Tag Archives: Texas A&M University

Injectable bandages for internal bleeding and hydrogel for the brain

This injectable bandage could be a gamechanger (as they say) if it can be taken beyond the ‘in vitro’ (i.e., petri dish) testing stage. A May 22, 2018 news item on Nanowerk makes the announcement (Note: A link has been removed),

While several products are available to quickly seal surface wounds, rapidly stopping fatal internal bleeding has proven more difficult. Now researchers from the Department of Biomedical Engineering at Texas A&M University are developing an injectable hydrogel bandage that could save lives in emergencies such as penetrating shrapnel wounds on the battlefield (Acta Biomaterialia, “Nanoengineered injectable hydrogels for wound healing application”).

A May 22, 2018 US National Institute of Biomedical Engineering and Bioengiineering news release, which originated the news item, provides more detail (Note: Links have been removed),

The researchers combined a hydrogel base (a water-swollen polymer) and nanoparticles that interact with the body’s natural blood-clotting mechanism. “The hydrogel expands to rapidly fill puncture wounds and stop blood loss,” explained Akhilesh Gaharwar, Ph.D., assistant professor and senior investigator on the work. “The surface of the nanoparticles attracts blood platelets that become activated and start the natural clotting cascade of the body.”

Enhanced clotting when the nanoparticles were added to the hydrogel was confirmed by standard laboratory blood clotting tests. Clotting time was reduced from eight minutes to six minutes when the hydrogel was introduced into the mixture. When nanoparticles were added, clotting time was significantly reduced, to less than three minutes.

In addition to the rapid clotting mechanism of the hydrogel composite, the engineers took advantage of special properties of the nanoparticle component. They found they could use the electric charge of the nanoparticles to add growth factors that efficiently adhered to the particles. “Stopping fatal bleeding rapidly was the goal of our work,” said Gaharwar. “However, we found that we could attach growth factors to the nanoparticles. This was an added bonus because the growth factors act to begin the body’s natural wound healing process—the next step needed after bleeding has stopped.”

The researchers were able to attach vascular endothelial growth factor (VEGF) to the nanoparticles. They tested the hydrogel/nanoparticle/VEGF combination in a cell culture test that mimics the wound healing process. The test uses a petri dish with a layer of endothelial cells on the surface that create a solid skin-like sheet. The sheet is then scratched down the center creating a rip or hole in the sheet that resembles a wound.

When the hydrogel containing VEGF bound to the nanoparticles was added to the damaged endothelial cell wound, the cells were induced to grow back and fill-in the scratched region—essentially mimicking the healing of a wound.

“Our laboratory experiments have verified the effectiveness of the hydrogel for initiating both blood clotting and wound healing,” said Gaharwar. “We are anxious to begin tests in animals with the hope of testing and eventual use in humans where we believe our formulation has great potential to have a significant impact on saving lives in critical situations.”

The work was funded by grant EB023454 from the National Institute of Biomedical Imaging and Bioengineering (NIBIB), and the National Science Foundation. The results were reported in the February issue of the journal Acta Biomaterialia.

The paper was published back in April 2018 and there was an April 2, 2018 Texas A&M University news release on EurekAlert making the announcement (and providing a few unique details),

A penetrating injury from shrapnel is a serious obstacle in overcoming battlefield wounds that can ultimately lead to death.Given the high mortality rates due to hemorrhaging, there is an unmet need to quickly self-administer materials that prevent fatality due to excessive blood loss.

With a gelling agent commonly used in preparing pastries, researchers from the Inspired Nanomaterials and Tissue Engineering Laboratory have successfully fabricated an injectable bandage to stop bleeding and promote wound healing.

In a recent article “Nanoengineered Injectable Hydrogels for Wound Healing Application” published in Acta Biomaterialia, Dr. Akhilesh K. Gaharwar, assistant professor in the Department of Biomedical Engineering at Texas A&M University, uses kappa-carrageenan and nanosilicates to form injectable hydrogels to promote hemostasis (the process to stop bleeding) and facilitate wound healing via a controlled release of therapeutics.

“Injectable hydrogels are promising materials for achieving hemostasis in case of internal injuries and bleeding, as these biomaterials can be introduced into a wound site using minimally invasive approaches,” said Gaharwar. “An ideal injectable bandage should solidify after injection in the wound area and promote a natural clotting cascade. In addition, the injectable bandage should initiate wound healing response after achieving hemostasis.”

The study uses a commonly used thickening agent known as kappa-carrageenan, obtained from seaweed, to design injectable hydrogels. Hydrogels are a 3-D water swollen polymer network, similar to Jell-O, simulating the structure of human tissues.

When kappa-carrageenan is mixed with clay-based nanoparticles, injectable gelatin is obtained. The charged characteristics of clay-based nanoparticles provide hemostatic ability to the hydrogels. Specifically, plasma protein and platelets form blood adsorption on the gel surface and trigger a blood clotting cascade.

