bones – Lightsources.org

Promising new drug carrier could improve bone repair and cancer treatments

2020/07/142020/07/21

Researchers from Western University and the Shanghai Institute of Ceramics, Chinese Academy of Sciences used the Canadian Light Source (CLS) at the University of Saskatchewan to explore a promising drug carrier that could be used to deliver cancer treatments and therapeutics for severe injuries.

Their work advances drug carrier technology to make the carrier more compatible with our bodies. This allows the drug carrier to deliver the desired treatment precisely to a tumor, or to allow a slower release of the medicine. In a new paper published in The Royal Society of Chemistry, the team investigated using calcium phosphate as a potential drug carrier. Their approach uses phosphate from the biomolecule that stores and transports energy in our cells, which allows the carrier to be more compatible with the human body. Using this drug delivery system solves the limitations of other carriers, including biocompatibility and toxicity. Their carrier is highly compatible with our biological system, allowing for a better response while also being non-toxic.

“Calcium phosphate is an important biomaterial in bones and teeth. If you can use this material as a drug carrier then you don’t need to worry about what happens after it is done with delivery,” said Tsun-Kong (TK) Sham, Professor of Chemistry at Western University.

Read more on the Canadian Light Source website

Image: TK Sham, a Professor of Chemistry at Western University, using beamlines at the CLS.

Egyptian mummy bones explored with X-rays and infrared light

2019/11/122019/11/14

Researchers from Cairo University work with teams at Berkeley Lab’s Advanced Light Source to study soil and bone samples dating back 4,000 years.

Experiments at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) are casting a new light on Egyptian soil and ancient mummified bone samples that could provide a richer understanding of daily life and environmental conditions thousands of years ago.
In a two-monthslong research effort that concluded in late August, two researchers from Cairo University in Egypt brought 32 bone samples and two soil samples to study using X-ray and infrared light-based techniques at Berkeley Lab’s Advanced Light Source (ALS). The ALS produces various wavelengths of bright light that can be used to explore the microscopic chemistry, structure, and other properties of samples.
Their visit was made possible by LAAAMP – the Lightsources for Africa, the Americas, Asia and Middle East Project – a grant-supported program that is intended to foster greater international scientific opportunity and collaboration for scientists working in that region of the globe.

Image: From left, Cairo University postdoctoral researcher Mohamed Kasem, ALS scientist Hans Bechtel, and Cairo University associate professor Ahmed Elnewishy study bone samples at the ALS using infrared light.
Credit: Marilyn Sargent/Berkeley Lab

The active role of collagen in building bones

2019/08/292019/09/12

We use our skeleton every day, but our mental model of our bones may look more like a glow-in-the-dark Halloween costume, or a teaching skeleton hanging on a sitcom set, than true anatomy. While these common representations of skeletons focus on the sturdy aspects of bones, the structural frames of actual bones are built by a soft organic portion. To create bones, the human body precipitates calcium phosphate minerals using collagen, a long protein, as scaffolding. Our bodies mineralize calcium phosphate both inside and outside collagen-confined spaces, and scientists are still working to understand how the two types of mineralization occur. Recent research at the U.S. Department of Energy’s Advanced Photon Source (APS) has investigated mineralization rates and shown that collagen structures reduce the energy barriers to mineralization by providing a substrate on which the calcium phosphate can precipitate. Since common bone diseases, such as osteoporosis, hinge on an abnormal calcium phosphate precipitation process, this improved understanding of the role of collagen in precipitation could lead to insight into the treatment of these diseases.

Figure (extract, full image here) This scanning electron microscopy image shows calcium phosphate minerals nucleation in both extrafibrillar (purple colored image) and intrafibrillar (green colored image) spaces of collagen matrices. Without polyaspartic acid, extrafibrillar nucleation of calcium phosphate is dominant while with polyaspartic acid, intrafibrillar nucleation mainly occurs.

Research on shark vertebrae could improve bone disease treatment

2019/07/262019/07/31

The U.S. Department of Energy’s Advanced Photon Source (APS) at Argonne National Laboratory has facilitated tens of thousands of experiments across nearly every conceivable area of scientific research since it first saw light more than two decades ago.
But it wasn’t until earlier this year that the storied facility was used to study shark vertebrae in an experiment that one Northwestern University researcher hopes will shed light on the functionality of human bone and cartilage. Shark spines constantly flex when they swim, said Stuart R. Stock, a materials scientist and faculty member of Northwestern’s Feinberg School of Medicine. Yet they remain surprisingly resilient throughout the fish’s lifetime, he said.

Human bones, however, cannot endure the same kind of bending and become more fragile as people age. Stock is using the APS to better understand shark vertebrae’s formation and strength. He wants to know how the animal’s tissue develops and how it functions when the animal swims.

X-ray fluorescence sheds light on the growth patterns of extinct hyaena

2019/03/152019/03/18

A novel synchrotron technique examines growth patterns in fossil bones

Until recently, it was thought that warm-blooded animals experienced uninterrupted high rates of growth, whilst cold-blooded animals showed zonal growth – alternating periods of fast and slow growth. The identification of zonal growth in a range of mammals and birds disproved that theory, but as yet we don’t know how widespread zonal growth is in vertebrates, or which factors affect the speed of bone growth. Conventional techniques lack the resolution to correlate variations in bone chemistry with histological features, but in work recently published in the Journal of Analytical Atomic Spectrometry, an international team of researchers carried out the first direct comparison between optical histology (bone tissue identification) and synchrotron-based chemical mapping, quantification, and characterisation of trace elements (biochemistry) within cyclic growth tissues, and reported the first case of zonal tissue within the Hyaenidae.

