Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Determining ion beam effects to greater precision: Researchers conduct high-res analyses on lesions in tissue

23.09.2015

A precise understanding of how ion beams affect biological tissue is of great importance for both radiotherapy applications and the assessment of radioprotection risks, e.g. to astronauts on long term missions in space. The radiation biology and biophysics research groups headed by Professor Markus Löbrich (TU Darmstadt) and Professor Marco Durante (GSI) respectively were the first to conduct experimental high resolution analyses on the 3D lesion distribution induced by high energy ion beams in biological tissue and to compare these with theoretical model predictions.

The biological effects of radiation consist in the damage caused to genetic information (DNA) contained in every cell nucleus. However, cells feature powerful repair mechanisms that can undo a lot of the damage caused by radiation.


Scientists from Darmstadt were the first to analyse 3D lesion distribution in biological tissue on the submicrometre level. Picture: Thanh Nguyen

That ion beams can induce greater effects than conventional photon (e.g. X ray) radiation can be explained by the extremely high energy they emit over a very small space around the ions’ path. In other words, ion beams can induce highly complex local damage that is far more resistant to repair efforts than the damage caused by photon radiation.

The conceptions favoured to date of ion beam induced 3D lesion patterns are based above all on theoretical considerations deduced from measurements of physical properties. There are no measurement data available for biological systems.

In a joint research project, scientists at the TU Darmstadt and GSI Hemholtzzentrum für Schwerionenforschung were the first to analyse 3D lesion distribution in biological tissue on the submicrometre level and to compare their findings with theoretical predictions. The radiation experiments at GSI used high energy ion beams with the same characteristics as the cosmic radiation in space.

Identification with marker

The analyses were conducted on a tissue with a particularly high density of cell nuclei, facilitating a virtually continuous detection of DNA damage. The identification of damage involved the use of a marker for the most serious form of biological damage, the DNA double strand break, causing the irreversible loss of key genetic information. This experimental approach can visualise the traces of ion induced DNA damage over many cells. The measurements show clearly the concentration of damage at the centre of the ion path and a rapidly declining lesion frequency away from this.

Effects predicted to greater precision

On the one hand, these biological findings confirm the assumptions of 3D lesion distribution based on measured physical properties. On the other, they can be used for a critical analysis and quasi calibration of the various prediction models. These data provide an essential constituent of a model for the prediction of radiation efficacy that was developed by GSI physicists and applied for treatment planning at the ion beam therapy centres in Heidelberg, Marburg, Pavia, and Shanghai for their tumour treatment schedules.

Further information
All details can be found in “Direct Measurement of the 3-Dimensional DNA Lesion Distribution Induced by Energetic Charged Particles in a Mouse Model Tissue” by Johanna Mirsch, Francesco Tommasino, Antonia Frohns, Sandro Conrad, Marco Durante, Michael Scholz, Thomas Friedrich, and Markus Löbrich published in the Proceedings of the National Academy of Sciences of the United States of America (PNAS):
http://www.pnas.org/content/early/2015/09/17/1508702112.abstract

MI-Nr. 62e/2015, ml/feu

Weitere Informationen:

http://www.pnas.org/content/early/2015/09/17/1508702112.abstract publication online

Silke Paradowski | Technische Universität Darmstadt
Further information:
http://www.tu-darmstadt.de/

More articles from Physics and Astronomy:

nachricht Water without windows: Capturing water vapor inside an electron microscope
13.12.2017 | Okinawa Institute of Science and Technology (OIST) Graduate University

nachricht Columbia engineers create artificial graphene in a nanofabricated semiconductor structure
13.12.2017 | Columbia University School of Engineering and Applied Science

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Protein Structure Could Unlock New Treatments for Cystic Fibrosis

14.12.2017 | Life Sciences

Cardiolinc™: an NPO to personalize treatment for cardiovascular disease patients

14.12.2017 | Life Sciences

ASU scientists develop new, rapid pipeline for antimicrobials

14.12.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>