“Interestingly, we also found that these injectable bandages can show a prolonged release of therapeutics that can be used to heal the wound” said Giriraj Lokhande, a graduate student in Gaharwar’s lab and first author of the paper. “The negative surface charge of nanoparticles enabled electrostatic interactions with therapeutics thus resulting in the slow release of therapeutics.”

Nanoparticles that promote blood clotting and wound healing (red discs), attached to the wound-filling hydrogel component (black) form a nanocomposite hydrogel. The gel is designed to be self-administered to stop bleeding and begin wound-healing in emergency situations. Credit: Lokhande, et al. 1

Here’s a link to and a citation for the paper,

Nanoengineered injectable hydrogels for wound healing application by Giriraj Lokhande, James K. Carrow, Teena Thakur, Janet R. Xavier, Madasamy Parani, Kayla J. Bayless, Akhilesh K. Gaharwar. Acta Biomaterialia Volume 70, 1 April 2018, Pages 35-47
https://doi.org/10.1016/j.actbio.2018.01.045

This paper is behind a paywall.

Hydrogel and the brain

It’s been an interesting week for hydrogels. On May 21, 2018 there was a news item on ScienceDaily about a bioengineered hydrogel which stimulated brain tissue growth after a stroke (mouse model),

In a first-of-its-kind finding, a new stroke-healing gel helped regrow neurons and blood vessels in mice with stroke-damaged brains, UCLA researchers report in the May 21 issue of Nature Materials.

“We tested this in laboratory mice to determine if it would repair the brain in a model of stroke, and lead to recovery,” said Dr. S. Thomas Carmichael, Professor and Chair of neurology at UCLA. “This study indicated that new brain tissue can be regenerated in what was previously just an inactive brain scar after stroke.”

The brain has a limited capacity for recovery after stroke and other diseases. Unlike some other organs in the body, such as the liver or skin, the brain does not regenerate new connections, blood vessels or new tissue structures. Tissue that dies in the brain from stroke is absorbed, leaving a cavity, devoid of blood vessels, neurons or axons, the thin nerve fibers that project from neurons.

After 16 weeks, stroke cavities in mice contained regenerated brain tissue, including new neural networks — a result that had not been seen before. The mice with new neurons showed improved motor behavior, though the exact mechanism wasn’t clear.

Remarkable stuff.

Of musical parodies, Despacito, and evolution

What great timing, I just found out about a musical science parody featuring evolution and biology and learned of the latest news about the study of evolution on one of the islands in the Galapagos (where Charles Darwin made some of his observations). Thanks to Stacey Johnson for her November 24, 2017 posting on the Signals blog for featuring Evo-Devo (Despacito Biology Parody), an A Capella Science music video from Tim Blais,

Now, for the latest regarding the Galapagos and evolution (from a November 24, 2017 news item on ScienceDaily),

The arrival 36 years ago of a strange bird to a remote island in the Galapagos archipelago has provided direct genetic evidence of a novel way in which new species arise.

In this week’s issue of the journal Science, researchers from Princeton University and Uppsala University in Sweden report that the newcomer belonging to one species mated with a member of another species resident on the island, giving rise to a new species that today consists of roughly 30 individuals.

The study comes from work conducted on Darwin’s finches, which live on the Galapagos Islands in the Pacific Ocean. The remote location has enabled researchers to study the evolution of biodiversity due to natural selection.

The direct observation of the origin of this new species occurred during field work carried out over the last four decades by B. Rosemary and Peter Grant, two scientists from Princeton, on the small island of Daphne Major.

A November 23, 2017 Princeton University news release on EurekAlert, which originated the news item, provides more detail,

“The novelty of this study is that we can follow the emergence of new species in the wild,” said B. Rosemary Grant, a senior research biologist, emeritus, and a senior biologist in the Department of Ecology and Evolutionary Biology. “Through our work on Daphne Major, we were able to observe the pairing up of two birds from different species and then follow what happened to see how speciation occurred.”

In 1981, a graduate student working with the Grants on Daphne Major noticed the newcomer, a male that sang an unusual song and was much larger in body and beak size than the three resident species of birds on the island.

“We didn’t see him fly in from over the sea, but we noticed him shortly after he arrived. He was so different from the other birds that we knew he did not hatch from an egg on Daphne Major,” said Peter Grant, the Class of 1877 Professor of Zoology, Emeritus, and a professor of ecology and evolutionary biology, emeritus.

The researchers took a blood sample and released the bird, which later bred with a resident medium ground finch of the species Geospiz fortis, initiating a new lineage. The Grants and their research team followed the new “Big Bird lineage” for six generations, taking blood samples for use in genetic analysis.

