Researchers at Oregon Health & Science University – OHSU – have made a significant breakthrough in efforts to develop human stem cell therapies that may be used to combat numerous devastating diseases. For the first time, scientists have successfully derived embryonic stem cells by reprogramming of genetic material from skin cells while studying rhesus macaque monkeys. The breakthrough follows several previously unsuccessful attempts by the OHSU-based team and other scientific teams worldwide.

“Many scientists believe that embryonic stem cells hold great promise for treating a variety of diseases including Parkinson’s disease, multiple sclerosis, cardiac disease and spinal cord injuries,” explained Shoukhrat Mitalipov, Ph.D., director of the OHSU-based research team. “Using our advanced methods, it is conceivable that years from now, patients could receive therapeutic embryonic stem cells developed from their very own cells meaning that there would be no concerns about transplant rejection. Another noteworthy aspect of this research is that it does not involve the use of fertilized embryos, a topic which has been the source of a significant ethical debate in this country. ”

Neverthless “it’s a matter of time before they produce a cloned monkey,” said Jose Cibelli, a cloning expert at Michigan State University, who wasn’t involved in the study. It also means, he added, “that they are one step closer to where the efficiency is high enough that someone is willing to try” to clone a person.

The results of the work were released online by the scientific journal Nature.
Source: http://www.ohsu.edu

Researchers from Brigham and Women’s Hospital (BWH) are the first to report that synthetic silicate nanoplatelets (also known as layered clay) can induce stem cells to become bone cells without the need of additional bone-inducing factors. Synthetic silicates are made up of simple or complex salts of silicic acids, and have been used extensively for various commercial and industrial applications, such as food additives, glass and ceramic filler materials, and anti-caking agents.

“With an aging population in the US, injuries and degenerative conditions are subsequently on the rise,” said Ali Khademhosseini, PhD, BWH Division of Biomedical Engineering, senior study author. “As a result, there is an increased demand for therapies that can repair damaged tissues. In particular, there is a great need for new materials that can direct stem cell differentiation and facilitate functional tissue formation. Silicate nanoplatelets have the potential to address this need in medicine and biotechnology.”
The study has been published online May 13, 2013 in Advanced Materials.

Source: http://www.brighamandwomens.org/

Researchers at Queen’s University Belfast have devised a ‘magic bullet’ nanomedicine which could become the first effective treatment for Acute Lung Injury or ALI, a condition affecting 20 per cent of all patients in intensive care. Many with the condition die as a result of lung failure.
ALI patients can become critically ill and develop problems with breathing when their lungs become inflamed and fill with fluid. The new drug, a nanoparticle, measuring around one billionth of a metre. could revolutionise clinical management of patients in intensive care units. The patient can inhale it, taking the drug directly into the lungs and to the point of inflammation. Current treatments are unable to target directly the inflammation and can result in unpleasant side effects.

“Nanoparticles are perhaps one of the most exciting new approaches to drug development. Most research in the area focuses on how the delivery of drugs to the disease site can be improved in these minute carriers. Our own research in this area focuses on how nanoparticles interact with cells and how this can be exploited to produce therapeutic effects both in respiratory disease and cancer.”, said Professor Chris Scott from the School of Pharmacy, who is leading the research.

Source: http://www.qub.ac.uk/

Northwestern University scientists have struck gold in the laboratory. They have discovered an inexpensive and environmentally benign method that uses simple cornstarch – instead of cyanide — to isolate gold from raw materials in a selective manner. This green method extracts gold from crude sources and leaves behind other metals that are often found mixed together with the crude gold. The new process also can be used to extract gold from consumer electronic waste. Current methods for gold recovery involve the use of highly poisonous cyanides, often leading to contamination of the environment. Nearly all gold-mining companies use this toxic gold leaching process to sequester the precious metal.

