and blood sugar levels and, in the event of a critical health problem, call the local doctor or mobile nursing service.


The Living independently in Südtirol / Alto Adige (LISA) project headed up by Human Ambient Technologies Lab at TUM is showcasing the wonderwalls system in a "smart entrance hall" that will be unveiled on February 20 at Munich Creative Business Week.


Based around a tablet computer mounted in its wardrobe-like panel, the wonderwall system blends into the look of a normal house – it even comes with all the usual hall fittings, including coat hooks and even a shoe horn right at the bottom.


It features an “indoor positioning system” that keeps track of mislaid items like keys and has an integrated air conditioning system which automatically keeps air circulating in the apartment if the resident forgets to turn it on.

The system also includes with biosensors which zero in on key vital signs like blood pressure and blood sugar levels. After assessing the health of the individual, it could be programmed to come up with suggestions like going out for walk, or perhaps even suggest medication. If things turn critical, it can notify a physician or other health professionals who can also be hooked into the system to regularly check on the patient.

Via Ray and Terry's
No comment yet.
Rescooped by Dr. Stefan Gruenwald from Longevity science!

Engineered artificial human livers for drug testing and discovery

Engineered artificial human livers for drug testing and discovery | Amazing Science |

Institute of Bioengineering and Nanotechnology (IBN) researchers have engineered an artificial human liver that mimics the natural tissue environment closely.


The development makes it possible for companies to predict the toxicity of new drugs earlier, potentially speeding up the drug development process and reducing the cost of manufacturing



Via Ray and Terry's
No comment yet.
Scooped by Dr. Stefan Gruenwald!

MRI Fingerprinting: The 12-second scan that fingerprints tissues and diseases

MRI Fingerprinting: The 12-second scan that fingerprints tissues and diseases | Amazing Science |

Getting an MRI can be an uncomfortable experience, particularly for a 40-minute or longer scan. In the US at least, it is also quite expensive—the same kind of scan costing just over $100 in France, for example, would undoubtedly cost over $1000 here. If the whole scan could be done in say, 12 seconds, the call to "make the patient the customer again" might be heard a little clearer. A new technique developed by a collaborative effort at Case Western University and Siemens, known as MRI Fingerprinting (MRF), promises to do just that.

While MRI is in principle a quantitative instrument, in practice, the results are typically best described as qualitative. If it were really quantitative, caregivers would probably discuss features of the scan more in terms of absolutes, ideally suffixed with appropriate units. Instead, we usually settle for the familiar, regions of hyper, or hypointensity to describe regions of anomaly.

MRF would be performed using the standard MRI hardware, but it draws on a set of new signal processing techniques falling under the rubric of compressive sampling. Engineers have been hammering out a novel approach to a broad class of problems arising in everything from telecommunications, to image acquisition and processing. Most recently in medicine, compressive sampling, or random sampling as it is sometimes called, has been applied to create high resolution endoscopic images.

To analogize how these new methods might actually work, let's imagine acquiring a natural image. It can be shown that if the image is acquired through a psuedo-random mask of sorts, much greater efficiency can generally be achieved. Intuitively we might expect that if the first 300 pixels of a seascape, for example, are all highly correlated blue sky, perhaps structuring the pixel acquisition in some other way could be more efficient.

The metaphor is obviously a simplification, but the key for MRF is rather than using rigidly defined and error-prone scans on the front end, all the data can be acquired up front using compressive sampling. Afterwards, pattern recognition techniques can be used in the post processing. While the fingerprint is not to be understood literally as a kind of DNA fingerprinting as used in forensic science, the process resembles matching a person's fingerprint to a database that can then draw up additional related information.

Following acquisition of the imaging data, a so-called "dictionary" containing the realistic range of standard MRI parameters (like relaxation times and off-resonance frequency) can be obtained with relatively modest computing resource. Other properties often obtained from MRI data such as diffusion and magnetization transfer can also be measured. These are the parameters behind the techniques now at our disposal for tracing the paths of axon tracts in the brain, in particular diffusion tractoctagraphy. The authors of the study conclude that in using MRF, the traditional imaging routine will be greatly simplified into an all-in-one scan. The dozens of parameters under operator control in current MRI machines could be replaced with a simple scan button, making MRI more routine, patient-friendly, and affordable.

No comment yet.
Scooped by Dr. Stefan Gruenwald!

Red Silver, Green Gold? Nanotechnology Can Change The Color Of Metals

Red Silver, Green Gold? Nanotechnology Can Change The Color Of Metals | Amazing Science |

British scientists have found a way of changing the color of metals including gold, silver and aluminium. The breakthrough, described in a paper in the Journal of Optics, opens up the prospect of coloring metals without having to coat or chemically treat them.

“This is the first time the visible color of metal has been changed in this way,” said Prof Nikolay Zheludev of the University of Southampton’s Optoelectronics Research Center, senior author of the study. “The colors of the objects we see all around us are determined by the way light interacts with those objects. For instance, an object that reflects red light but absorbs other wavelengths will appear red to the human eye.”


“This is the fundamental principle we have exploited in this project,” he said. “By embossing metals with patterns only around 100 nanometers across, we’ve found that we can control which wavelengths of light the metal absorbs and which it reflects.”