In the current study, researchers from Uppsala University analyzed DNA collected from the parent birds and their offspring over the years. The investigators discovered that the original male parent was a large cactus finch of the species Geospiza conirostris from Española island, which is more than 100 kilometers (about 62 miles) to the southeast in the archipelago.

The remarkable distance meant that the male finch was not able to return home to mate with a member of his own species and so chose a mate from among the three species already on Daphne Major. This reproductive isolation is considered a critical step in the development of a new species when two separate species interbreed.

The offspring were also reproductively isolated because their song, which is used to attract mates, was unusual and failed to attract females from the resident species. The offspring also differed from the resident species in beak size and shape, which is a major cue for mate choice. As a result, the offspring mated with members of their own lineage, strengthening the development of the new species.

Researchers previously assumed that the formation of a new species takes a very long time, but in the Big Bird lineage it happened in just two generations, according to observations made by the Grants in the field in combination with the genetic studies.

All 18 species of Darwin’s finches derived from a single ancestral species that colonized the Galápagos about one to two million years ago. The finches have since diversified into different species, and changes in beak shape and size have allowed different species to utilize different food sources on the Galápagos. A critical requirement for speciation to occur through hybridization of two distinct species is that the new lineage must be ecologically competitive — that is, good at competing for food and other resources with the other species — and this has been the case for the Big Bird lineage.

“It is very striking that when we compare the size and shape of the Big Bird beaks with the beak morphologies of the other three species inhabiting Daphne Major, the Big Birds occupy their own niche in the beak morphology space,” said Sangeet Lamichhaney, a postdoctoral fellow at Harvard University and the first author on the study. “Thus, the combination of gene variants contributed from the two interbreeding species in combination with natural selection led to the evolution of a beak morphology that was competitive and unique.”

The definition of a species has traditionally included the inability to produce fully fertile progeny from interbreeding species, as is the case for the horse and the donkey, for example. However, in recent years it has become clear that some closely related species, which normally avoid breeding with each other, do indeed produce offspring that can pass genes to subsequent generations. The authors of the study have previously reported that there has been a considerable amount of gene flow among species of Darwin’s finches over the last several thousands of years.

One of the most striking aspects of this study is that hybridization between two distinct species led to the development of a new lineage that after only two generations behaved as any other species of Darwin’s finches, explained Leif Andersson, a professor at Uppsala University who is also affiliated with the Swedish University of Agricultural Sciences and Texas A&M University. “A naturalist who came to Daphne Major without knowing that this lineage arose very recently would have recognized this lineage as one of the four species on the island. This clearly demonstrates the value of long-running field studies,” he said.

It is likely that new lineages like the Big Birds have originated many times during the evolution of Darwin’s finches, according to the authors. The majority of these lineages have gone extinct but some may have led to the evolution of contemporary species. “We have no indication about the long-term survival of the Big Bird lineage, but it has the potential to become a success, and it provides a beautiful example of one way in which speciation occurs,” said Andersson. “Charles Darwin would have been excited to read this paper.”

Here’s a link to and a citation for the paper,

Rapid hybrid speciation in Darwin’s finches by Sangeet Lamichhaney, Fan Han, Matthew T. Webster, Leif Andersson, B. Rosemary Grant, Peter R. Grant. Science 23 Nov 2017: eaao4593 DOI: 10.1126/science.aao4593

This paper is behind a paywall.

Happy weekend! And for those who love their Despacito, there’s this parody featuring three Italians in a small car (thanks again to Stacey Johnson’s blog posting),

Teslaphoresis; self-assembling materials from a distance

Getting carbon nanotubes to self-assemble from a distance is possible according to an April 14, 2016 news item on ScienceDaily,

Scientists at Rice University have discovered that the strong force field emitted by a Tesla coil causes carbon nanotubes to self-assemble into long wires, a phenomenon they call “Teslaphoresis.”

An April 14, 2016 Rice University (US) news release, (also on EurekAlert) which originated the news item, expands on the theme,

Cherukuri [Rice chemist Paul Cherukuri] sees this research as setting a clear path toward scalable assembly of nanotubes from the bottom up.

The system works by remotely oscillating positive and negative charges in each nanotube, causing them to chain together into long wires. Cherukuri’s specially designed Tesla coil even generates a tractor beam-like effect as nanotube wires are pulled toward the coil over long distances.

This force-field effect on matter had never been observed on such a large scale, Cherukuri said, and the phenomenon was unknown to Nikola Tesla, who invented the coil in 1891 with the intention of delivering wireless electrical energy.

“Electric fields have been used to move small objects, but only over ultrashort distances,” Cherukuri said. “With Teslaphoresis, we have the ability to massively scale up force fields to move matter remotely.”

