#Silicone vaginal rings deliver antiviral drugs, protect women against HIV Researchers at University Jean Monnet of Saint-Etienne,
France have succeeded in developing a vaginal silicone ring that delivers molecules that act on both HIV and herpes virus.
This research is presented at the 55th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC/ICC."
"We succeeded in creating a ring that can deliver hydrophilic molecules such as tenofovir, active on HIV-1,
despite the fact that silicone is a hydrophobic compound, "said Meriam Memmi, author of the study and Phd candidate at University Jean Monnet of Saint-Etienne, France.
This was possible due to the addition of a hydrophilic compound to the silicone, which allowed the drugs to be released from their reservoirs.
Vaginal rings with multiple reservoirs present a promising way for preventing sexually transmitted infections (STIS) and notably HIV infection in young women with high risk of exposure.
Some of the rings presented in this study were shown to release concentrations of drugs between 1. 5 and 3. 5 mg/day for acyclovir and 3 to 5 mg/day for tenofovir for as long as 50 days,
which corresponds to doses capable of preventing viral sexual-transmitted infections such as HIV-1 infection, Hepatitis b and genital herpes.
These preliminary results demonstrate the ability of silicone rings to continuously deliver hydrophilic antiviral drugs for a long period of time at a concentration that would be effective for neutralizing the viruses present in semen.
"The aim of our study was to develop a vaginal silicone ring that was nontoxic to the health of users
STIS of viral origin constitute a major public health concern, notably in women from low-income countries who were shown to be infected with HIV-1 early in their sexual live,
The work was performed at the University Jean Monnet of Saint-Etienne, France, in close collaboration between a team of virologists belonging to the GIMAP group under the supervision of Pr.
Bruno Pozzetto and of chemists from the Polymer Materials Engineering Laboratory under the supervision of Pr.
Christian Carrot, with the help of Mr. Blaise Figuereo, a silicone engineer who designed the apparatus used to create the reservoir rings s
and functional materials 3d printing is revolutionizing the production of lightweight structures, soft robots and flexible electronics,
including the electronics, a 3d printer must be able to seamlessly transition from a flexible material that moves with your joints for wearable applications,
to a rigid material that accommodates the electronic components. It would also need to be embed able to electrical circuitry using multiple inks of varying conductivity and resistivity,
and print concentrated viscoelastic inks that allow for the simultaneous control of composition and geometry during printing.
and could pave the way for entirely 3d printed wearable devices, soft robots, and electronics. The research was led by Jennifer A. Lewis, the Hansjörg Wyss Professor of Biologically Inspired Engineering at the Harvard John A. Paulson School of engineering and Applied sciences (SEAS) and a Core Faculty member at the Wyss Institute for Biologically Inspired Engineering
at Harvard. The work was published in the Proceedings of the National Academy of Sciences (PNAS.
Mixing complex fluids is fundamental for printing a broad range of materials. But most mixing approaches are passive,
This method works well with low-viscosity fluids, but is ineffective with high-viscosity fluids, like gels, especially in small volumes over short timescales.
along with Thomas Ober, postdoctoral research scholar at the Wyss Institute; and Daniele Foresti, the Society in Science Branco Weiss postdoctoral fellow.
They showed that silicone elastomers can be printed seamlessly into gradient architectures composed of soft and rigid regions.
These structures may find potential application in flexible electronics, wearable devices, and soft robotics. They also printed reactive materials,
"The recent work by the Lewis Group is a significant advancement to the field of additive manufacturing,
This work will be foundational for applications which required integrated electrical and structural materials.""Lewis'lab also recently designed another printhead that can rapidly switch between multiple inks within a single nozzle,
#Physicists determine 3-D positions of individual atoms for the first time Atoms are the building blocks of all matter On earth,
a UCLA professor of physics and astronomy and a member of UCLA's California Nanosystems Institute, is published Sept. 21 in the online edition of the journal Nature Materials.
For more than 100 years, researchers have inferred how atoms are arranged in three-dimensional space using a technique called X-ray crystallography,
which involves measuring how light waves scatter off of a crystal. However, X-ray crystallography only yields information about the average positions of many billions of atoms in the crystal
and not about individual atoms'precise coordinates.""It's like taking an average of people On earth,
"Because X-ray crystallography doesn't reveal the structure of a material on a per-atom basis,
when the materials are components of machines like jet engines.""Point defects are very important to modern science and technology,
However, scanning transmission electron microscopes only produce two-dimensional images. So creating a 3-D picture requires scientists to scan the sample once
and re-scan it--repeating the process until the desired spatial resolution is achieved--before combining the data from each scan using a computer algorithm.