Image: Lead author Jennifer Anné with a spotted hyaena mount.

Research shows how to improve the bond between implants and bone

2018/07/032018/07/05

Research carried out recently at the Canadian Light Source (CLS) in Saskatoon has revealed promising information about how to build a better dental implant, one that integrates more readily with bone to reduce the risk of failure.

“There are millions of dental and orthopedic implants placed every year in North America and a certain number of them always fail, even in healthy people with healthy bone,” said Kathryn Grandfield, assistant professor in the Department of Materials Science and Engineering at McMaster University in Hamilton.

A dental implant restores function after a tooth is lost or removed. It is usually a screw shaped implant that is placed in the jaw bone and acts as the tooth roots, while an artificial tooth is placed on top. The implant portion is the artificial root that holds an artificial tooth in place.

Grandfield led a study that showed altering the surface of a titanium implant improved its connection to the surrounding bone. It is a finding that may well be applicable to other kinds of metal implants, including engineered knees and hips, and even plates used to secure bone fractures.

About three million people in North America receive dental implants annually. While the failure rate is only one to two percent, “one or two percent of three million is a lot,” she said. Orthopedic implants fail up to five per cent of the time within the first 10 years; the expected life of these devices is about 20 to 25 years, she added.

“What we’re trying to discover is why they fail, and why the implants that are successful work. Our goal is to understand the bone-implant interface in order to improve the design of implants.”

Tungsten accumulation in bone raises health concerns

2018/04/172018/04/19

McGill University scientists have identified exposure to tungsten as problematic after they determined how and where high levels of the metal accumulate and remain in bone.

“Our research provides further evidence against the long-standing perception that tungsten is inert and non-toxic,” said Cassidy VanderSchee, a PhD student and a member of a McGill research group headed by chemistry professor Scott Bohle.

Tungsten is a hard metal with a high melting point and, when combined with other metals and used as an alloy, it’s also very flexible.

Because of these properties and under the assumption that tungsten is non-toxic, it has been tested for use in medical implants, including arterial stents and hip replacements, in radiation shields to protect tissue during radiation therapy, and in some drugs. Tungsten is found in ammunition as well as in tools used for machining and cutting other metals.

Tungsten also occurs naturally in groundwater where deposits of the mineral are found. Exposure to high levels of tungsten in drinking water in Fallon, Nevada, was investigated for a possible link with childhood leukemia in the early 2000s. This investigation lead scientists to question the long-held belief that exposure to tungsten is safe and prompted the Centers for Disease Control and Prevention in the U.S. to nominate tungsten for toxicology and carcinogenesis studies.

Image: Cassidy VenderSchee

Marianne Liebi winner of Swedish L’Oréal-Unesco For Women in Science 2018

2018/03/072018/03/15

L’Oréal-Unesco For Women in Science Prize is awarded in Sweden for the third time. The purpose of the prize is to pay attention to and reward young women who have shown great potential in science, while offering positive female role-models. Researchers Marianne Liebi, Chalmers, and Ruth Pöttgen, Lund University, get L’Oréal-Unesco For Women in Science Award, supported by Sweden’s young academy 2018.

Marianne Liebi gets the award “for the constructive use of advanced imaging methods for biomaterials with the aim of understanding the connection between molecular and mechanical properties”. Marianne Liebi uses powerful X-ray technology to study how, for example, the smallest building blocks, collagen fibrils, the bone tissue, look and are organised. The goal is to develop a mimicking, biomimetic material, where nature’s own design principles are imitated and applied to develop artificial bone and cartilage.
“It’s important to show that in research, it does not matter where you come from or who you are – what matters is passion and dedication. At best, this kind of award will not be needed in the future, it would be aimed at all young researchers. It would not matter who you were, says Marianne Liebi.

Photo: Researchers Ruth Pöttgen (left), Lund University, and Marianne Liebi (right), Chalmers, get L’Oréal-Unesco For Women in Science Award 2018, supported by Young Academy Sweden.
Credit: Emma Burendahl

A better quality of tomography images

2015/08/242018/01/16

A research group composed of Dr. Naoki Sunaguchi (Gunma University), Prof. Tetsuya Yuasa (Yamagata University), M.D. Rajiv Gupta (Massachusetts General Hospital), Shin-ichi Hirano (Mercian Cleantec Corporation, MiZ Company Limited), and Prof. Masami Ando (Tokyo University of Science and Emeritus Professor at KEK) developed a new algorithm to improve the quality of an X-ray phase-contrast image.

X-ray phase-contrast imaging can provide far higher contrast in soft tissue compared to classical absorption-based imaging. Many groups have been developing a variety of imaging methods for potential clinical use. All these imaging methods suffer from a common problem: severe imaging artefacts arise when x-ray phase alternation exceeds the dynamic range of the imaging system, typically in the vicinity of bones and dense calcifications. These artefacts are similar to the metal and beam-hardening artefacts seen in traditional attenuation-based X-ray computed tomography (CT) even though they tend to be more severe and have a different physical basis. A particularly worrisome part of this type of artifact is the fact that it spreads broadly across a wide area on CT image even when the dense tissue responsible for it localized.

Image: A rat foot model of rheumatoid arthritis. Left: Absorption image, Middle: Phase image using conventional algorithms, and Right: phase image employing the proposed algorithm. All images were taken at the BL-14C, Photon Factory, KEK.

Tag: bones