The researchers discovered that the phenomenon simultaneously assembles and powers circuits that harvest energy from the field. In one experiment, nanotubes assembled themselves into wires, formed a circuit connecting two LEDs and then absorbed energy from the Tesla coil’s field to light them.

Cherukuri realized a redesigned Tesla coil could create a powerful force field at distances far greater than anyone imagined. His team observed alignment and movement of the nanotubes several feet away from the coil. “It is such a stunning thing to watch these nanotubes come alive and stitch themselves into wires on the other side of the room,” he said.

Nanotubes were a natural first test material, given their heritage at Rice, where the HiPco production process was invented. But the researchers envision many other nanomaterials can be assembled as well.

Lindsey Bornhoeft, the paper’s lead author and a biomedical engineering graduate student at Texas A&M University, said the directed force field from the bench-top coil at Rice is restricted to just a few feet. To examine the effects on matter at greater distances would require larger systems that are under development. Cherukuri suggested patterned surfaces and multiple Tesla coil systems could create more complex self-assembling circuits from nanoscale-sized particles.

Cherukuri and his wife, Tonya, also a Rice alum and a co-author of the paper, noted that their son Adam made some remarkable observations while watching videos of the experiment. “I was surprised that he noticed patterns in nanotube movements that I didn’t see,” Cherukuri said. “I couldn’t make him an author on the paper, but both he and his little brother John are acknowledged for helpful discussions.”

Cherukuri knows the value of youthful observation — and imagination — since he started designing Tesla coils as a teen. “I would have never thought, as a 14-year-old kid building coils, that it was going to be useful someday,” he said.

Cherukuri and his team self-funded the work, which he said made it more meaningful for the group. “This was one of the most exciting projects I’ve ever done, made even more so because it was an all-volunteer group of passionate scientists and students. But because Rice has this wonderful culture of unconventional wisdom, we were able to make an amazing discovery that pushes the frontiers of nanoscience.”

The teammates look forward to seeing where their research leads. “These nanotube wires grow and act like nerves, and controlled assembly of nanomaterials from the bottom up may be used as a template for applications in regenerative medicine,” Bornhoeft said.

“There are so many applications where one could utilize strong force fields to control the behavior of matter in both biological and artificial systems,” Cherukuri said. “And even more exciting is how much fundamental physics and chemistry we are discovering as we move along. This really is just the first act in an amazing story.”

Rice University has produced a video featuring the research and the researchers,

Here’s a link to and a citation for the paper,

Teslaphoresis of Carbon Nanotubes by Lindsey R. Bornhoeft, Aida C. Castillo, Preston R. Smalley, Carter Kittrell, Dustin K. James, Bruce E. Brinson, Thomas R. Rybolt, Bruce R. Johnson, Tonya K. Cherukuri†, and Paul Cherukuri. ACS Nano, Article ASAP DOI: 10.1021/acsnano.6b02313 Publication Date (Web): April 13, 2016

Copyright © 2016 American Chemical Society

This paper is behind a paywall.

The Tesla coil was created by Nikola Tesla, a renowned Serbian-American scientist and engineer.

Nanotwinned copper materials with nanovoids are damage-tolerant with regard to radiation

The research comes out of the Texas A&M University, from a May 29, 2015 news item on Azonano,

Material performance in extreme radiation environments is central to the design of future nuclear reactors. Radiation in metallic materials typically induces significant damage in the form of dislocation loops and continuous void growth, manifested as void swelling. In certain metallic materials with low-to-intermediate stacking fault energy, such as Cu [copper] and austenitic stainless steels, void swelling can be significant and lead to substantial degradation of mechanical properties.

By using in situ heavy ion irradiation in a transmission electron microscope (in collaboration with M.A. Kirk at IVEM facility at Argonne National Lab), Zhang’s [Xinghang Zhang] student, Dr. Youxing Chen, reported a surprising phenomena: during radiation of nanotwinned Cu, preexisting nanovoids disappeared.

A May 28, 2015 Texas A & M University news release, which originated the news item, expands on the theme,

The self-healing capability of Cu arises from the existence of three-dimensional coherent and incoherent twin boundary networks. Such a network enables capture and rapid transportation of radiation induced point defects and their clusters to nanovoids (as evidenced by in situ radiation experiments and molecular dynamics simulations performed in collaboration with Jian Wang at Los Alamos National Laboratory), and thus lead to the mutual elimination of defect clusters and nanovoids.

This study also introduces the concept that deliberate introduction of nanovoids in conjunction with nanotwins may enable unprecedented radiation tolerance in metallic materials. [emphasis mine] The mobile twin boundaries are swift carriers that load and transfer “customers” (defect clusters), and nanovoids are also necessary to accommodate these “customers.” The in situ radiation study also shows that after annihilation of nanovoids, the self-healing capability of nanotwinned Cu is degraded, highlighting the significance of nanovoids. The concept developed from this study, the combination of nanovoids with nanotwin networks, may also stimulate the design of damage tolerant materials in general that are subjected other extreme environments, such as high stress and high pressure impact.