The precise shape and height or depth of the patterns determine exactly how light behaves when it strikes the metal and therefore what color is created. The technique can be used to produce a wide range of colors on a given metal.


“A silver ring, for example, could be decorated with a number of different patterns, making one part of it appear red, another part green and so on; metal features with sophisticated optical properties that would be almost impossible to imitate could be incorporated into documents as security features.”


The nano-patterning is carried out at the research level using well-established techniques such as ion beam milling, which may be envisaged as sand-blasting on the atomic scale.

No comment yet.
Scooped by Dr. Stefan Gruenwald!

Potential Treatment for Ebola and Rabies Discovered

Potential Treatment for Ebola and Rabies Discovered | Amazing Science |

A molecule related to plant-derived compounds known as indoline alkaloids appears to block crucial elements of replication in nonsegmented, negative sense (NNS) RNA viruses, an order that includes such unsavory members as Ebola, rabies and measles. The molecule, CMLDBU3402, could become the basis for an effective, broad-spectrum therapy to treat NNS viruses, according to the study, published today in the journal Chemistry & Biology.


There are currently no effective therapies or vaccines for many NNS viruses, several of which are highly contagious and have high mortality rates. Ebola, for example, can kill 90 percent of those infected.


Researchers in the study first identified a number of chemotypes that had not previously been screened for potential activity against NNS viruses. They identified several molecules within this group that appeared to inhibit infection in cells exposed to Ebola or another NNS virus, vesicular stomatitis, which primarily affects cattle, horses and swine.


The newly discovered compounds are illustrated as green molecules “blocking” the spread of orange Ebola virus virions from an infected cell. Image created by Claire Marie Filone and John Connor; Ebola virus micrograph by Chris Reed at USAMRIID.


The most promising compound in the study — CMLDBU3402 — appeared to target viral RNA-dependent RNA polymerase (RdRp). RdRp is required for many aspects of RNA synthesis, which is how one virus replicates to become many. The enzyme is produced by all NNS viruses and inhibiting it appears to block transcription, preventing the spread of infection in the host.


Because RdRp is found in all NNS viruses and is necessary for replication, researchers believe molecule CMLDBU3402 can be used to develop a treatment for the entire virus order, potentially wiping out not just Ebola and newer NNS discoveries such as the Nipah and Hendra viruses, but also old scourges including rabies, mumps and measles.

No comment yet.
Scooped by Dr. Stefan Gruenwald!

Big Bang inflation model confirmation indicates ‘infinite number of universes’ exist

Big Bang inflation model confirmation indicates ‘infinite number of universes’ exist | Amazing Science |

Scientists just announced the exciting results of the European Space Agency’s Planck space probe experiment, which observed conditions about the universe in the milliseconds after the Big Bang by looking at background radiation in the sky. They found that scientists’ theory of inflation—that the universe expanded in a sudden rush in a fraction of a second after the Big Bang—was actually correct. Which is pretty incredible, because the theory had been based sheerly on abstract math. Lo and behold, the first observable data about the moments directly after the Big Bang show the inflation model is exactly what actually happened.


“We’ve uncovered a fundamental truth of the universe,” said George Efstathiou of Cambridge University, who announced the results. They also uncovered some additional little details, like the universe is about 80 million years older than scientists had thought, and filled with slightly more regular matter and less dark matter than they’d thought.


So you’d think all the scientists would be psyched, right? Pats on the back, champagne all around. Especially the guys who camee up with the inflation theory in the first place—it’s widely thought they could win a Nobel Prize.

Except those guys are troubled.


Associated Press reports: Efstathiou said the pioneers of inflation theory should start thinking about their own Nobel prizes. Two of those theorists – Paul Steinhardt of Princeton and Andreas Albrecht of University of California Davis – said before the announcement that they were sort of hoping that their inflation theory would not be bolstered.


That’s because taking inflation a step further leads to a sticky situation: An infinite number of universes.


In order for inflation theory to work—and it was confirmed as being a reality yesterday—”that split-second of expansion may not stop elsewhere like it does in the observable universe,” the scientists say. “That means,” notes AP, “there are places where expansion is zooming fast, with an infinite number of universes that stretch to infinity.”


So the idea of an infinite number of universes existing in parallel to our own universe is now no longer the stuff of sci-fi, but the most likely reality as interpreted by our most advanced science.


“You can get very, very strange answers to problems when you start thinking about what different observers might see in different universes,” Efstathiou said.

No comment yet.
Scooped by Dr. Stefan Gruenwald!

Engineered immune cells battle acute leukemia into retreat

Engineered immune cells battle acute leukemia into retreat | Amazing Science |

Modified T cells seek out and destroy blood cancer.


Genetically engineered immune cells can drive an aggressive type of leukemia into retreat, a small clinical trial suggests. The results of the trial — done in five patients with acute lymphoblastic leukemia and represent the latest success for a 'fringe' therapy in which a type of immune cell called T cells are extracted from a patient, genetically modified, and then reinfused back. In this case, the T cells were engineered to express a receptor for a protein on other immune cells, known as B cells, found in both healthy and cancerous tissue.

When reintroduced into the patients, the tricked T cells quickly homed in on their targets. “All of our patients very rapidly cleared the tumor,” says Michel Sadelain, a researcher at the Memorial Sloan-Kettering Cancer Center in New York and an author of the study. The treatment “worked much faster than we thought”.