A modern day gold rush! A new method developed at Northwestern bypasses the use of toxic cyanide for gold purification by using an eco-friendly sugar (cyclodextrin) derived from starch
“The elimination of cyanide from the gold industry is of the utmost importance environmentally,” said Sir Fraser Stoddart, the Board of Trustees Professor of Chemistry in the Weinberg College of Arts and Sciences. “We have replaced nasty reagents with a cheap, biologically friendly material derived from starch.”
Source: http://www.northwestern.edu/

Using the SIV (Simian Immunodeficiency Virus) model in Chinese macaques, a research group headed by Jean-Marie Andrieu from University PARIS V – France – with Wei Lu from University of Montpellier were able to suppress the initial activation of SIV- positive CD4+ T-lymphocytes in vivo which is the crucial step that allows SIV to initiate replication and to establish infection. They used an oral vaccine made of inactivated SIVmac239 associated with a common commensal bacterium of the digestive tract known as Lactobacillus plantarum which is known to induce immunological tolerance to foreign antigens.
In contrast to what happens with all anti-viral vaccines, this oral
tolerogenic vaccine elicited neither anti-SIV antibodies nor cytotoxic
T-lymphocytes but induced instead a previously unrecognized class of
SIV- specific, non-cytolytic CD8+ T-regulatory cells which prevented SIV+ CD4+ T-cell activation and suppressed SIV replication.
By blocking SIV reverse transcription in CD4+ T-cells, the initial burst of virus replication was prevented and the vaccinated macaques were protected from infection. Of the 16 vaccinated macaques that were challenged intra-rectally 3 to 14 months later with the homologous SIV strain as well as with the heterologous strainSIV-B670, 15 were solidly protected from SIV challenge.

Since CD4+ T-cell activation
drives both the initial SIV and HIV-1 replication in macaques and
humans respectively, it is plausible that such a tolerogenic vaccine may
also be effective against HIV-1 in humans and this will be certainly be
investigated in the near future, either as a preventive or therapeutic
vaccine..

Test on humans will start by the end of this year.
Source: http://www.parisdescartes.fr/
In english: Ask for PDF document at:
Alice Tschudy
Press Officer
Université Paris Descartes
+33 1 76 53 18 63 / 17 98
presse@parisdescartes.fr

Take a swab of saliva from your mouth and within minutes your DNA could be ready for analysis and genome sequencing with the help of a new device. Now University of Washington engineers and NanoFacture, a Bellevue, Wash., company, have created a device that can extract human DNA from fluid samples in a simpler, more efficient and environmentally friendly way than conventional methods. The device will give hospitals and research labs a much easier way to separate DNA from human fluid samples, which will help with genome sequencing, disease diagnosis and forensic investigations.

Hand-held device for extracting DNA
“It’s very complex to extract DNA,” said Jae-Hyun Chung, a UW associate professor of mechanical engineering who led the research. “When you think of the current procedure, the equivalent is like collecting human hairs using a construction crane.”
The small, box-shaped kit now is ready for manufacturing, then eventual distribution to hospitals and clinics.

Source:http://www.washington.edu/

In a promising development for diabetes treatment, researchers have developed a network of nanoscale particles that can be injected into the body and release insulin when blood-sugar levels rise, maintaining normal blood sugar levels for more than a week in animal-based laboratory tests. The work was done by researchers at North Carolina State University, the University of North Carolina at Chapel Hill, the Massachusetts Institute of Technology and Children’s Hospital Boston.

The nano-network releases insulin in response to changes in blood sugar

“We’ve created a ‘smart’ system that is injected into the body and responds to changes in blood sugar by releasing insulin, effectively controlling blood-sugar levels,” says Dr. Zhen Gu, lead author of a paper describing the work and an assistant professor in the joint biomedical engineering program at NC State and UNC Chapel Hill. “We’ve tested the technology in mice, and one injection was able to maintain blood sugar levels in the normal range for up to 10 days.”
Source: http://news.ncsu.edu/

Scientists at Princeton University used off-the-shelf printing tools to create a functional ear that can “hear” radio frequencies far beyond the range of normal human capability. The researchers’ primary purpose was to explore an efficient and versatile means to merge electronics with tissue. The scientists used 3D printing of cells and nanoparticles followed by cell culture to combine a small coil antenna with cartilage, creating what they term a bionic ear.