Here’s a link to and a citation for the paper,

Damage-tolerant nanotwinned metals with nanovoids under radiation environments by Y. Chen, K Y. Yu, Y. Liu, S. Shao, H. Wang, M. A. Kirk, J. Wang, & X. Zhang. Nature Communications 6, Article number: 7036 doi:10.1038/ncomms8036 Published 24 April 2015

This paper is open access.

Oh so cute! Baby nanotubes!

Scientists from the US National Institute of Standards and Technology and from two US universities have successfully filmed the formation of single-walled carbon nanotubes (SWCNTs) according to a Dec. 2, 2014 news item on Nanowerk,

Single-walled carbon nanotubes are loaded with desirable properties. In particular, the ability to conduct electricity at high rates of speed makes them attractive for use as nanoscale transistors. But this and other properties are largely dependent on their structure, and their structure is determined when the nanotube is just beginning to form.

In a step toward understanding the factors that influence how nanotubes form, researchers at the National Institute of Standards and Technology (NIST), the University of Maryland, and Texas A&M have succeeded in filming them when they are only a few atoms old. These nanotube “baby pictures” give crucial insight into how they germinate and grow, potentially opening the way for scientists to create them en masse with just the properties that they want.

A Dec. 1, 2014 NIST news release, which originated the news item, explains how scientists managed to make movies of SWCNTs as they formed,

To better understand how carbon nanotubes grow and how to grow the ones you want, you need to understand the very beginning of the growth process, called nucleation. To do that, you need to be able to image the nucleation process as it happens. However, this is not easy because it involves a small number of fast-moving atoms, meaning you have to take very high resolution pictures very quickly.

Because fast, high-resolution cameras are expensive, NIST scientists instead slowed the growth rate by lowering the pressure inside their instrument, an environmental scanning transmission electron microscope. Inside the microscope’s chamber, under high heat and low pressure, the team watched as carbon atoms generated from acetylene rained down onto 1.2-nanometer bits of cobalt carbide, where they attached, formed into graphene, encircled the nanoparticle, and began to grow into nanotubes.

“Our observations showed that the carbon atoms attached only to the pure metal facets of the cobalt carbide nanoparticle, and not those facets interlaced with carbon atoms,” says NIST chemist Renu Sharma, who led the research effort. “The burgeoning tube then grew above the cobalt-carbon facets until it found another pure metal surface to attach to, forming a closed cap. Carbon atoms continued to attach at the cobalt facets, pushing the previously formed graphene along toward the cap in a kind of carbon assembly line and lengthening the tube. This whole process took only a few seconds.”

According to Sharma, the carbon atoms seek out the most energetically favorable configurations as they form graphene on the cobalt carbide nanoparticle’s surface. While graphene has a mostly hexagonal, honeycomb-type structure, the geometry of the nanoparticle forces the carbon atoms to arrange themselves into pentagonal shapes within the otherwise honeycomb lattice. Crucially, these pentagonal irregularities in the graphene’s structure are what allows the graphene to curve and become a nanotube.

Because the nanoparticles’ facets also appear to play a deciding role in the nanotube’s diameter and chirality, or direction of twist, the group’s next step will be to measure the chirality of the nanotubes as they grow. The group also plans to use metal nanoparticles with different facets to study their adhesive properties to see how they affect the tubes’ chirality and diameter.

The researchers have made one of their movies available for viewing, but, despite my efforts, I cannot find a way to embed the silent movie. Happily, you can find the ‘baby carbon nanotube’ movie alongside NIST’s Dec. 1, 2014 NIST news release,

As for the research paper, here’s a link and a citation for it,

Nucleation of Graphene and Its Conversion to Single-Walled Carbon Nanotubes by Matthieu Picher, Pin Ann Lin, Jose L. Gomez-Ballesteros, Perla B. Balbuena, and Renu Sharma. Nano Lett., 2014, 14 (11), pp 6104–6108 DOI: 10.1021/nl501977b Publication Date (Web): October 20, 2014

Copyright © 2014 American Chemical Society

This paper is behind a paywall.

Shape-shifting bone material

Mammals of all kind have a horror disfigurement and will avoid members of their group who are disfigured. This horror is one of the themes to be found in the novel Frankenstein by Mary Shelley. Despite the difficulties, Roger Ebert (film critic) continued to make public appearances after cancer surgeries that changed his appearance (from a June 27, 2012 article by Ronni Gordon for Cancer Today),

Facing the Critics
Roger Ebert finds peace with his appearance following disfiguring cancer surgery

“Today I look like an exhibit in the Texas Chainsaw Museum,” he muses in his 2011 memoir, Life Itself. But Ebert decided he wasn’t going to hide the way he looks. In 2007, before attending his annual Overlooked Film Festival, now referred to as Ebertfest, at the University of Illinois at Urbana-Champaign, Ebert and his wife, Chaz, decided that a photograph of him should accompany a story he wrote for the Sun-Times. Later, he posed for a full-page photo that appeared in Esquire in March 2010.