The technique has already shown promise against chronic leukemia, but there were doubts about whether it could take on the faster-growing acute lymphoblastic leukemia, a tenacious disease that kills more than 60% of those afflicted.  

Carl June, an immunologist at the University of Pennsylvania in Philadelphia and a pioneer in engineering T cells to fight cancer, says that he is surprised that the method worked so well against such a swift-growing cancer. The next step, he says, is to move the technique out of the ‘boutique’ academic cancer centres that developed it and into multicentre clinical trials.


Oncologist Renier Brentjens, also at Memorial Sloan-Kettering Cancer Center, remembers the day that he had to tell one of the patients in the trial that the weeks of high-dose chemotherapy the 58-year-old man had endured had not worked after all. “It was painful to have that conversation,” says Brentjens. “He tells me now it was the worst news he has ever heard in his life.”


Another month in the hospital on intensive chemotherapy drugs did nothing to help. By the time the man started the trial, 70% of his bone marrow was tumour. Brentjens, Sadelain and their colleagues then extracted T cells from the patient and engineered them to express a ‘chimeric antigen receptor’, or CAR, that would target cells expressing a protein called CD19. Because CD19 is found on both healthy and cancerous B cells, the engineered T cells were unable to discriminate between the two. However, patients can live without B cells.

By two weeks after the procedure, the patient was showing signs of improvement. The treatment had driven his cancer into remission — as it did for the other four patients in the trial — so he became eligible for a bone-marrow transplant. A hundred days later, he is doing well, says Brentjens. Four of the five patients were well enough to receive transplants; the remaining patient relapsed and was ineligible.


Pharmaceutical firms have tended to be wary of the CAR technique because it is technically challenging, must be personalized to the patient and faces an untested path to regulatory approval, says Steven Rosenberg, head of the tumour immunology section at the National Cancer Institute in Bethesda, Maryland.


But this seems to be changing. Rosenberg points to a collaboration formed in August last year between June's group and the drug giant Novartis, as well as the launch of several small CAR-focused biotechnology firms. And Sadelein says that he is an investigator on a trial with the Dana-Farber Cancer Institute in Boston, Massachusetts, to test whether the technique can be exported to other treatment centers, among other outcomes.

Elias Açaf's comment, June 1, 2013 10:17 AM
so interesting !
Scooped by Dr. Stefan Gruenwald!

Big Bang’s afterglow shows universe is 80 million years older than scientists thought

Big Bang’s afterglow shows universe is 80 million years older than scientists thought | Amazing Science |

A new examination of what is essentially the universe’s birth certificate allows astronomers to tweak the age, girth and speed of the cosmos, more secure in their knowledge of how it evolved, what it’s made of and its ultimate fate.


Sure, the universe suddenly seems to be showing its age, now calculated at 13.8 billion years — 80 million years older than scientists had thought. It’s got about 3 percent more girth — technically it’s more matter than mysterious dark energy — and it is expanding about 3 percent more slowly.


But with all that comes the wisdom for humanity. Scientists seem to have gotten a good handle on the Big Bang and what happened just afterward, and may actually understand a bit more about the cosmic question of how we are where we are.


All from a baby picture of fossilized light and sound.The snapshot from a European satellite had scientists from Paris to Washington celebrating a cosmic victory of knowledge Thursday — basic precepts that go back all the way to Einstein and relativity.


The Planck space telescope mapped background radiation from the early universe — now calculated at about 13.8 billion years old. The results bolstered a key theory called “inflation,” which says the universe burst from subatomic size to its vast expanse in a fraction of a second just after the Big Bang that created the cosmos.


“We’ve uncovered a fundamental truth of the universe,” said George Efstathiou, director of the Kavli Institute for Cosmology at the University of Cambridge who announced the Planck findings in Paris. “There’s less stuff that we don’t understand by a tiny amount.”


The map of the universe’s evolution — in sound echoes and fossilized light going back billions of years — reinforces some predictions made decades ago solely on the basis of mathematical concepts.


“We understand the very early universe potentially better than we understand the bottom of our oceans,” said Bob Nichols, director of the Institute of Cosmology and Gravitation at the University of Portsmouth in Britain. “We as humanity put a satellite into space, we predicted what it should see and saw it.”

No comment yet.
Scooped by Dr. Stefan Gruenwald!

Researchers publish final version of full Neanderthal genome

Researchers publish final version of full Neanderthal genome | Amazing Science |

In 2010, Dr. Svante Pääbo and his colleagues presented the first draft version of the Neandertal genome from data collected from three bones found in a cave in Croatia. They have now used a toe bone excavated in 2010 in Denisova Cave in southern Siberia to generate a high-quality genome from a single Neandertal individual.


The Leipzig team has used sensitive techniques they have developed over the past two years to sequence every position in the genome about 50 times over, using DNA extracted from 0.038 grams of the toe bone. The analysis of the genome together with partial genome sequences from other Neandertals, and the genome from a small finger bone discovered in the same cave, shows that the individual is closely related to other Neandertals in Europe and western Russia (see Figure).