“In general, there are mechanical and thermal challenges with interfacing electronic materials with biological materials,” said Michael McAlpine, an assistant professor of mechanical and aerospace engineering at Princeton and the lead researcher. “Previously, researchers have suggested some strategies to tailor the electronics so that this merger is less awkward. That typically happens between a 2D sheet of electronics and a surface of the tissue. However, our work suggests a new approach — to build and grow the biology up with the electronics synergistically and in a 3D interwoven format.”

Source: http://www.eurekalert.org/

University of Florida researchers have developed a “DNA nanotrain” that fast-tracks its payload of cancer-fighting drugs and bioimaging agents to tumor cells deep within the body. The nanotrain’s ability to cost-effectively deliver high doses of drugs to precisely targeted cancers and other medical maladies without leaving behind toxic nano-clutter has been the elusive Holy Grail for scientists studying the teeny-tiny world of DNA nanotechnology.

“Most nanotechnology relies on a nanoparticle approach, and the particles are made of inorganic materials; after they’ve been used as a carrier for the drug, they’ll be left inside the body,” said the study’s lead investigator, Weihong Tan, a UF distinguished professor of chemistry, professor of physiology and functional genomics, and a member of the UF Shands Cancer Center and the UF Genetics Institute. “Compared to existing nanostructures, our nanotrain is easier and cheaper to make, is highly specific to cancer cells, has a lot of drug-loading power and is very much biocompatible.”

DNA nanotechnology holds great promise as a new way to deliver chemotherapy directly to cancer cells, but until now, scientists have not been able to direct nanotherapies to consistently differentiate cancer cells from healthy ones. Other limiting factors include high costs, too-small amounts of drugs delivered and potential toxic side effects.
Source: http://news.ufl.edu/

Researchers at Northeastern University in Boston have developed a gene therapy approach that may one day stop Parkinson’s disease (PD) in it tracks, preventing disease progression and reversing its symptoms. Each year, 60,000 adults are newly diag­nosed with Parkinson’s dis­ease, a neu­rode­gen­er­a­tive dis­order that causes a slew of symp­toms, including tremors, slowed move­ments, and changes in speech. The drugs cur­rently avail­able to treat PD patients help them regain some of the motor con­trol lost through the dis­ease, but don’t treat the under­lying cause, said Bar­bara Waszczak, a pro­fessor of phar­ma­ceu­tical sci­ences in the Bouvé Col­lege of Health Sci­ences.

“Parkinson’s is caused by the death of dopamine neu­rons in a key motor area of the brain called the sub­stantia nigra,” said Waszczak. If you want to treat PD at its roots, she added, then you have to stop the death of these neural cells. In research reported ear­lier this week at the Exper­i­mental Biology 2013 con­fer­ence in Boston, Waszczak and grad­uate stu­dent Brendan Harmon pro­posed a treat­ment approach that does exactly that. What’s more, the method is simple and easy to use.“If we can get at it in the early stages of the dis­ease, when patients are just starting to develop symp­toms, then we might be able to stop the dis­ease from get­ting worse or at least delay the onset of severe symp­toms,” Waszczak explained.

Source: http://www.northeastern.edu/
AND
http://www.eurekalert.org/

An Indiana University School of Medicine breast cancer surgeon is pursuing research that will utilize glass, gold, nanotechnology and Greek mythology hoping to vanquish breast cancer that has metastasized to the brain. Susan E. Clare, M.D., Ph.D., associate professor of surgery at the IU School of Medicine, is the initiating principal investigator for a $573,000 Department of Defense grant that will allow her to explore a new approach to delivering therapy to brain metastases from primary breast cancer. As did the Greeks of old, Dr. Clare hopes to covertly deliver “warriors” to the enemy stronghold, in this case a metastatic brain tumor. Her research will explore using a cell from the body’s immune system to deliver chemotherapy directly to the brain metastases. The drug or other therapeutic is attached to the nanospheres, which are carried within the immune cell, much as soldiers were carried within the Trojan Horse. The immune cells travel in the bloodstream and release the drug when it has reached the tumor site.