“No point in denying it,” he wrote about his appearance in Life Itself. “No way to hide it. Better for it to be out there.”

Given the difficulties most people experience, researchers are eager to find solutions. An Aug. 13, 2014 American Chemical Society (ACS) news release (also on EurekAlert) describes a presentation at the ACS 284h meeting about shape-shifting material that could be used to ameliorate bone defects,

Injuries, birth defects (such as cleft palates) or surgery to remove a tumor can create gaps in bone that are too large to heal naturally. And when they occur in the head, face or jaw, these bone defects can dramatically alter a person’s appearance. Researchers will report today that they have developed a “self-fitting” material that expands with warm salt water to precisely fill bone defects, and also acts as a scaffold for new bone growth.

Currently, the most common method for filling bone defects in the head, face or jaw (known as the cranio-maxillofacial area) is autografting. That is a process in which surgeons harvest bone from elsewhere in the body, such as the hip bone, and then try to shape it to fit the bone defect.

“The problem is that the autograft is a rigid material that is very difficult to shape into these irregular defects,” says Melissa Grunlan, Ph.D., leader of the study. Also, harvesting bone for the autograft can itself create complications at the place where the bone was taken.

Another approach is to use bone putty or cement to plug gaps. However, these materials aren’t ideal. They become very brittle when they harden, and they lack pores, or small holes, that would allow new bone cells to move in and rebuild the damaged tissue.

To develop a better material, Grunlan and her colleagues at Texas A&M University made a shape-memory polymer (SMP) that molds itself precisely to the shape of the bone defect without being brittle. It also supports the growth of new bone tissue.

SMPs are materials whose geometry changes in response to heat. The team made a porous SMP foam by linking together molecules of poly(ε-caprolactone), an elastic, biodegradable substance that is already used in some medical implants. The resulting material resembled a stiff sponge, with many interconnected pores to allow bone cells to migrate in and grow.

Upon heating to 140 degrees Fahrenheit, the SMP becomes very soft and malleable. So, during surgery to repair a bone defect, a surgeon could warm the SMP to that temperature and fill in the defect with the softened material. Then, as the SMP is cooled to body temperature (98.6 degrees Fahrenheit), it would resume its former stiff texture and “lock” into place.

The researchers also coated the SMPs with polydopamine, a sticky substance that helps lock the polymer into place by inducing formation of a mineral that is found in bone. It may also help osteoblasts, the cells that produce bone, to adhere and spread throughout the polymer. The SMP is biodegradable, so that eventually the scaffold will disappear, leaving only new bone tissue behind.

To test whether the SMP scaffold could support bone cell growth, the researchers seeded the polymer with human osteoblasts. After three days, the polydopamine-coated SMPs had grown about five times more osteoblasts than those without a coating. Furthermore, the osteoblasts produced more of the two proteins, runX2 and osteopontin, that are critical for new bone formation.

Grunlan says that the next step will be to test the SMP’s ability to heal cranio-maxillofacial bone defects in animals. “The work we’ve done in vitro is very encouraging,” she says. “Now we’d like to move this into preclinical and, hopefully, clinical studies.”

The researchers acknowledge funding from the Texas A&M Engineering Experiment Station.

It sounds like there’s still quite a long way to go before this research makes its way out of the laboratory. I wish the researchers all the best.

A labradoodle, gold nanoparticles, and cancer treatment for dogs and cats

Here’s the labradoodle,

Caption: Dr. Shawna Klahn, an assistant professor of oncology at the Virginia-Maryland College of Veterinary Medicine, performs a checkup on "Grayton" four weeks after the animal's experimental cancer treatment involving gold nanoparticles and a targeted laser therapy. Credit: Virginia Tech

Caption: Dr. Shawna Klahn, an assistant professor of oncology at the Virginia-Maryland College of Veterinary Medicine, performs a checkup on “Grayton” four weeks after the animal’s experimental cancer treatment involving gold nanoparticles and a targeted laser therapy.
Credit: Virginia Tech

An Aug. 6, 2014 news item on Azonano outlines ‘Grayton’s’ story and how gold nanoparticles will factor in,

When Michael and Sandra Friedlander first came to the Virginia-Maryland College of Veterinary Medicine three years ago with their dog, Grayton, they learned some bad news: Grayton had nasal adenocarcinoma, a form of cancer with a short life expectancy.

