LAST PUBLICATIONS

Stay tuned ! Look at our most recent publications and technological advances in neuroscience/neuroimaging.

Follow us on twitter @opto_brain_imag

INTERESTED IN FUS IMAGING ?

Functional UltraSound (fUS) is an innovative technology for imaging brain activity at high spatiotemporal resolution (80 um, 20 ms).

fUS is sensitive enough to detect blood flow in very small vessels in the entire depth of the brain and without the need for contrast agents.

Please contact us if you want to evaluate all advantages of fUS technology for your research projects. Email: alan.urban@alan-urban.fr

For more informations, see the corresponding Menu at the top of this page.

IMAGING OF BRAIN DISEASES

Brain Imaging includes different methods that fall into two broad categories: structural and functional imaging. Structural imaging investigates the structure of the brain and can be used for the diagnosis of large-scale intracranial diseases such as tumors, and injuries.

Functional imaging reveals the activity in certain brain regions by detecting changes in metabolism, blood flow, regional chemical composition and/or absorption. The major challenge in the years ahead will be to combine both real-time and non-invasive brain imaging.

Brain imaging technologies are crucial for understanding the relationships between specific areas of the brain and their function, helping to locate the areas of the brain that are affected by diseases or neurological disorders and build new strategies to treat them. 

 UNDERSTANDING THE BRAIN THROUGH INNOVATIVE IMAGING TECHNOLOGIES

Rapidly apply insights gained from model organisms to human health 

To better understand the normal brain, we are studying pathologies including stroke, psychiatric diseases, pain and epilepsy serving as models of brain circuit dysfunction. Our team seeks to accelerate the development of the breakthrough technologies to build versatile and costless tools to image brain activity and brain networks at both micro and macro-scales.

To address the challenges presented by neuroimaging, we develop a broad, interdisciplinary and translational science based on our own expertise and fruitfull collaborations with scientists, industries and citizens from all around the world.

These pages also aim at providing basic information on optogenetics, in vivo brain imaging and recording of electrical activity. Please use the top menu to navigate through the pages.

Our main research interests are summarized below:

 

If you require any further information, please feel free to contact meThis email address is being protected from spambots. You need JavaScript enabled to view it.

Note that this website is under construction (some menu links are not yet available) and will be updated soon.

 

TWITTER 

Alan URBAN
Our recent review on functional ultrasound imaging and 2P imaging is available online. https://t.co/gzv5I4VoPA https://t.co/m9PIcyl9xU
Alan URBAN
The results of the European Contest for Young Scientists are announced soon ! Good luck to the 2 French teams… https://t.co/GI2LNH8uwf
Alan URBAN
Starting of Eucys contest for young scientists in Estonia. The NERF R&D is inside a drone to measure pollution… https://t.co/N6BQ8Z70wX
Alan URBAN
RT @ac_chenus: Reportage diffusé hier sur #TF1 juste avant le départ pour #EUCYS @Sciences_Ecole @Fond_CGenial @opto_brain_imag https://t…
Alan URBAN
Our project DustrackR wins the first price of the Cgenial contest. Welcome EUCYS and happy birthday cgenial… https://t.co/5tCA8uwXhq
Alan URBAN
Our drone to quantify more precisely microparticules pollution is at the final of the C.genial contest! @imec_int @Fond_CGenial #urbanlab
Alan URBAN
functional ultrasound imaging: Quantitative measurement of Red Blood Cell velocity in the Berlin BrainPET meeting… https://t.co/uyjD7GTZIT
Follow Alan URBAN on Twitter

 

LAST PUBLICATIONS 

JCBFM - Functional UltraSound in a stroke model

JCBFM - Functional UltraSound in a stroke model

Functional ultrasound imaging efficiently mapped the acute changes in relative cerebral blood volume during occlusion and following reperfusion with high spatial resolution (100 mm), notably documenting marked focal decreases during occlusion, and was able to chart the fine dynamics of tissue reperfusion in the individual rat.

Read more →
Nature Methods - Functional UltraSound in freely moving rodents

Nature Methods - Functional UltraSound in freely moving rodents

Freely moving functional ultrasound (fm-fUS) imaging to image brain circuits in behaving rodents. fm-fUS can also efficiently decode brain activity in cortical and subcortical area during specific tasks.

Read more →
NeuroImage - Functional UltraSound in chronic conditions

NeuroImage - Functional UltraSound in chronic conditions

To overcome the limitation of the craniotomy, we developed a dedicated thinned skull surgery for chronic functional ultrasound imaging.

Read more →
JMTM - Functional UltraSound in humans

JMTM - Functional UltraSound in humans

Here we demonstrate how functional ultrasound can image brain capillaries in rodents and to visualize the cortical microvasculature in the human brain during neurosurgery.

Read more →
Molecular Psychiatry - Interneurons Classification

Molecular Psychiatry - Interneurons Classification

In collaboration with the Allen Brain Institute, our study demonstrate that a specific class of parvalbumin expressing interneurons may be involved in brain plasticity.

Read more →

A multidisciplinary team

Our team combines a set of unique expertise including neurobiology, brain imaging, physics/acoustics, computer-science, molecular biology, pharmacology and more for understanding brain function.

Open Source Technologies

We make all technologies freely available for the scientific community. As soon as results are published, we release all protocols, codes and hardware to allow everyone to use technologies from our lab.

Translational Research

Translational research helps turn early-stage innovations into new health products, advancing the innovation to the point where it becomes attractive for further development by the medical industry or healthcare agencies. See our last patents.