“The problem for almost all drugs, and HER2-targeted drugs are no exception, is that the blood-brain barrier is a significant impediment to delivering therapies in concentrations that can be effective,” Dr. Clare said.

That biological issue caused Dr. Clare to explore other methods of delivering drugs to metastatic brain tumors. Using nanoparticles called “nanoshells,” developed by Naomi J. Halas, Ph.D., D.Sc., director of the Laboratory for Nanophotonics at Rice University, Dr. Clare hopes to target the brain tumors with lapatinib at a dose sufficient to shut down the signaling pathway needed for the cancer cells to proliferate.

Source: http://news.medicine.iu.edu

UCLA researchers led by Professor Dean Ho from the Jane and Jerry Weintraub Center for Reconstructive Biotechnology, have developed a potentially more effective treatment for breast cancer. Doctors have begun to categorize breast cancers into four main groups according to the genetic makeup of the cancer cells. Which category a cancer falls into generally determines the best method of treatment. But cancers in one of the four groups — called “basal-like” or “triple-negative” breast cancer (TNBC) — have been particularly tricky to treat because they usually don’t respond to the “receptor-targeted” treatments that are often effective in treating other types of breast cancer. TNBC tends to be more aggressive than the other types and more likely to recur, and can also have a higher mortality rate. Using nanodiamonds between 4 and 6 nanometers in diameter and shaped like tiny soccer balls, the researchers form clusters following drug binding that have the ability to precisely deliver cancer drugs to tumors, significantly improving the drugs’ desired effect. In the UCLA study, the nanodiamond delivery system has been able to home in on tumor masses in mice with triple negative breast cancer.

“This study demonstrates the versatility of the nanodiamond as a targeted drug-delivery agent to a tumor site,” said Ho, who is also a member of the California NanoSystems Institute at UCLA, UCLA’s Jonsson Comprehensive Cancer Center and the UCLA Department of Bioengineering. “The agent we’ve developed reduces the toxic side effects that are associated with treatment and mediates significant reductions in tumor size.”
Findings from the study are published online April 15 in the peer-reviewed journal Advanced Materials.
Source: http://newsroom.ucla.edu/

Engineers at the University of California, San Diego have invented a “nanosponge” capable of safely removing a broad class of dangerous toxins from the bloodstream – including toxins produced by MRSA, E. coli, poisonous snakes and bees. These nanosponges, which thus far have been studied in mice, can neutralize “pore-forming toxins,” which destroy cells by poking holes in their cell membranes. Unlike other anti-toxin platforms that need to be custom synthesized for individual toxin type, the nanosponges can absorb different pore-forming toxins regardless of their molecular structures. In a study against alpha-haemolysin toxin from MRSA, pre-innoculation with nanosponges enabled 89 percent of mice to survive lethal doses. Administering nanosponges after the lethal dose led to 44 percent survival. Methicillin-resistant Staphylococcus aureus (MRSA) infection is caused by a strain of staph bacteria that’s become resistant to the antibiotics commonly used to treat ordinary staph infections.

“One of the first applications we are aiming for would be an anti-virulence treatment for MRSA. That’s why we studied one of the most virulent toxins from MRSA in our experiments,” said “Jack” Che-Ming Hu, the first author on the paper. The team, led by nanoengineers at the UC San Diego Jacobs School of Engineering, published the findings in Nature Nanotechnology April 14.
Source: http://www.eurekalert.org/

Researchers at the Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) at Trinity College in Dublin – Ireland – are pursuing a new nanomaterial-based approach to neural networks that combines work in nanowires and memristors (2-terminal memory devices based on resistance switching effects). They develop a new computing paradigm that mimics the neural networks of the human brain. Both nanowires and memristors are part of the history of research into neural networks and artificial intelligence (AI). Researchers have been investigating the use of nanowires in building electronic meshes on which nerve tissues can be grown; the mesh, they hope, could link nerve cells with electronics. And almost from the time memristors were first isolated and characterized, researchers have been looking at using them in chips that would lead to artificial intelligence.
Professor John Boland, director of CRANN, and his colleagues will be using the research grant to build on their previous work. They already discovered that when electricity—or other stimuli such as chemicals or light—is applied to a random network of nanowires, it generates a chemical reactions at the junctions where the nanowires cross over each other.