Remarkably, Neandertals and their relatives, Denisovans, were both present in this unique cave in the Altai Mountains on the border between Russia, China, Mongolia and Kazakhstan. In the 2010 draft version of the Neandertal genome, each position was determined, on average, once. In the now-completed version of the genome every position was determined on average 50 times over. This allows even the small differences between the copies of genes that this Neandertal individual inherited from its mother and father to be distinguished. Today, the Leipzig group makes the entire Neandertal genome sequence available for the scientific community over the internet. "The genome is of very high quality", says Dr. Kay Prüfer, who coordinates the analyses of the genome in Leipzig. "It matches the quality of the Denisovan genome, presented last year, and is as good as or even better than the multiple present-day human genomes available to date."


"We are in the process of comparing this Neandertal genome to the Denisovan genome as well as to the draft genomes of other Neandertals. We will gain insights into many aspects of the history of both Neandertals and Denisovans and refine our knowledge about the genetic changes that occurred in the genomes of modern humans after they parted ways with the ancestors of Neandertals and Denisovans" says Pääbo. The group will present a paper describing the genome later this year. "But we make the genome sequence freely available now to allow other scientists to profit from it even before it is published" says Pääbo. The project is made possible by financing from the Max Planck Society and is part of efforts since almost 30 years by Dr. Pääbo's group to study ancient DNA. The toe bone was discovered by Professor Anatoly Derevianko and Professor Michael Shunkov from the Russian Academy of Sciences in 2010 during their excavations at Denisova Cave, a unique archaeological site which contains cultural layers indicating that human occupation at the site started up to 280,000 years ago.

No comment yet.
Scooped by Dr. Stefan Gruenwald!

Jagged ice blades may threaten future landing on Jupiter's icy moon Europa

Jagged ice blades may threaten future landing on Jupiter's icy moon Europa | Amazing Science |

Jupiter's icy moon Europa is a prime target for future space missions as it harbours a buried ocean that could have the right conditions for life.

But attempts to land may face a major hazard: jagged "blades" of ice up to 10m long.


A major US conference has heard the moon may have ideal conditions for icy spikes called "penitentes" to form. Scientists would like to send a lander down to sample surface regions where water wells up through the icy crust.

These areas could allow a robotic probe to sample a proxy for ocean water that lies several kilometres deep.


Details of the penitentes theory were announced as scientists outlined another proposal to explore the jovian moon with robotic spacecraft.


On Earth, these features (so named because of their resemblance to the pointed caps worn by "penitents" in Easter processions around the Spanish-speaking world) form in high altitude regions such as the Andes. Here, the air is both cold and dry, allowing ice to sublimate (turn from a solid into vapour without passing through a liquid phase).


Penitentes begin to form when irregularities in the surface of the snow are enhanced by the Sun's energy. These furrows then act as a trap for solar radiation, and, as they deepen, the tall peaks are left behind.

No comment yet.
Scooped by Dr. Stefan Gruenwald!

DNA reveals giant squid is one single species and had brush with death

DNA reveals giant squid is one single species and had brush with death | Amazing Science |
Genetic uniformity shows legendary kraken to be remarkably vulnerable.


The fearsome sea monster of Greek and Norse tales — and the creature that fought Captain Nemo in 20,000 Leagues Under the Sea — was once driven close to extinction, gene sequencing suggests. The genetic uniformity of giant squid across distant oceans hints at a past evolutionary bottleneck, but also at low resiliency toward future crises.


The finding comes from an analysis of tissue samples from 43 giant squid (Architeuthis spp.) from around the world. The samples came mostly from dead squid that had been found washed up on beaches or floating on the ocean surface, although a few came from animals that were accidentally caught by deep-sea trawlers.


When the researchers looked closely at the mitochondrial DNA of the creatures, they noticed something remarkable. Irrespective of where they came from — be it be it California, Japan, South Africa, New Zealand or somewhere else — the squid were genetically very similar.


In fact, the diversity of Architeuthis is lower than that for any other marine animal, except one — the basking shark Cetorhinus maximus, whose current population is thought to have rebounded from a small number of individuals. At first, says Thomas Gilbert, a geneticist at the University of Copenhagen and an author of the study, “When we found that the global genetic diversity of the giant squid was this low, we figured we had made an error.” But then the team checked their numbers again and saw that they were correct.

No comment yet.
Scooped by Dr. Stefan Gruenwald!

Flash memory chip built out of single-atom-thick components

Flash memory chip built out of single-atom-thick components | Amazing Science |
Graphene and molybdenum disulfide layers make up most of the working parts.


The basic outline of a flash memory device involves two electrodes that feed current through a semiconductor within the device. When a negative voltage is sent across a device from a control electrode, electrons are able to feed into a reservoir that retains the charge; reversing the voltage allows them to escape. The presence of the electrons in the reservoir can be read out by sending current through the semiconductor.


To build a compact version of the device, the authors of the new paper (who are based in Lausanne, Switzerland) started with two sheets of graphene layered on some silicon, separated by a small gap. These served as the electrodes, with the device itself acting as a bridge between them. The next layer on top of that was the semiconductor, formed by a single-molecule-thick sheet of molybdenum disulfide. Above that, a layer of an insulator that allows electrons to tunnel through it separated the conductor from the charge reservoir. To hold the charges, the authors used a few layers of graphene. That was topped by a bit more insulator and another electrode that acted to control the device, setting it to read or erase.