Using a scanning transmission electron microscope at the Lawrence Berkeley National Laboratory's Molecular Foundry, Miao and his colleagues analyzed a small piece of tungsten,
"said Peter Ercius, a staff scientist at Lawrence Berkeley National Laboratory and an author of the paper.
thanks to the electron beam energy being kept below the radiation damage threshold of tungsten. Miao and his team showed that the atoms in the tip of the tungsten sample were arranged in nine layers, the sixth
"I think this work will create a paradigm shift in how materials are characterized in the 21st century,
and are discussed in many physics and materials science textbooks. Our results are the first experimental determination of a point defect inside a material in three dimensions
The record peak brilliance of the light source makes it an ultrasensitive detector for the infrared molecular finger print region,
or tissue which are telltale signs of DNA mutation or the presence of cellular malfunctions such as cancer.
Consequently, shining light through a sample leaves the resonant fingerprints in the spectrum allowing identification. The absence of light sources that cover enough of the infrared spectrum with sufficient brilliance to detect minute concentrations originating from onco-metaboloids has been the main challenge in cancer detection.
Now, ICFO researchers have collaborated with colleagues from MPQ/LMU to develop a light source which addresses this need.
which is so short that the electric field oscillates only twice. These characteristics, in combination with its coherence, make the light source a compact and ultrasensitive molecular detector.
Prof. Jens Biegert and his colleagues at ICFO are currently investigating molecular sensitivity for the identification of cancer biomarkers on the single cell level using all optical techniques in the mid-wave infrared wavelength range g
#Fatigue-free, stretchable conductor created Researchers have discovered a new stretchable, transparent conductor that can be folded
This is a crucial step in creating a new generation of foldable electronics--think a flat-screen television that can be rolled up for easy portability--and implantable medical devices.
The work, published Monday in the Proceedings of the National Academy of Sciences, pairs gold nanomesh with a stretchable substrate made with polydimethylsiloxane, or PDMS.
The substrate is stretched before the gold nanomesh is placed on it--a process known as"prestretching "--and the material showed no sign of fatigue
The gold nanomesh also proved conducive to cell growth, indicating it is a good material for implantable medical devices.
Fatigue is a common problem for researchers trying to develop a flexible, transparent conductor, making many materials that have good electrical conductivity,
flexibility and transparency--all three are needed for foldable electronics--wear out too quickly to be said practical
Zhifeng Ren, a physicist at the University of Houston and principal investigator at the Texas Center for Superconductivity,
who was the lead author for the paper. The new material, produced by grain boundary lithography
In materials science,"fatigue"is used to describe the structural damage to a material caused by repeated movement or pressure, known as"strain cycling."
That means the materials aren't durable enough for consumer electronics or biomedical devices.""Metallic materials often exhibit high cycle fatigue,
and fatigue has been a deadly disease for metals, "the researchers wrote.""We weaken the constraint of the substrate by making the interface between the Au (gold) nanomesh and PDMS slippery,
and expect the Au nanomesh to achieve superstretchability and high fatigue resistance, "they wrote in the paper."
"Free of fatigue here means that both the structure and the resistance do not change or have little change after many strain cycles."
"the Au nanomesh does not exhibit strain fatigue when it is stretched to 50 percent for 10,000 cycles."
The researchers used mouse embryonic fibroblast cells to determine biocompatibility; that, along with the fact that the stretchability of gold nanomesh on a slippery substrate resembles the bioenvironment of tissue
or organ surfaces, suggest the nanomesh"might be implanted in the body as a pacemaker electrode,
a connection to nerve endings or the central nervous system, a beating heart, and so on, "they wrote. Ren's lab reported the mechanics of making a new transparent and stretchable electric material,
using gold nanomesh, in a paper published in Nature Communications in January 2014. This work expands on that,
producing the material in a different way to allow it to remain fatigue-free through thousands of cycles s
#Engineers invent transparent coating that cools solar cells to boost efficiency Every time you stroll outside you emit energy into the universe:
Now three Stanford engineers have developed a technology that improves on solar panel performance by exploiting this basic phenomenon.
Their invention shunts away the heat generated by a solar cell under sunlight and cools it in a way that allows it to convert more photons into electricity.
The work by Shanhui Fan, a professor of electrical engineering at Stanford, research associate Aaswath P. Raman and doctoral candidate Linxiao Zhu is described in the current issue of Proceedings of the National Academy
of Sciences. The group's discovery tested on a Stanford rooftop, addresses a problem that has bedeviled long the solar industry:
The hotter solar cells get, the less efficient they become at converting the photons in light into useful electricity.
