Standard light microscopes don't allow researchers to look into the interior of the living brain, where memories are formed and diseases such as dementia and cancer can take their toll.
But Stanford scientists have devised a new method that not only lets them peer deep inside the brain to examine its neurons but also allows them to continue monitoring for months.
The technique promises to improve understanding of both the normal biology and diseased states of this hidden tissue.
Other recent advances in micro-optics had enabled scientists to take a peek at cells of the deep brain, but their observations captured only a momentary snapshot of the microscopic changes that occur over months and years with aging and illness.The Stanford development appears online Jan. 16 in the journal Nature Medicine. It also will appear in the February 2011 print edition.
"Researchers will now be able to study mouse models in these deep areas in a way that wasn't available before," said senior author Mark Schnitzer, associate professor of biology and of applied physics.
Because light microscopy can only penetrate the outermost layer of tissues, any region of the brain deeper than 700 microns or so (about 1/32 of an inch) cannot be reached by traditional microscopy techniques. Recent advances in micro-optics had allowed scientists to briefly peer deeper into living tissues, but it was nearly impossible to return to the same location of the brain and it was very likely that the tissue of interest would become damaged or infected.With the new method, "Imaging is possible over a very long time without damaging the region of interest," said Juergen Jung, operations manager of the Schnitzer lab. Tiny glass tubes, about half the width of a grain of rice, are carefully placed in the deep brain of an anaesthetized mouse. Once the tubes are in place, the brain is not exposed to the outside environment, thus preventing infection. When researchers want to examine the cells and their interactions at this site, they insert a tiny optical instrument called a microendoscope inside the glass guide tube. The guide tubes have glass windows at the ends through which scientists can examine the interior of the brain.
To test the use of the technique for investigating brain disease, the researchers looked at a mouse model of glioma, a deadly form of brain cancer. They saw hallmarks of glioma growth in the deep brain that were previously known in tumors described as surficial (on or near the surface).
The severity of glioma tumors depends on their location. "The most aggressive brain tumors arise deep and not superficially," said Lawrence Recht, professor of neurology and neurological sciences. Why the position of glioma tumors affects their growth rate isn't understood, but this method would be a way to explore that question, Recht said.
In addition to continuing their studies of brain disease and the neuroscience of memory, the researchers hope to teach other researchers how to perform the technique.
The first three authors of the paper (all of whom contributed equally to the study) are Robert Barretto, a former doctoral student in biophysics and now a postdoctoral researcher at Columbia University Medical Center; Tony Ko, a former postdoctoral researcher in the Department of Biology; and Jung. Also contributing to the work – and listed as authors – are Tammy Wang, a former undergraduate in biomedical engineering; George Capps and Allison Waters, both former undergraduates in biology; and Yaniv Ziv and Alessio Attardo, both postdoctoral researchers in biology.
Louis Bergeron | EurekAlert!
Self-powered paper-based 'SPEDs' may lead to new medical-diagnostic tools
23.08.2017 | Purdue University
New technique to treating mitral valve diseases: First patient data
22.08.2017 | Universitätsspital Bern
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
23.08.2017 | Life Sciences
23.08.2017 | Life Sciences
23.08.2017 | Physics and Astronomy