The insulator used in this work wasn't a single atom thick (although insulators of this sort are known) and the graphene charge reservoir was several layers thick, so there were clearly a number of layers involved. But still, this is a very thin device, and can potentially be made even thinner. The manufacturing technique could use some improvements as well, given that one of the steps involved finding individual layers using an optical microscope.


In any case, the devices worked. Applying a positive voltage to the control electrode allowed charge to accumulate in the graphene layers, and its presence could be read out based on the current flowing through the device. Reversing the voltage across the control electrode erased the device. They went through 120 write/erase cycles, and the device still functioned. They also left the device unpowered for a bit, and found that while its storage did decay a bit, it only decayed very slowly. Based on the rate, they expect that, after 10 years, 30 percent of the original charge would still be present.

No comment yet.
Scooped by Dr. Stefan Gruenwald!

NASA using 3D laser printing to create complex rocket parts

NASA using 3D laser printing to create complex rocket parts | Amazing Science |

NASA engineers are using a 3D laser printing system to produce intricate metal parts such as rocket engine components for its next-generationSpace Launch System (SLS). The method called “selective laser melting “ (SLM) promises to streamline fabrication and significantly reduce production costs.


Rocket engines are as complex as precision watches, but watches don’t have to deal with highly corrosive or cryogenic liquids, gases hot enough to melt steel, or destructive stresses and vibrations.


Rocket engines have to do all this the first time they’re used and they have to fit a great deal of gear into a very cramped space. Fabricating the parts for these engines is an exacting, time consuming and expensive task. Since many of their components are very intricate, making them is just the sort of job for 3D printers.

No comment yet.
Scooped by Dr. Stefan Gruenwald!

Pour, Shake and Stir: Rapid Point-Of-Care Testing for Multiple Diseases from a Drop of Blood

Pour, Shake and Stir: Rapid Point-Of-Care Testing for Multiple Diseases from a Drop of Blood | Amazing Science |

A diagnostic “cocktail” containing a single drop of blood, a dribble of water, and a dose of DNA powder with gold particles could mean rapid diagnosis and treatment of the world’s leading diseases in the near future. The cocktail diagnostic is a homegrown brew being developed by University of Toronto’s Institute of Biomaterials and Biomedical Engineering (IBBME) PhD student Kyryl Zagorovsky and Professor Warren Chan that could change the way infectious diseases, from HPV and HIV to malaria, are diagnosed.


Zagorovsky’s rapid diagnostic biosensor will allow technicians to test for multiple diseases at one time with one small sample, and with high accuracy and sensitivity. The biosensor relies upon gold particles in much the same vein as your average pregnancy test. With a pregnancy test, gold particles turn the test window red because the particles are linked with an antigen that detects a certain hormone in the urine of a pregnant woman.


“Gold is the best medium,” explains Chan, “because it’s easy to see. It emits a very intense colour.”


Currently scientists can target the particular disease they are searching for by linking gold particles with DNA strands: when a sample containing the disease gene (ie. Malaria) is present, it clumps the gold particles, turning the sample blue.


Rather than clumping the particles together, Zagorovsky immerses the gold particles in a DNA-based enzyme solution (DNA-zyme) that, when the disease gene is introduced, ‘snip’ the DNA from the gold particles, turning the sample red.


“It’s like a pair of scissors,” Zagorovsky explains, “and the target gene activates the scissors that cut the DNA links holding gold particles together.”

The advantage is that far less of the gene needs to be present for the solution to show noticeable colour changes, amplifying detection. A single DNA-zyme can clip up to 600 “links” between the target genes.


Just a single drop from a biological sample such as saliva or blood can potentially be tested in parallel, so that multiple diseases can be tested for in one sitting.


But the team has also demonstrated that they are able to transform the testing solution into a powder, making it light and far easier to ship than solutions, which degrade over time. Powder can be stored for years at a time, and offers hope that the technology can be developed into efficient, cheap, over-the-counter tests for diseases such as HIV and malaria for developing countries, where access to portable diagnostics is a necessity.

No comment yet.
Rescooped by Dr. Stefan Gruenwald from Longevity science!

Tiny, personal blood testing laboratory gets under your skin

Tiny, personal blood testing laboratory gets under your skin | Amazing Science |

Blood tests usually involve drawing some blood out of the body. Now scientists from the Ecole Polytechnique Fédérale de Lausanne (EPFL) have developed an implant that allows blood to be analyzed from within the body, with results then transmitted wirelessly to a computer.


While still at the experimental stage, the device could make it easier for health care providers to monitor the chronically ill and provide more personalized treatment to cancer patients.



Via Ray and Terry's
No comment yet.
Scooped by Dr. Stefan Gruenwald!

Receptor for Tasting Fat is CD36

Receptor for Tasting Fat is CD36 | Amazing Science |
For the first time, a team of scientists at Washington University School of Medicine has identified a human receptor that can taste fat.


CD36 is a membrane protein found on the surface of many cell types in humans, mice, rats and many vertebrate animals. The findings also suggest that variations in the CD36 gene can make people more or less sensitive to the taste of fat.