The Stanford solution is based on a thin, patterned silica material laid on top of a traditional solar cell.
The material is transparent to the visible sunlight that powers solar cells, but captures and emits thermal radiation,
or heat, from infrared rays.""Solar arrays must face the sun to function, even though that heat is detrimental to efficiency,
"Fan said.""Our thermal overlay allows sunlight to pass through, preserving or even enhancing sunlight absorption,
but it also cools the cell by radiating the heat out and improving the cell efficiency."
They presented that work in Nature, describing it as"radiative cooling "because it shunted thermal energy directly into the deep, cold void of space.
In their new paper, the researchers applied that work to improve solar array performance when the sun is beating down.
The Stanford team tested their technology on a custom-made solar absorber--a device that mimics the properties of a solar cell without producing electricity--covered with a micron-scale pattern designed to maximize the capability to dump heat
Their experiments showed that the overlay allowed visible light to pass through to the solar cells, but that it also cooled the underlying absorber by as much as 55 degrees Fahrenheit.
For a typical crystalline silicon solar cell with an efficiency of 20 percent, 55 F of cooling would improve absolute cell efficiency by over 1 percent,
a figure that represents a significant gain in energy production. The researchers said the new transparent thermal overlays work best in dry, clear environments,
which are preferred also sites for large solar arrays. They believe they can scale things up so commercial and industrial applications are feasible
perhaps using nanoprint lithography, which is a common technique for producing nanometer scale patterns.""That's not necessarily the only way,"said Raman, a co-first-author of the paper."
"New techniques and machines for manufacturing these kinds of patterns will continue to advance. I'm optimistic."
"Cooler cars Zhu said the technology has significant potential for any outdoor device or system that demands cooling
"Say you have a car that is bright red, "Zhu said.""You really like that color,
but you'd also like to take advantage of anything that could aid in cooling your vehicle during hot days.
#Virus re-engineered to deliver therapies to cells Stanford researchers have ripped the guts out of a virus
and totally redesigned its core to repurpose its infectious capabilities into a safe vehicle for delivering vaccines
and therapies directly where they are needed. The study reported today in the Proceedings of the National Academy of Sciences breathes new life into the field of targeted delivery,
the ongoing effort to fashion treatments that affect diseased areas but leave healthy tissue alone."
the professor of chemical engineering and of bioengineering at Stanford who led the study.""We make it smart by adding molecular tags that act like addresses to send the therapeutic payload where we want it to go."
"Using the smart particle for immunotherapy would involve tagging its outer surface with molecules designed to teach the body's disease-fighting cells to recognize
and destroy cancers, Swartz said. For Swartz and his principal collaborator, Yuan Lu, now a pharmacology researcher at the University of Tokyo, the result is a vindication.
When they first started the research four years ago, funding agencies said it couldn't be done.
It will require much more effort to accomplish the second goal--packing tiny quantities of medicines into the smart particles,
delivering the particles to and into diseased cells, and engineering them to release their payloads.'
'Proof of principle'"This was a proof-of-principle experiment so there's a lot of work to be done,
"Swartz said.""But I believe we can use this smart particle to deliver cancer-fighting immunotherapies that will have minimal side effects."
"Massachusetts institute of technology Professor Robert Langer, a leader in targeted drug delivery research who was connected not to the Stanford experiments,
also read the paper before publication.""This is terrific work, a beautiful paper, "Langer said.""Dr. Swartz and colleagues have done a remarkable job of stabilizing viruslike particles
and re-engineering their surface.""Targeted drug delivery is one of the ultimate goals of medicine
because it seeks to focus remedies on diseased cells, minimizing the side effects that occur when, for instance,
while treating cancer. Looking for a model in nature, many researchers focused on viruses, which target specific cells,
The new paper describes how the Stanford team designed a viruslike particle that is only a delivery vehicle with no infectious payload.
to carry a significant medical payload. But in practice this had proven so difficult that when Swartz floated the idea to funding agencies they said no.
Next steps Biotechnologists know how to build the complex protein structures they find in nature, but the Stanford team took this further.
they would hang vaccine tags on the spikes. If on the other hand, they wanted the capsid to deliver medicines to a sick cell,
they would hang address tags on the spikes. Finally, the researchers had to make all these modifications without destroying the miraculous capability of the capsid's DNA code to direct 240 copies of one protein to self-assemble into a hollow sphere with a spiky surface.
Swartz said the next step is to attach cancer tags to the outside of this smart particle,
to use it to train the immune system to recognize certain cancers. Those experiments would likely occur in mice.