This phenomenon is similar to the way the brain works, in that there are bundles of nerves that cross over one another, forming junctions. Over time, the human brain begins to learn which of these junctions is important and discards the rest.
Source: http://www.tcd.ie/

Rice University researchers have found an unexpected link between a protein that triggers the formation of blood clots and other proteins that are essential for the body’s immune system. The find could lead to new treatments for thousands of patients who suffer from inflammatory diseases and disorders that cause abnormal blood clotting.

“This link opens the door for studying severe, debilitating inflammatory disorders where the disease mechanism is still poorly understood, including lupus, rheumatoid arthritis, regional ileitis and ulcerative colitis, as well as age-related macular degeneration,” said study co-author Dr. Joel Moake, a hematologist and senior research scientist in bioengineering at Rice. “There’s clinical evidence that clotting and inflammation are somehow linked in many patients, even in the absence of an infection. This linkage could help explain some of the clinical cases that have long baffled physicians.”
The research is available online in the journal PLOS ONE.

Source: http://news.rice.edu/

Researchers in the Sheffield Centre for Robotics, jointly established by the University of Sheffield and Sheffield Hallam University – United Kingdom -, have been working to program a group of 40 robots, and say the ability to control robot swarms could prove hugely beneficial in a range of contexts, from military to medical.The researchers have demonstrated that the swarm can carry out simple fetching and carrying tasks, by grouping around an object and working together to push it across a surface.The robots can also group themselves together into a single cluster after being scattered across a room, and organize themselves by order of priority. Dr Roderich Gross, head of the Natural Robotics Lab, in the Department of Automatic Control and Systems Engineering at the University of Sheffield, says swarming robots could have important roles to play in the future of micromedicine, as ‘nanobots’ are developed for non-invasive treatment of humans.

“We are developing Artificial Intelligence to control robots in a variety of ways. The key is to work out what is the minimum amount of information needed by the robot to accomplish its task. That’s important because it means the robot may not need any memory, and possibly not even a processing unit, so this technology could work for nanoscale robots, for example in medical applications.” Dr Gross said.

Source: http://www.sheffield.ac.uk/

Early diagnosis is critical in treating Lyme disease. However, nearly one quarter of Lyme disease patients are initially misdiagnosed because currently available serological tests have poor sensitivity and specificity during the early stages of infection. Misdiagnosed patients may go untreated and thus progress to late-stage Lyme disease, where they face longer and more invasive treatments, as well as persistent symptoms. A nanotechnology-inspired technique developed by researchers at the University of Pennsylvania may lead to diagnostics that can detect the organism itself.

An illustration of a Lyme antibody attached to a carbon nanotube
Lyme disease is an infection transmitted by the bite of ticks carrying the spiral-shaped bacterium Borrelia burgdorferi. The disease was named for Lyme, Connecticut, the town where it was first diagnosed in 1975 after a puzzling outbreak of arthritis. The organism was named for its discoverer, Willy Burgdorfer. The effects of this disease can be long-term and disabling unless it is recognized and treated properly with antibiotics.

Source: http://www.upenn.edu/

A research team lead by Dr Peixuan Guo from the University of Kentucky (USA) have cracked a 35-year-old mystery about the workings of the natural motors that are serving as models for development of a futuristic genre of synthetic nanomotors that pump therapeutic DNA, RNA or drugs into individual diseased cells.