“The ultimate goal is to understand how our perception of fat in food might influence what foods we eat and the quantities of fat that we consume,” said Dr. Nada Abumrad, senior investigator and the Dr. Robert A. Atkins Professor of Medicine and Obesity Research.


“In this study, we’ve found one potential reason for individual variability in how people sense fat. It may be, as was shown recently, that as people consume more fat, they become less sensitive to it, requiring more intake for the same satisfaction. What we will need to determine in the future is whether our ability to detect fat in foods influences our fat intake, which clearly would have an impact on obesity.”


The CD36 discovery follows research that had identified a role for the gene in rats and mice. Scientists had learned that when animals are genetically engineered without a working CD36 gene, they no longer display a preference for fatty foods. In addition, animals that can’t make the CD36 protein have difficulty digesting fat.


Up to 20 percent of people are believed to have the variant in the CD36 gene that is associated with making significantly less CD36 protein. That, in turn, could mean they are less sensitive to the presence of fat in food.


Dr. Abumrad was the first to identify CD36 as the protein that facilitates the uptake of fatty acids. She explained that better understanding of how the protein works in people could be important in the fight against obesity.

“Diet can affect sensitivity to fat, and in animals, diet also influences the amount of CD36 that’s made,” added Dr. Pepino. “If we follow the results in animals, a high-fat diet would lead to less production of CD36, and that, in turn, could make a person less sensitive to fat. From our results in this study, we would hypothesize that people with obesity may make less of the CD36 protein. So it would seem logical that the amounts of the protein we make can be modified, both by a person’s genetics and by the diet they eat.”

No comment yet.
Scooped by Dr. Stefan Gruenwald!

Modified Cold Sore Virus Shrinks Melanoma Tumors, Amgen Says

Modified Cold Sore Virus Shrinks Melanoma Tumors, Amgen Says | Amazing Science |

A genetically modified version of herpes simplex virus type 1, the same virus that causes cold sores, shrank tumors of the deadly skin cancer melanoma in a clinical trial, according to Amgen, which is developing the experimental cancer treatment.


Patients in the trial were in the late stages of the disease, and were either being treated with a drug called GM-CSF or the new virus. Sixteen percent of the patients in the group that got the virus, known as talimogene laherparepvec, saw their tumors shrink completely or partially for at least six months. That compares to two percent of the control group. There was a trend toward the virus helping patients live longer, but the difference is not yet statistically significant.Amgen says that it may become so later this year, and those results are likely to be far more important in determining the future of the treatment.


Amgen purchased the company that developed the virus, Biovex, in 2011 for $425 million in cash and a commitment to pay up to $575 million if Biovex’s medicines hit certain milestones. If the Biovex anti-cancer virus is indeed a potent cancer fighter, it could help get investors excited about Amgen. It might also benefit Merck, because Amgen’s former research chief, Roger Perlmutter, has just agreed to take over running the research labs there, and this might reflect on his ability to make smart acquisitions.


No comment yet.
Scooped by Dr. Stefan Gruenwald!

97% of family doctors in the UK admitted to giving placebos to patients at least once

97% of family doctors in the UK admitted to giving placebos to patients at least once | Amazing Science |

In a poll, 97% of 783 GPs admitted that they had recommended a sugar pill or a treatment with no established efficacy for the ailment their patient came in with.


The Royal College of GPs says there is a place for placebos in medicine.

But they warn that some sham treatments may be inappropriate and could cause side effects or issues such as drug resistance.


For example, one of the placebo treatments identified in the study was antibiotics for suspected viral infections.


This is not about doctors deceiving patients”. Antibiotics are powerless against viruses and doctors are told not to use them.


About one in 10 of the GPs in the study said they had given a patient a sugar pill or an injection of salty water rather than a real medicine at some time in their career. One in 100 of them said they did this at least once a week.


Almost all of the GPs said they had provided patients with treatments, like supplements, probiotics and complementary medicines, that were unproven for their medical condition. Three-quarters said they offered unproven treatments on a daily or weekly basis.


Dr. Jeremy Howick, co-author of the study that was carried out by the University of Oxford and the University of Southampton, said: "This is not about doctors deceiving patients. "The study shows that placebo use is widespread in the UK, and doctors clearly believe that placebos can help patients."


The GPs in the study said they used placebos either because patients requested treatment or to reassure patients. Half said they told their patients that the therapy had helped other patients without specifically telling them that they were prescribing a placebo.


Dr Clare Gerada, chairwoman of the Royal College of GPs, said it was perfectly acceptable to use a placebo as long as it did not cause harm and was not expensive. "Lots of doctors use them and they can help people.

"If you think about it, a kiss on the cheek when you fall over is a placebo.

"But there are risks. Not all of the placebo treatments that the researchers looked at in this study are inert. If you take too many vitamins, for example, some can cause harm."


She said fobbing off patients with an ineffectual treatment was never acceptable. "But admitting to your patient that you do not know exactly what is going on, but that a therapy might help is."

No comment yet.
Scooped by Dr. Stefan Gruenwald!

Origami sphere: DNA folding takes a fresh direction

Origami sphere: DNA folding takes a fresh direction | Amazing Science |

The intricate art of DNA origami has been given a fresh twist. Researchers at Arizona State University in Tempe have managed to coerce a single strand of DNA to fold back on itself to form an array of two- and three-dimensional nanostructures.


