3-D Traction Microscopy

colprojMetastases occur when tumour cells detach from the primary tumour and migrate to distant sites through the connective tissue of organs. During this migration process, the tumour cells generate mechanical forces in order to overcome the resistance of the connective tissue or to change their shape so they can pass through very small pores.  In the current issue of the journal Nature Methods*, we describe a method for measuring the mechanical forces of tumour cell as they migrate through artificial connective tissue made of collagen, which mimics the natural matrix of organs in terms of its chemical composition, structure and other material properties. The idea behind the method is simple: we first measure the deformation of the connective tissue around the migrating cells. If the elasticity of the connective tissue is known, it can then be used like a spring scale to calculate the cell forces from the tissue deformations.

A particular challenge was that connective tissue is initially soft when forces are weak, but stiffens at the level of forces generated by tumour cells.  Tumour cells also use part of their forces to elongate into a spindle-like shape, allowing them to migrate at a remarkable speed even through very small pores of the connective tissue. In a next step, we will apply this method to investigate differences in the cell forces between differently aggressive tumours.

*doi: 10.1038/nmeth.3685

link to the press release statement from medicalnewstoday

Method in madness of migrating tumor cells

Search and rescue teams routinely use Bayesian updating to track down crashed airplanes or sunken ships: they draw a map with a first guess of the most probable locations and then continuously update the probability map as new information comes in. Physicists from the University of Erlangen-Nuremberg describe in the current issue of Nature Communications how Bayesian updating can be applied to moving objects even when they slowly or abruptly change their behavior.The researchers tracked migrating tumor cells through an artificial tissue matrix and discovered that the cells frequently switch their migration mode, but over time a distinct pattern in the Bayesian probability map emerged. Like a fingerprint, this pattern was specific for different environments in which the tumor cells migrated. The authors suggest that this fingerprint can be used as a diagnostic marker of tumor aggressiveness.

Click to download in FLV format (2.3MB)

The results have been published in Nature Communications (link to article)

 

audioslides

Nadine has finally uploaded her audioslides explaining her latest findings published in Acta Biomat from January this year.

coverslideActaBiomat2015

Traffic jams lend insight into Emperor penguins’ huddle

Emperor penguins are able to maintain the tight huddle that protects them from the harsh conditions of an Antarctic winter with stop-and-go movements like cars in a traffic jam.

Click to download in FLV format (33.83MB)

Read more: Traffic jams lend insight into Emperor penguins’ huddle

Penguin-Observatory (SPOT)

Penguin Observatory is on the move to Antarctica

Our penguin observatory is on the research vessel "Polarstern"  on its way to Antarctica.  It will arrive there around Dec 20th. We hope that the observatory will not be battered too much by braking waves. 

atkaspot penguin observatory on research vessel Polarstern

Read more: Penguin-Observatory (SPOT)

Cancer mechanics highlight in Nature

NatureOutlook2012Our work on cancer cell contractility was highlighted in Nature (Nature 491, S56–S57, 22 November 2012).  Erika Jonietz summarizes current views and opinions of different scientists on the importance of cancer cell mechanics as a diagnostic tool and its potential as a therapeutic target. Our view is that cancer cell mechanics is complicated - there is no universal mechanical pattern or marker that distinguishes cancer cells from non-cancerous cells.  But we still believe that understanding cancer cell mechanics holds an important key for understanding cancer cell metastasis and is therefore worth pursuing. 

Optical Imaging Center Erlangen is open

The University of Erlangen now has its own Center for Optical Imaging. It will contain a core facility unit that provides state-of-the-art commercial solutions for optical imaging for biomedical research, materials science, physics, and other researchers that rely on optical imaging. The imaging facilites will include pool of ~ 10 microscopes, including laser scanning confocal, two-photon, and spinning disk microscopes as well dark-field, phase contrast, super resolution and fluorescence microscopes for various applications. The facility will be run by a dedicated team of scientific and technical staff. Current head of the imaging center is Dr. Ralf Palmisano, Max Planck Institute for the Science of Light, Günther Scharowsky Str. 1, 91058 Erlangen, Phone: +49-9131-6877-227.

More information under http://www.oice.uni-erlangen.de/

It’s not only strength, direction also counts in cancer cell invasion

To metastasize, cancer cells “muscle” their way through tissue, but some highly metastatic cells make particularly efficient use of force. 

 

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Read more: It’s not only strength, direction also counts in cancer cell invasion

Anymals.org jetzt online!

anymals.org - ein freies Anwendungsprogramm (App) für Mobiltelefone zur Darstellung und Erfassung lokaler Biodiversität

Daniel P. Zitterbart

Das Verschwinden von Arten aus ihren angestammten Lebenräumen, oder das Einschleppen fremder Arten durch die Globalisierung, bleiben oftmals unerkannt, obwohl einzelne Naturbeobachter das sehr wohl bemerkt haben, aber ihr Wissen nicht weitergeleitet wird.  Endlich können Naturfreunde ihre Beobachtungen von Tieren und Pflanzen der größten Datenbank für wissenschaftliche Auswertungen zur Verfügung stellen. Alles, was sie dazu benötigen, ist ein Smartphone. 

Read more: Anymals.org jetzt online!

penguin huddling dynamics

Keeping warm: coordinated movements in a penguin huddle

To survive temperatures below -50 ° C and gale-force winds above 180 km/h during the Antarctic winter, Emperor penguins  form tightly packed huddles and, as has recently been discovered – the penguins actually coordinate their movements to give all members of the huddle a chance to warm up.

Penguin huddle with computer tracking

Read more: penguin huddling dynamics