“Most dogs with this form of cancer are with their owners no more than a few months after the diagnosis, but here Grayton is three years later,” said Michael Friedlander, who is the executive director of the Virginia Tech Carilion Research Institute and senior dean at the Virginia Tech Carilion School of Medicine.

No stranger to medical research, Friedlander was referred by Veterinary Teaching Hospital clinicians to an experimental treatment at the University of Florida called stereotactic radiation therapy, which delivers precise, high dosages of radiation to a tumor and can only be performed once.

“That shrunk the tumor down to almost nothing,” said Friedlander, who is also the associate provost for health sciences at Virginia Tech. “We knew when Grayton had the procedure that we couldn’t do it again, but now the cancer is back.”

An Aug. 4, 2014 Virginia Tech news release (also on EurekAlert) by Michael Sutphin, which originated the news item, explains what occasioned the release and how gold nanoparticles are being used in veterinary treatment for cancer,

Today [Aug. 4, 2014], the 11-year-old Labradoodle is the first patient at the Virginia-Maryland College of Veterinary Medicine in a new clinical trial that is testing the use of gold nanoparticles and a targeted laser treatment for solid tumors in dogs and cats. The study is one of several on new treatments for client-owned companion animals at the college. In January [2014], the college established the Veterinary Clinical Research Office to help facilitate this work.

“Clinical research at the veterinary college involves both primary research focused on advancing the treatment and diagnosis of veterinary diseases and translational research in which spontaneous diseases in animals can be used as models of human disease,” said Dr. Greg Daniel, head of the Department of Small Animal Clinical Sciences. “In the latter situation, we can provide our companion animal patients with treatment and diagnostic options that are not yet available in mainstream human medicine.”

Although medical researchers have tested gold nanoparticles with targeted laser treatments on human patients with some success, the treatment is still new to both human and veterinary medicine. The college is one of four current veterinary schools around the country testing the AuroLase therapy developed by Nanospectra Biosciences Inc., a startup company based in Houston, Texas. The others are Texas A&M University, the University of Wisconsin-Madison, and the University of Georgia.

Dr. Nick Dervisis, assistant professor of oncology in the Department of Small Animal Clinical Sciences, is leading the Nanospectra-funded study. Following a rhinoscopy performed on Grayton by Dr. David Grant, associate professor of internal medicine, Dervisis began the one-time, experimental therapy.

“The treatment involves two phases,” Dervisis said. “First, we infuse the patient with the gold nanoparticles. Although the nanoparticles distribute throughout the body, they tend to concentrate around blood vessels associated with tumors. Within 36 hours, they have cleared the bloodstream except for tumors. The gold nanoparticles are small enough to circulate freely in the bloodstream and become temporarily captured within the incomplete blood vessel walls common in solid tumors. Then, we use a non-ablative laser on the patient.”

Dervisis explained that a non-ablative laser is not strong enough to harm the skin or normal tissue, but “it does cause the remaining nanoparticles to absorb the laser energy and convert it into heat so that they damage the tumor cells.”

Like all clinical trials, the study involves many unknowns, including the treatment’s usefulness and effectiveness. One month after the AuroLase treatment, the nosebleeds that initially brought Grayton back to the Veterinary Teaching Hospital had stopped and Grayton has no other side effects.

“I’m delighted with the care and service that Grayton has received at the veterinary college,” said Friedlander, who explained that the treatment appears to be safe even though researchers do not know whether it is effective yet. “Grayton recently came with us on our annual vacation at the beach. We didn’t know if he would be able to come again, so it was great to have him with us swimming, catching fish and crabs, and doing what dogs do.”

Current clinical trials at the veterinary college range from the use of MRI to distinguish between benign and cancerous lymph nodes in dogs with oral melanoma, to a new chemotherapy drug for dogs with brain tumors, to the treatment of invasive skin cancer in horses with high-voltage, high-frequency electrical pulses. A complete list of current trials can be found at the college’s new clinical trials website.

Mindy Quigley, who oversees the college’s Veterinary Clinical Research Office, explained that veterinary trials, which follow a four-phase process and a variety of regulations similar to human medicine, have another layer of complexity that human trials do not.

“Variation among species means that a therapy that has proven safe and effective in, for example, humans or dogs, may not work for horses,” said Quigley, who comes to the college from the University of Edinburgh’s College of Medicine and Veterinary Medicine, where she helped set up a new neurology research clinic with funding from author J.K. Rowling. “Many veterinary clinical trials must therefore take therapies that have worked in one species and test them in other species with similar conditions. This is a necessary step to determine if a proposed treatment is safe and effective for our companion animals.”

Grayton may be the first companion animal in the AuroLase study at the veterinary college, but he certainly won’t be the last. Dervisis is continuing to enroll patients in the study and is seeking dogs and cats of a certain size with solid tumors who have not recently received radiation therapy or chemotherapy.