DNA origami involves using scaffolding to guide a single strand of DNA as it folds up to form a shape. The Arizona team, led by Hao Yan, managed to create more intricate shapes than have been possible so far, by using scaffolding made up of cross-like structures of two DNA strands nearly at right angles to each other.


Similar cross-shaped structures, called Holliday junctions, are not new. But it had been thought impossible to link them together to make a stable scaffold because the charge of the DNA molecules was always mismatched.


Yan and his team overcame this problem by tweaking the way they assembled their scaffold so that the junctions became slightly ‘twisted’. The result was that junctions could link together to form a waffle-like gridiron structure that is “surprisingly very stable”, Yan says.

Using this, the team was able to guide the formation of not only two-dimensional DNA structures but also three-dimensional spheres and screw-like shapes. The scaffold and the various structures it can produce are published in Science today.


Yan hopes that DNA origami can now become more useful, perhaps building three-dimensional ‘cages’ to hold drugs and so deliver them to the specific place they are needed in the body.

No comment yet.
Scooped by Dr. Stefan Gruenwald!

US report: How to cut U.S. gasoline use in half by 2030

US report: How to cut U.S. gasoline use in half by 2030 | Amazing Science |
A new report from the National Academy of Sciences shows how it can be done, but no single technology or policy will get us there.


Those are audacious goals. But if the United States ever plans to deal seriously with climate change, the transportation sector will have to change drastically. And the National Academy of Sciences report concludes that no one single policy or technology will do the trick.


Case in point: In the past few years, the Obama administration has enacted a series of ambitious corporate average fuel economy  standards that will require new cars to get around 54.5 miles per gallon by 2025. (That will translate into about 35.4 miles per gallon on the road.) That sounds impressive, but the NAS study concludes that current standards aren’t enough to hit even that 2030 goal for oil use.


In fact, the report argues, it’s tough to find any single technology that can cut oil use in half by 2030 on its own. Making conventional cars more efficient won’t do it. A major push on electric vehicles won’t do it. The only things likely to work are a massive switch over to natural-gas vehicles (which would, in turn, make it much harder to hit the greenhouse-gas goals) or a combination of efficiency, electric vehicles, and advanced biofuels.


What the NAS is doing here is estimating the impact of each technology “if it is pursued vigorously.” And it found that each technology, on its own, has some promising upsides and some limitations. Better efficiency, for instance: The report found that there’s enormous potential to make conventional gasoline vehicles more efficient, from engine and drivetrain improvements to lighter vehicles. Over the past few  years, automakers have started adopting many of these tactics, such as gasoline direct injection. The NAS report estimates that conventional cars could realistically average 74 miles per gallon in 2050 and hybrids 94 mpg.

No comment yet.
Scooped by Dr. Stefan Gruenwald!

Controlled double-slit electron diffraction used to demonstrate Feynman's original thought experiment

Controlled double-slit electron diffraction used to demonstrate Feynman's original thought experiment | Amazing Science |
Double-slit diffraction is a corner stone of quantum mechanics. It illustrates key features of quantum mechanics: interference and the particle-wave duality of matter. In 1965, Richard Feynman presented a thought experiment to show these features.


Richard Feynman described electron diffraction as a phenomenon 'which has in it the heart of quantum mechanics. In reality, it contains the only mystery'. He went on to describe a thought experiment for which he stated 'that you should not try to set up' because 'the apparatus would have to be made on an impossibly small scale to show the effects we are interested in'. He used these effects to help illustrate the phenomena of wave–particle duality, which is a postulate that all particles exhibit both wave and particle properties. The effects he described were: the relations between electron probability distributions from single- and double-slits, and observation of single particle diffraction. In this paper we report both control over the individual slits to observe probability distributions from both single- and double-slits, and the build-up of a diffraction pattern at single electron detection rates to achieve the full realization of Feynman's thought experiment. We use the term build-up to refer to the measurement of the cumulative spatial detection pattern as a function of time.


The general perception is that the electron double-slit experiment has already been performed. This is true in the sense that Jönsson demonstrated diffraction from single, double, and multiple (up to five) micro-slits, but he could not observe single particle diffraction, nor close individual slits. In two separate landmark experiments, individual electron detection was used to produce interference patterns; however, biprisms were used instead of double-slits. First, Pozzi recorded the interference patterns at varying electron beam densities. Then, Tonomura recorded the positions of individual electron detection events and used them to produce the well known build-up of an interference pattern. It is interesting to point out that the build up of a double-slit diffraction pattern has been called 'The most beautiful experiment in physics', while the build-up for a true double-slit has, up to now, never been reported.


More recently, electron diffraction was demonstrated with single- and double-slits using focused ion beam (FIB) milled nano-slits. In addition, one single slit in a double-slit was closed by FIB induced deposition. This process is not reversible, so observation of the electron probability distribution through both single-slits could not be done. Also, using a fast-readout pixel detector, electrons were recorded one at a time and stacked into a final diffraction pattern, but intermediate spatial patterns were not reported.


