Achieving a new method of nanoscopic imaging, the scientific team studied the myelin sheath, the membrane surrounding nerves that is compromised in patients with multiple sclerosis (MS). The study is published in this week's online edition of the Proceedings of the National Academy of Sciences (PNAS).
"Myelin membranes are a class of biological membranes that are only two molecules thick, less than one millionth of a millimeter," said Jacob Israelachvili, one of the senior authors and professor of chemical engineering and of materials at UCSB. "The membranes wrap around the nerve axons to form the myelin sheath."
He explained that the way different parts of the central nervous system, including the brain, communicate with each other throughout the body is via the transmission of electric impulses, or signals, along the fibrous myelin sheaths. The sheaths act like electric cables or transmission lines.
"Defects in the molecular or structural organization of myelin membranes lead to reduced transmission efficiency," said Israelachvilli. "This results in various sensory and motor disorders or disabilities, and neurological diseases such as multiple sclerosis."
At the microscopic level and the macroscopic level, which is visible to the eye, MS is characterized by the appearance of lesions or vacuoles in the myelin, and eventually results in the complete disintegration of the myelin sheath. This progressive disintegration is called demyelination.
The researchers focused on what happens at the molecular level, commonly referred to as the nanoscopic level. This requires highly sensitive visualization and characterization techniques.
The article describes fluorescence imaging and other measurements of domains, which are small heterogeneous clusters of lipid molecules –– the main constituents of myelin membranes –– that are likely to be responsible for the formation of lesions. They did this using model molecular layers in compositions that mimic both healthy and diseased myelin membranes.
They observed differences in the appearance, size, and sensitivity to pressure, of domains in the healthy and diseased monolayers. Next, they developed a theoretical model, in terms of certain molecular properties, that appears to account quantitatively for their observations.
"The discovery and characterization of micron-sized domains that are different in healthy and diseased lipid assemblies have important implications for the way these membranes interact with each other," said Israelachvili. "And this leads to new understanding of demyelination at the molecular level."
The findings pave the way for new experimental methods for early detection, diagnosis, staging, and possible treatment of pathological tissues that are precursors to MS and other membrane-associated diseases, according to the authors.
All of the work reported in the paper was completed at UCSB, although some of the authors have moved to other institutions. In addition to Israelachvili, the other authors are Dong Woog Lee, graduate student in UCSB's Department of Chemical Engineering; Younjin Min, now a postdoctoral fellow in the Department of Chemical Engineering at the Massachusetts Institute of Engineering; Prajnaparamitra Dhar, now assistant professor in the Department of Chemical Engineering at the University of Kansas; Arun Ramachandran, now assistant professor in the Department of Chemical Engineering and Applied Chemistry at the University of Toronto; and Joseph A. Zasadzinski, now professor in the Department of Chemical Engineering and Materials Science at the University of Minnesota.
Gail Gallessich | EurekAlert!
‘Farming’ bacteria to boost growth in the oceans
24.10.2016 | Max-Planck-Institut für marine Mikrobiologie
Calcium Induces Chronic Lung Infections
24.10.2016 | Universität Basel
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
24.10.2016 | Earth Sciences
24.10.2016 | Life Sciences
24.10.2016 | Physics and Astronomy