|
MediaNews Releases2010
Science HighlightsHealth: Shining Light on Brain Tumours 
Infrared spectromicroscopic images of brain tissue obtained by the CLS Mid-Infrared beamline. The dark blue mottling representing lipids (fats) in the healthy tissue (left) is largely absent from the GBM tumour (right). The Canadian Cancer Society estimates that 2600 new cases of brain cancer will be diagnosed in 2010. Glioblastoma multiforme (GBM) is the most aggressive and malignant form of brain cancer, and attempts to successfully treat GBM tumours depends on identifying tumour cells – both when detecting cancer in biopsies and when ensuring that all of the cancer has been removed after surgery. With the help of the Canadian Light Source, a team led by Dr. Kaiser Ali, a pediatric oncologist in the Saskatchewan Cancer Agency’s Cancer Research Unit and collaborators from the University of Saskatchewan, Saskatoon Health Region, CLS and the National Research Council have been able to identify a chemical signature unique to GBM tumour cells. The pilot study made the front cover of the July 2010 issue of the International Journal of Molecular Medicine. Reference: K. Ali, et al. 2010. Biomolecular diagnosis of glioblastoma multiforme using Synchrotron mid-infrared spectomicroscopy. International Journal of Molecular Medicine 26 pp. 11-16.
Materials: Synchrotron takes bearing on nano magnets 
Scanning transmission X-ray microscope image of bacterial cells taken at the CLS. The blue dots are iron-containing magnetosomes, each about 30 billionths of a metre in size. Image courtesy of Adam Hitchcock, McMaster University. Since the late 1960’s, scientists have known that some bacteria make internal compasses by growing tiny magnetic crystals called magnetosomes. The bacteria use them to navigate, with cells of the same species growing crystals of uniform size, structure and out of the same magnetic minerals. Using the Canadian Light Source, researchers have for the first time been able to ‘see’ the magnetism of magnetosomes inside individual bacterial cells using the synchrotron’s X-ray microscope. The finding sheds light on how magnetosomes grow in bacterial cells in response to genetic and environmental factors. Such understanding could be used by researchers to genetically manipulate the bacteria to grow magnetosomes that are tailor made for use in new kinds of data storage devices, nanomachines or delivery systems for cancer chemotherapy and other drug treatments. Reference: Lam, K.P., Hitchcock, A.P. et al. 2010. Characterizing magnetism of individual magnetosomes by X-ray magnetic circular dichroism in a scanning transmission X-ray microscope. Chemical Geology 270, pp. 110-116. DOI: 10.1016/j.chemgeo.2009.11.009
Materials: Synchrotron reaches for the stars 
Infrared spectrum of the Orion Nebula (background)—the first taken by the Herschel Space Observatory’s HIFI spectrometer in March, 2010. Infrared spectra taken at the CLS is helping astronomers make sense of spectra obtained by Herschel and other new telescopes. Interstellar clouds and other astronomical features are rich sources of organic chemicals. However, the pervasiveness of some molecules, such as methanol, drown out the spectral fingerprints of more exotic chemicals. With a new generation of space observatories and radio telescopes coming online, astronomers are plumbing the chemical depths of space with greater detail than ever before. But they have to be able to weed out the signals from methanol and other common molecules in order to see the rarer chemicals that may be out there. Using the CLS, researchers are building high-resolution spectral fingerprints of methanol in all its isotopic forms that can be applied to astronomers\’ incoming data Reference: R.M. Lees, R.-J. Murphy, G. Moruzzi, A. Predoi-Cross, L.-H. Xu, D.R.T. Appadoo, B. Billinghurst, R.R.J. Golding, S. Zhao. 2009. Fourier transform spectroscopy of the CO-stretching band of O-18 methanol. Journal of Molecular Spectroscopy, 256, pp. 91-98. DOI:10.1016/j.jms.2009.02.015
Health: Setting sights on new antibiotics 
Structural diagram of the UGM enzyme, derived from data collected at the CLS. This structural information is key to developing inhibitor compounds for new types of antibiotics. Image courtesy of David Sanders, University of Saskatchewan. Bacterial infections once thought to be on the verge of eradication have been making a comeback, like Mycobacterium tuberculosis, the bug that causes tuberculosis. The rate of antibiotics resistance is on the rise as bacteria become resistant faster than we can come up with new drugs. The problem is compounded by the fact that new antibiotics are usually developed by modifying existing ones. Thus, bacteria that become resistant to an antibiotic often also become resistant to other drugs in the same class. University of Saskatchewan researcher David Sanders is trying to buck this trend. Using the Canadian Light Source, Sanders and his team are undertaking work that may lead to the development of an entirely new class of antibiotics to which no bacteria have resistance by targeting the building blocks of the bacteria’s cell wall. Reference: S.K. Partha, K.E. van Straaten, D.A.R. Sanders, 2009. Structural Basis of Substrate Binding to UDP-galactopyranose Mutase: Crystal Structures in the Reduced and Oxidized State Complexed with UDP-galactopyranose and UDP. Journal of Molecular Biology, 394(5), pp. 864-77. DOI:10.1016/j.jmb.2009.10.013
Environment: Sulphur-eating bacteria limit acid run-off and CO2 
Composite map of different types of sulphur in a microbial pod (a) obtained at the ALS, along with a comparison of spectra from the various forms of sulphur compared to reference standards from the CLS (b). K. Norlund, McMaster University. Acid Mine Drainage (AMD) is caused when sulphur in mine tailings reacts with water and oxygen in the environment to produce sulphuric acid. It is a major environmental issue, with AMD a concern for lake acidification and water quality. AMD is also implicated as a climate change culprit – the sulphuric acid dissolves carbonate minerals in the underlying rock, liberating carbon dioxide in a process known as acid rock weathering. Using two beamlines at the Canadian Light Source (CLS) and a third at the Advanced Light Source (ALS), researchers from McMaster University have found that two species of bacteria isolated from a mine tailings pond in northern Ontario actually work together to limit the amount of acid produced by sharing the sulphur in the tailings as an energy source. Reference: Norlund et al. 2009. Microbial Architecture of Environmental Sulfur Processes: A Novel Syntrophic Sulfur-Metabolizing Consortia. Environmental Science and Technology 43, pp. 8781-8786.
Last modified: 2010-08-11 08:08:04 |
|||||||||||||||||||
| Site Map | Links | Webmaster | Disclaimer | Add Site to Favorites | Text Only Version |