Feynman's original thought experiment contained two parts. The first involved observing probability distributions in three scenarios: electrons traveling through slit 1 with slit 2 closed (P1); electrons traveling through slit 2 with slit 1 closed (P2); and electrons traveling through both slits (P12). These scenarios illustrate the quantum mechanical superposition principle, i.e. the wave properties, and can be demonstrated with control of the slits (see Figure). The second part of the thought experiment was the observation of individual electrons associated with detection 'clicks'. This illustrates that a quantum mechanical electron wave cannot be thought of as comprising multiple electrons, i.e. the particle properties, which can be demonstrated with the build-up of the diffraction pattern.

No comment yet.
Scooped by Dr. Stefan Gruenwald!

NASA: Herschel Discovers Some of the Youngest Stars Ever Seen

NASA: Herschel Discovers Some of the Youngest Stars Ever Seen | Amazing Science |
Astronomers have found some of the youngest stars ever seen, thanks to the Herschel space observatory, a European Space Agency mission with important NASA contributions.


stronomers have found some of the youngest stars ever seen, thanks to the Herschel space observatory, a European Space Agency mission with important NASA contributions. Observations from NASA's Spitzer Space Telescope and the Atacama Pathfinder Experiment (APEX) telescope in Chile, a collaboration involving the Max Planck Institute for Radio Astronomy in Germany, the Onsala Space Observatory in Sweden, and the European Southern Observatory in Germany, contributed to the findings.


Dense envelopes of gas and dust surround the fledging stars known as protostars, making their detection difficult. The 15 newly observed protostars turned up by surprise in a survey of the biggest site of star formation near our solar system, located in the constellation Orion. The discovery gives scientists a peek into one of the earliest and least understood phases of star formation.


"Herschel has revealed the largest ensemble of such young stars in a single star-forming region," said Amelia Stutz, lead author of a paper to be published in The Astrophysical Journal and a postdoctoral researcher at the Max Planck Institute for Astronomy in Heidelberg, Germany. "With these results, we are getting closer to witnessing the moment when a star begins to form."


Of NASA's 15 newly discovered protostars, 11 possess very red colors, meaning their light output trends toward the low-energy end of the electromagnetic spectrum. This output indicates the stars are still embedded deeply in a gaseous envelope, meaning they are very young. An additional seven protostars previously seen by Spitzer share this characteristic.


Together, these 18 budding stars comprise only five percent of the protostars and candidate protostars observed in Orion. That figure implies the very youngest stars spend perhaps 25,000 years in this phase of their development, a mere blink of an eye considering a star like our sun lives for about 10 billion years.


Researchers hope to document chronologically each stage of a star's development rather like a family album, from before birth to early infancy, when planets also take shape.


"With these recent findings, we add an important missing photo to the family album of stellar development," said Glenn Wahlgren, Herschel Program Scientist at NASA Headquarters in Washington. "Herschel has allowed us to study stars in their infancy."


Herschel is a European Space Agency mission, with science instruments provided by a consortia of European institutes with important participation by NASA. NASA's Herschel Project Office is based at the agency's Jet Propulsion Laboratory in Pasadena, Calif. JPL is a division of the California Institute of Technology, Pasadena.

No comment yet.
Scooped by Dr. Stefan Gruenwald!

When mind is at rest, brain sends backward signals to clear useless old information

When mind is at rest, brain sends backward signals to clear useless old information | Amazing Science |

When the mind is at rest, the electrical signals by which brain cells communicate appear to travel in reverse, wiping out unimportant information in the process, but sensitizing the cells for future sensory learning, according to a study of rats conducted by researchers at the National Institutes of Health.


The finding has implications not only for studies seeking to help people learn more efficiently, but also for attempts to understand and treat post-traumatic stress disorder―in which the mind has difficulty moving beyond a disturbing experience.


During waking hours, brain cells, or neurons, communicate via high-speed electrical signals that travel the length of the cell. These communications are the foundation for learning. As learning progresses, these signals travel across groups of neurons with increasing rapidity, forming circuits that work together to recall a memory.


It was previously known that, during sleep, these impulses were reversed, arising from waves of electrical activity originating deep within the brain. In the current study, the researchers found that these reverse signals weakened circuits formed during waking hours, apparently so that unimportant information could be erased from the brain. But the reverse signals also appeared to prime the brain to relearn at least some of the forgotten information. If the animals encountered the same information upon awakening, the circuits re-formed much more rapidly than when they originally encountered the information.


“The brain doesn’t store all the information it encounters, so there must be a mechanism for discarding what isn’t important,” said senior author R. Douglas Fields, Ph.D., head of the Section on Nervous System Development and Plasticity at the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), the NIH institute where the research was conducted. “These reverse brain signals appear to be the mechanism by which the brain clears itself of unimportant information.”

No comment yet.
Scooped by Dr. Stefan Gruenwald!

Scientists discover new species of crocodile newt in Vietnam

Scientists discover new species of crocodile newt in Vietnam | Amazing Science |

Researchers have discovered a new species of Vietnamese salamander that looks like it was birthed from an abyssal volcano. Found tucked away in Tokyo's National Museum of Nature and Science, the scientists described the species in the new edition ofCurrent Herpetology. Coal-black with orange-tinted toes, the new crocodile newt (in the genus Tylototriton) was determined to be a new species when it showed morphological and genetic differences from near relatives. Despite its remarkable appearance, the researchers say these are typical colors for crocodile newts.

No comment yet.