After that he will add the next function--further engineering the DNA code to make sure that the protein can self-assemble around a small medicinal payload."
and different aspects are licensed to a biotechnology company in which Swartz has a founding interest. The approach is in its early stages
#Identifying the'dimmer switch'of diabetes Patrick Macdonald has dedicated much of his life to diabetes research.
but with his latest publication, he knows his work is playing a part. Macdonald, a Canada Research Chair in Islet Biology, associate professor in the University of Alberta's Faculty of medicine & Dentistry and member of the Alberta Diabetes Institute, is the senior author of a landmark study in the Journal of Clinical Investigation.
The researchers examined pancreatic islet cells from 99 human organ donors and identified a new molecular pathway that manages the amount of insulin produced by the pancreatic cells--essentially a'dimmer'switch that adjusts how much
According to Macdonald, the dimmer appears to be lost in Type 2 diabetes but can be restored and'turned back on'--reviving proper control of insulin secretion from islet cells of people with Type 2 diabetes.
The discovery is a potential game-changer in Type 2 diabetes research, leading to a new way of thinking about the disease and its future treatment."
"Understanding the islet cells in the pancreas that make insulin, how they work --and how they can fail--could lead to new ways to treat the disease,
delaying or even preventing diabetes, "says Macdonald. Ten million Canadians are living with diabetes or prediabetes.
The Canadian Diabetes Association reports that more than 20 Canadians are diagnosed newly with the disease every hour of every day.
It is also the seventh leading cause of death in Canada, with associated health-care costs estimated at nearly $9 billion a year.
Type 2 diabetes accounts for 90 per cent of all cases increasing the risk of blindness, nerve damage, stroke, heart disease and several other serious health conditions.
Macdonald believes the key to his latest research has been access to the Alberta Diabetes Institute's Isletcore.
The biobank, established with funding from the Alberta Diabetes Foundation and the U of A, collects pancreatic islets from organ donors--with and without diabetes--for diabetes research in Edmonton and across North america."
"Without access to this critical tissue through the Alberta Diabetes Institute Isletcore and the generosity of organ donors and their families, we would not have been able to carry out this study,
"says Macdonald.""If we want to learn about diabetes, and how to treat and prevent it,
studying the insulin-producing cells from donors with diabetes is a powerful way to do it."
"Though important new strides in the fight against Type 2 diabetes have been taken, Macdonald stresses that much more needs to be done.
The ability to restore and fix the dimmer switch in islet cells may have been proven on a molecular level,
but finding a way to translate those findings into clinical use could yet take decades.
Despite this, Macdonald believes the findings show an important new way forward.""We don't know enough to stop Type 2 diabetes yet,
but this is a large step towards understanding what's going wrong in the first place
#Building a biofuel-boosting Swiss Army knife Researchers at Michigan State university have built a molecular Swiss Army knife that streamlines the molecular machinery of cyanobacteria,
also known as blue-green algae, making biofuels and other green chemical production from these organisms more viable. The team has done in a year
In the current issue of Plant Cell, they describe how they fabricated a synthetic protein that not only improves the assembly of the carbon-fixing factory of cyanobacteria,
"The multifunctional protein we've built can be compared to a Swiss Army knife, "said Raul Gonzalez-Esquer, MSU doctoral researcher and the paper's lead author."
"For this research, Gonzalez-Esquer worked with Cheryl Kerfeld, the Hannah Distinguished Professor of Structural Bioengineering in the Michigan State university-DOE Plant Research Lab,
and Tyler Shubitowski, MSU undergraduate student. Kerfield's lab studies bacterial microcompartments, or BMCS. These are self-assembling cellular organs that perform myriad metabolic functions,
and in a sense, they are molecular factories with many different pieces of machinery. They modernized the factory by updating the carboxysome,
a particularly complex BMC that requires a series of protein-protein interactions involving at least six gene products to form a metabolic core that takes CO2 out of the atmosphere and converts it into sugar.
To streamline this process the team created a hybrid protein in cyanobacteria, organisms that have many potential uses for making green chemicals or biofuels.
a grinder to process them and a brewing machine, we've built a single coffeemaker where it all happens in one place,
and produces the finished product with a smaller investment.""This proof of concept also shows that BMCS can be broken down to the sum of their parts,
BMCS have enormous potential for bioengineering, said Kerfeld, who also is an affiliate of the Berkeley National Laboratory's Physical Biosciences Division."
"We've showed that we can greatly simplify the construction of these factories, "she said."