The importance of nanomotors in nanotechnology is akin to that of mechanical engines to daily life. The AAA+ superfamily is a class of nanomotors performing various functions. Their hexagonal arrangement facilitates bottom-up assembly for stable structures. Bacteriophage phi29 DNA-translocation motor contains three co-axial rings and viral DNA-packaging motor has been believed to be a rotational machine. However, the researchers found a revolution mechanism without rotation. By analogy, the earth revolves around the sun while rotating on its own axis.
Click here to enjoy the video

Source University of Kentucky: http://nanobio.uky.edu/
AND
ACS Nano: http://pubs.acs.org

The promise of repairing damaged hearts through regenerative medicine — infusing stem cells into the heart in the hope that these cells will replace worn out or damaged tissue — has yet to meet with clinical success. But a highly sensitive visualization technique developed by Stanford University School of Medicine scientists may help speed that promise’s realization.

“All stem cell researchers want to get the cells to the target site, but up until now they’ve had to shoot blindly,” said Gambhir, who is also the Virginia and D.K. Ludwig Professor in Cancer Research and director of the Molecular Imaging Program at Stanford. “With this new technology, they wouldn’t have to. For the first time, they would be able to observe in real time exactly where the stem cells they’ve injected are going and monitor them afterward. If you inject stem cells into a person and don’t see improvement, this technique could help you figure out why and tweak your approach to make the therapy better.”

Source: http://med.stanford.edu/

A multicenter team of researchers has developed biodegradable nanoparticles that are capable of delivering inflammation-resolving drugs to sites of tissue injury. The nanoparticles, which were successfully tested in mice, have potential for the treatment of a wide array of diseases characterized by excessive inflammation, such as atherosclerosis. The study was published today in the online edition of the Proceedings of the National Academies of Science. Particpate scientists at Columbia University Medical Center (CUMC), Brigham and Women’s Hospital (BWH), Mount Sinai School of Medicine, and Massachusetts Institute of Technology.

Collagen IV-targeted polymeric nanoparticles (shown in pink) are home to injured tissue, post-injection, in the blood.
“A variety of medications can be used to control inflammation. Such treatments, however, usually have significant side effects and dampen the positive aspects of the inflammatory response,” said co-senior author Ira Tabas, MD, PhD,at CUMC.

Source: http://www.cumc.columbia.edu/
AND
http://www.eurekalert.org/

Prof. Roy Bar-Ziv and his research team in the Weizmann Institute’s Materials and Interfaces Department – Israel – recently have created a two-dimensional, cell-like system on a glass chip. This system, composed of some of the basic biological molecules found in cells – DNA, RNA, proteins – carried out one of the central functions of a living cell: gene expression, the process by which the information stored in the genes is translated into proteins. More than that, it enabled the scientists, led by research student Yael Heprotein yman, to obtain “snapshots” of this process in nanoscale resolution. The system, consisting of glass chips that are only 8 nanometers thick, is based on an earlier one designed in Bar-Ziv’s lab by Dr. Shirley Daube and former student Dr. Amnon Buxboim. After being coated in a light-sensitive substance, the chips are irradiated with focused beams of ultraviolet light, which enables the biological molecules to bind to the substance in the irradiated areas. In this way, the scientists could precisely place DNA molecules encoding a protein marked with a green fluorescent marker in one area of the chip and antibodies that “trap” the colored proteins in an abutting area.

Protein interaction on a chip: Red proteins concentrated more on the right, farther from the chip-bound genes, while green proteins are more highly concentrated on the left, closer to the genes that encode them

Source: http://wis-wander.weizmann.ac.il/

Nanoparticles carrying a toxin found in bee venom can destroy human immunodeficiency virus (HIV) while leaving surrounding cells unharmed, researchers at Washington University School of Medicine in St. Louis have shown. The finding is an important step toward developing a vaginal gel that may prevent the spread of HIV, the virus that causes AIDS.
Nanoparticles (purple) carrying melittin (green) fuse with HIV (small circles with spiked outer ring), destroying the virus’s protective envelope. Molecular bumpers (small red ovals) prevent the nanoparticles from harming the body’s normal cells, which are much larger in size.
“Our hope is that in places where HIV is running rampant, people could use this gel as a preventive measure to stop the initial infection,” says Joshua L. Hood, MD, PhD, a research instructor in medicine.
The study appears in the current issue of Antiviral Therapy.
Source: http://news.wustl.edu/