Interested parties can check this site for current clinical trials, including the Aurolase study,  being held by the Virginia-Maryland Regional College of Veterinary Medicine.

Sounds like fracking to me: research into unconventional hydrocarbon production at Texas A&M University

A July 29, 2013 news item on Nanowerk features a Flotek Industries-sponsored research initiative at Texas A&M University,

Flotek Industries, Inc. announced today sponsorship of applied research at Texas A&M University to investigate the impact of nanotechnology on oil and natural gas production in emerging, unconventional resource plays.

“With the acceleration of activity in oil and gas producing shales, a better understanding of the impact of various completion chemistries on tight formations with low porosity and permeability will be key to developing optimal completion techniques in the future,” said John Chisholm, Flotek’s Chairman, President and Chief Executive Officer. “While we know Flotek’s Complex nano-Fluid chemistries have been successful in enhancing production in tight resource formations, we believe a more complete understanding of the interaction between our chemistries and geologic formations as well as a more precise comprehension of the physical properties and impact of our nanofluids in the completion process will significantly enhance the efficacy of the unconventional hydrocarbon completion process. This research continues our relationship with Texas A&M where we also are conducting research into acidizing applications in Enhanced Oil Recovery.”

The words ‘unconventional’ and ‘shale’ in the context of oil and gas production suggest fracking to me. For anyone who’s unfamiliar with the practice, here’s an excerpt from a good description in a June 27, 2013 news item on the BBC (British Broadcasting Corporation) website,

What is fracking?

Fracking is the process of drilling down into the earth before a high-pressure water mixture is directed at the rock to release the gas inside. Water, sand and chemicals are injected into the rock at high pressure which allows the gas to flow out to the head of the well.

The process is carried out vertically or, more commonly, by drilling horizontally to the rock layer. The process can create new pathways to release gas or can be used to extend existing channels.

Why is it controversial?

The extensive use of fracking in the US, where it has revolutionised the energy industry, has prompted environmental concerns.

The first is that fracking uses huge amounts of water that must be transported to the fracking site, at significant environmental cost. The second is the worry that potentially carcinogenic chemicals used may escape and contaminate groundwater around the fracking site. The industry suggests pollution incidents are the results of bad practice, rather than an inherently risky technique.

The July 29, 2013 Flotek Industries news release (on PRNewswire’s heraldonline.com website) which originated the news item provides more details about the research initiative,

Specifically, the research will focus its investigation on the oil recovery potential of complex nanofluids and select surfactants under subsurface pressure and temperature conditions of liquids-rich shales.

Dr. I. Yucel Akkutlu, Associate Professor of Petroleum Engineering in the Harold Vance Department of Petroleum Engineering at Texas A&M University will serve as the principal investigator for the project. Dr. Akkutlu received his Masters and PhD in Petroleum Engineering from the University of Southern California. He has over a decade of postgraduate theoretical and experimental research experience in unconventional oil and gas recovery, enhanced oil recovery and reactive flow and transport in heterogeneous porous media. He has recently participated in industry-sponsored research on resource shales including analysis of microscopic data to better understand fluid storage and transport properties of organic-rich shales.

“As unconventional resource opportunities continue to grow in importance to hydrocarbon production, understanding ways to maximize recovery will be key to improving the efficacy of these projects,” said Dr. Akkutlu. “The key to enhancing recovery will be to best understand robust, new technologies and their impact on the completion process. Research into complex nanofluid chemistries to understand the physical properties and formation interactions will play an integral role in the future of completion design to optimize recovery from unconventional hydrocarbon resources.”

There was a little surprise (for me) on the website’s Our Company webpage,

Flotek’s vision is to be the premier energy services company focused on best-in class technology, cutting-edge innovation and exceptional customer service all standing in the support of our never-ending commitment to provide superior returns for our stakeholders. Flotek Industries Inc., is a diversified global supplier of drilling-and production-related products and services to the energy and mining industries. Flotek is headquartered in Houston, Texas and its common shares are traded on the New York Stock Exchange market under the stock ticker symbol, “FTK.” FLOTEK was originally incorporated under the laws of the Province of British Columbia on May 17, 1985. [emphasis mine] On October 23, 2001, we approved a change in our corporate domicile to the state of Delaware and a reverse stock split of 120 to 1. On October 31, 2001, we completed a reverse merger with CESI Chemical, Inc. (“CESI”). …

I wasn’t expecting the British Columbia (Canadian province where I live) connection.

Moving on to the nanotechnology connection, there’s this about the nano-fluid technology they use currently on the company’s homepage,

Chemical & Logistics / CESI Chemical

Complex nano-Fluid™ Technology

See how CESI Chemical’s patented CnF® will enhance hydrocarbon production and recovery and improve production economics in almost every completion scenario.

If you should visit the company website, expect to fill out a registration for any product information additional to what you see on the homepage or product index page.