"We can now potentially redesign other naturally occurring factories or dream up new ones for metabolic processes we'd like to install in bacteria."
"However, this altered cyanobacterial species won't be taking over any ponds, or the world, anytime soon. While the improved organisms excel at photosynthesis in a lab setting,
much less dominate, in the natural environment
#Proteins assemble, disassemble on command Scientists have deciphered the genetic code that instructs proteins to either self-assemble
or disassemble in response to environmental stimuli, such as changes in temperature, salinity or acidity. The discovery provides a new platform for drug delivery systems and an entirely different view of cellular functions.
and is the first time that scientists have reported the ability to create biological structures that are programmed readily to assemble
With this knowledge in hand, researchers have opened a new world for designer proteins and investigations into nanotechnology
biotechnology and medical treatments.""The very simple design rules that we have discovered provide a powerful engineering tool for many biomedical
and biotechnology applications,"said Ashutosh Chilkoti, chair of the Department of Biomedical engineering at Duke.""We can now,
with a flick of a switch and a temperature jump, make a huge range of biological molecules that either assemble or disassemble."
"The study investigated several triggers that can cause protein structures to assemble or break apart, but it primarily focused on heat.
Protein-based structures that self-assemble when heated and remain stable inside of the bloodstream have long been used in a variety of applications.
The opposite behavior, however, has eluded long researchers, especially outside of the carefully controlled environment of a chemistry lab."
"Nobody has been able to make these kinds of materials with the degree of complexity that we have demonstrated now,
"said Felipe Garcia Quiroz, a former graduate student in Chilkoti's laboratory and first author of the new study.
however, drugs could be encapsulated in protein cages that accumulate inside of a tumor and dissolve once heated.
they could break down into additional therapeutic agents. We can now design two things into one."
Because the laboratory identified the genetic sequences that encode this behavior, they were able to point out a long list of human proteins that likely exhibit it."
"These findings will be exciting to both the materials science and the biochemistry communities,"said Quiroz.""They'll be able to push the limits of what we know about these kinds of materials
and then go back to explore how biology is already making use of them
#Two-drug combination shows promise against one type of pancreatic cancer One form of pancreatic cancer has a new enemy:
a two-drug combination discovered by UF Health researchers that inhibits tumors and kills cancer cells in mouse models.
For the first time, researchers have shown that a certain protein becomes overabundant in pancreatic neuroendocrine tumors, allowing them to thrive.
They also found that pairing a synthetic compound with an existing drug provides a more effective anticancer punch than a single drug.
The findings were published recently in the Journal of the National Cancer Institute by a group that includes Rony A. François, an M d./Ph d. student working with Maria Zajac-Kaye, Ph d.
an associate professor in the UF College of Medicine's department of anatomy and cell biology. Finding new treatments is critical
because less than 5 percent of patients with pancreatic neuroendocrine tumors respond to everolimus, the most commonly used pharmaceutical,
Neuroendocrine tumors, which form in the hormone-making islet cells, account for 3 percent to 5 percent of pancreatic malignancies
and have a five-year survival rate of about 42 percent, according to the National Cancer Institute.
Pancreatic neuroendocrine tumors are increasingly common, which medical experts and researches have attributed to better diagnostic imaging,
an aging population and heightened awareness of the disease stemming from the 2011 death of Apple Inc. cofounder Steve jobs. Zajac-Kaye's group discovered that a single protein is behind the process that allows pancreatic neuroendocrine tumors to thrive.
The protein, known as focal adhesion kinase, or FAK, activates an enzyme called AKT, which helps islet cells in the pancreas to survive.
But when islet cells begin turning into tumors, the FAK protein gets overproduced, researchers found.
This overabundance of the protein allows tumors to resist chemotherapy and evade efforts to kill them off.
After identifying FAK's role in tumor development François started looking for ways to get it in check.
One idea was finding something to make the antitumor drug everolimus more effective.""Once we figured out that FAK was started important,
Researchers then tested its effectiveness on human pancreatic cells that had been implanted in mouse models. Daily doses of the compound reduced tumor volume by about 50 percent after 25 days, they found.
Next researchers paired the compound with everolimus. While everolimus can extend some patients'lives by holding tumors in check,
it does little to make them regress and is not effective for many people. François wondered if the synthetic compound would make everolimus more effective.
In testing on two mouse cell lines, the drug combination reduced the viability of cancer cells by about 50 percent
The findings also have potential uses for most other types of solid tumors, including those affecting the lungs and ovaries,
Next, researchers would like to study how the two-drug approach works in humans, although no clinical trials have yet been designed or scheduled h
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