C. Shad Thaxton, of the Robert H. Lurie Comprehensive Cancer Center at Northwestern and member of the Northwestern University Center of Cancer Nanotechnology Excellence, and Leo Gordon, of Northwestern’s Feinberg School of Medicine, led research team that developed a biomimetic High-density lipoprotein – HDL – nanostructure. HDL is well-known for its role in protecting the body from developing coronary artery disease, but HDL also helps lymphomas and other cancers acquire the large amounts of cholesterol they need to maintain the structure of their cell membranes as they grow rapidly. Researchers at Northwestern University have taken advantage of this dependency on HDL to create an HDL-mimicking nanoparticle that starves lymphoma cells of cholesterol, triggering them to commit programmed cell death without the use of any other anticancer agent.To create their biomimetic HDL nanostructures, the researchers start with spherical gold nanoparticles that are five nanometers in diameter and add the human protein ApoA1 and two phospholipids found in native HDLs.

Drs. Thaxton and Gordon and their collaborators then treated mice with human lymphomas with the biomimetic HDL nanoparticles. This treatment stopped tumor growth when the tumors were derived from lymphoma cells.

Source: http://nano.cancer.gov/

New research from Rice University, Baylor College of Medicine (BCM) and the Puget Sound Blood Center (PSBC) has revealed how stresses of flow in the small blood vessels of the heart and brain could cause a common protein to change shape and form dangerous blood clots. The scientists were surprised to find that the proteins could remain in the dangerous, clot-initiating shape for up to five hours before returning to their normal, healthy shape.The study — the first of its kind — focused on a protein called von Willebrand factor, or VWF, a key player in clot formation. A team led by Rice physicist Ching-Hwa Kiang found that “shear” forces, like those found in small arteries of patients with atherosclerosis, cause snippets of nonclotting VWF to change into a clot-forming shape for hours at a time. The finding appears online in Physical Review Letters.

New research has revealed how stresses of flow in the bloodstream can cause a common protein to change shape and initiate the formation of dangerous blood clots. Rice University study co-authors include (from left) Eric Frey, Ching-Hwa Kiang, Joel Moake and Sithara Wijeratne.
“When I first heard what Dr. Kiang’s team had found, I was shocked,” said blood platelet expert Dr. Joel Moake, a study co-author who holds joint appointments at Rice and BCM. Moake, whose research group was the first to describe how high shear stress could cause platelets to stick to VWF, said, “I had thought that the condition might last for such a short time that it would be unmeasurable. No one expected to find that this condition would persist for hours. This has profound clinical implications.”

Source: http://news.rice.edu/

Using cutting-edge X-ray techniques, Cornell researchers have uncovered cellular-level detail of what happens when bone bears repetitive stress over time, visualizing damage at smaller scales than previously observed. Their work could offer clues into how bone fractures could be prevented. More: from athletes to individuals suffering from osteoporosis, bone fractures are usually the result of tiny cracks accumulating over time — invisible rivulets of damage that, when coalesced, lead to that painful break.
Marjolein van der Meulen, the Swanson Professor of Biomedical Engineering in the Sibley School of Mechanical and Aerospace Engineering, led the study published online March 5 in PLOS One using transmission X-ray microscopy at the Stanford Synchrotron Radiation Lightsource, part of the SLAC National Accelerator Laboratory.

Transmission X-ray microscope images of damage generated in a bone sample and stained with lead-uranyl acetate. White is the staining of microdamage, gray is bone and black is background. On the left is one-time loading of the sample, and on the right is repeated loading.

“In skeletal research, people have been trying to understand the role of damage,” said van der Meulen, whose research is called mechanobiology — how mechanics intersects with biological processes. “One of the things people have hypothesized is that damage is one of the stimuli that cells are sensing.”

Source: http://www.news.cornell.edu/