RESEARCH AND DEVELOPMENT 

Our research is focused on research and development of innovative technologies to better understand neural circuits and brain physiology.

We are currently working on 2 breakthrough imaging modalities that have been designed to become a centerpiece in both preclinical and clinical studies as it can be used to diagnose metabolic diseases and lesions on a finer scale, for neurological and cognitive psychological research as well as brain-computer interfaces.    

  • Functional ultrasound imaging (fUSi) = Imaging of brain hemodynamic activity at mesoscopic scale in the entire depth of the brain 

Structural images of brain vasculature and blood flow

Functional ultrasound (fUS) is a novel imaging modality able to measure cerebral blood volume (CBV), red blood cells velocity (RBC-V) and cerebral blood flow (CBF) that are key parameters to quantify hemodynamic variations observed during functional activation of the brain.

 Brain activity in real-time during somatosensory stimuli

Alternate right/left forepaw/whiskers stimulations

(the movie is accelerated 4 times)

  • Voltage Sensitive Dye imaging (VSDi) = Imaging of brain electrical activity locally at the surface of the brain

 Optical imaging of neurons depolarizations at the ms time-scale

Cortical Spreading Depression

(the movie is accelerated 60 times)

Also known as potentiometric dyes, VSD are dyes which change their spectral properties in response to voltage changes. They are able to provide linear measurements of firing activity of single neurons, large neuronal populations or cardiomyocytes. Many others physiological processes are accompanied by changes in cell membrane potential which can be detected with VSD. Measurements may indicate the site of action potential origin, and measurements of action potential velocity and direction may be obtained.

OUR LAB IN INTERNATIONAL CONGRESS & EVENTS 

Research-Oriented, Results-Driven: Spotlighting the Latest Developments in Cerebral Blood Flow, Metabolism & Function and PET

 

COME TO VISIT OUR POSTER

Functional Ultrasound (fUS) imaging of brain hemodynamics in a rat middle-cerebral artery occlusion (MCAo) model of selective neuronal loss (SNL) mimicking transient ischemic attack (TIA)

Clément BRUNNER1,*, Clothilde ISABEL1,*, Abraham MARTIN2, Clara DUSSAUX1, Anne SAVOYE1, Gabriel MONTALDO1, Jean-Claude BARON1,+ and Alan URBAN1,+
* co-first
+ co-last

1 Centre de Psychiatrie et Neurosciences, INSERM U894, Hôpital Sainte-Anne, Optogenetics and Brain Imaging, Stroke Research Team, Paris, 75014, France.

2 Molecular Imaging Unit, CICbiomaGUNE, Paseo Miramon 182, San Sebastian, Spain.

Objectives: SNL is a known outcome of brief MCAo in rodents, affecting mainly the striatum or cortex with proximal and distal MCAo, respectively [1]. SNL is important as it might also occur after TIAs, potentially impacting the cognitive and plastic ‘reserve’. However, both the behavioral and tissue perfusion changes underlying to SNL are scarcely understood so far. For this reason, we used fUS, a new imaging for chronic whole-brain mapping of cerebral blood volume with high spatiotemporal resolution (CBV)[2].  

Methods: Eight adult Sprague-Dawley rats were subjected to 45 minutes MCAo with reperfusion under 1.5% isoflurane and 100% oxygen. Four sham rats were used as controls. fUS data were acquired through previously thinned skull serially before, during and at 3 and 6 days after reperfusion. Ipsilateral/contralateral CBV ratios (CBVr) were computed for a template of atlas-based cytoarchitectonic ROIs modified from [3]. The Neuroscore and subtle sensorimotor functions (modified Sticky Label test and Beam Walking test) were assessed before and serially after tMCAo. Brains were collected at day 21 for immunofluorescence (IF) using NeuN, Iba1 and GFAP.

Results: We observed a marked (>50%) reduction in CBVr in the MCA territory during occlusion in 7/8 rats (one rat with no CBVr decrease was excluded from further analysis). Maximal CBVr reduction affected the somatosensory cortex (79±13% relative to baseline; p<0.0001). At 15 minutes after reperfusion, CBVr returned to near-baseline and followed , then to normal thereafter (p<0.05,). No statistical significant behavioral effects emerged across the group at any time point. No changes in CBVr or behavior were present in sham rats. There was marked striatal SNL (associated with moderate microglial activation and marked astrocytosis) in 6/8 MCAo rats vs 0/4 sham (p<0.05), whereas mild cortical SNL was found in 4/8 MCAo rats vs 1/4 sham (NS). There was no correlation among CBV, behavioral scores and IF lesion volumes in cortical areas.

Conclusions: This study shows the feasibility of fUS to serially map CBV during and days following MCAo. Little cortical SNL occurred despite marked initial rCBV reductions, however,  mostly striatal SNL no behavioral effects, as also reported for infarcts [5]; and iv) SNL is a frequent sequelae of brief MCAo in rodents that likely also occurs after TIAs, with potential clinical and therapeutic relevance.

[1] J.C. Baron et al, JCBFM, 34 (2014) 2-18.

[2] A. Urban et al, Neuroimage, 101 (2014) 138-49.

[3] J.L. Hughes et al, Neuroimage, 49 (2010) 19-31.

[4] Ejaz S. et al, Stroke (in press)

[5] S. Wegener et al, J Magn Reson Imaging, 21 (2005) 340-6.

 http://brain.kenes.com 

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