A5089565033- Ultrasound Imaging and Elastography
- Photoacoustic and Ultrasonic Imaging
- Neural dynamics and brain function
- Advanced MRI Techniques and Applications
- Ultrasound and Hyperthermia Applications
- Neuroscience and Neural Engineering
- Photoreceptor and optogenetics research
- Ultrasonics and Acoustic Wave Propagation
- Neuroscience and Neuropharmacology Research
- Retinal Development and Disorders
- Electrical and Bioimpedance Tomography
- Elasticity and Material Modeling
- Memory and Neural Mechanisms
- Functional Brain Connectivity Studies
- Visual perception and processing mechanisms
- Coal Combustion and Slurry Processing
- Material Properties and Applications
- Hearing Loss and Rehabilitation
- Polymer Science and Applications
- Botulinum Toxin and Related Neurological Disorders
- Environmental and Industrial Safety
- Protein Structure and Dynamics
- Lipid Membrane Structure and Behavior
- Optical Imaging and Spectroscopy Techniques
- Facial Rejuvenation and Surgery Techniques
Max Planck Institute for Biological Intelligence
2022-2024
Nanoscale Microscopy and Molecular Physiology of the Brain Cluster of Excellence 171 — DFG Research Center 103
2023-2024
Universitätsmedizin Göttingen
2023-2024
University of Göttingen
2023-2024
University Medical Center
2024
European Neuroscience Institute Göttingen
2023
Max Planck Institute of Neurobiology
2020-2022
Max Planck Institute of Biochemistry
2022
Friedrich Miescher Institute
2015-2019
Institute of Molecular and Clinical Ophthalmology Basel
2018
Hemodynamic changes in the brain are often used as surrogates of neuronal activity to infer loci activity. A major limitation conventional Doppler ultrasound for imaging these is that it not sensitive enough detect blood flow small vessels where part hemodynamic response occurs. Here, we present a μDoppler method able and map cerebral volume (CBV) over entire with an important increase sensitivity. This based on at ultrafast frame rate (1 kHz) using compounded plane wave emissions....
General anesthetics induce loss of consciousness, a global change in behavior. However, corresponding activity the context defined cortical cell types has not been identified. Here, we show that spontaneous mouse layer 5 pyramidal neurons, but no other type, becomes consistently synchronized vivo by different general anesthetics. This heightened neuronal synchrony is aperiodic, present across large distances, and absent neurons presynaptic to neurons. During transition from anesthesia,...
Most inherited retinal dystrophies display progressive photoreceptor cell degeneration leading to severe visual impairment. Optogenetic reactivation of neurons mediated by adeno-associated virus (AAV) gene therapy has the potential restore vision regardless patient-specific mutations. The challenge for clinical translatability is a as close natural possible, while using surgically safe delivery route fragile degenerated retina. To preserve processing inner retina, we targeted ON bipolar...
Research Article27 September 2016Open Access Transparent process Red-shifted channelrhodopsin stimulation restores light responses in blind mice, macaque retina, and human retina Abhishek Sengupta INSERM, U968, Paris, France Sorbonne Universités, UPMC Univ Paris 06, UMR_S 968, Institut de la Vision, CNRS, UMR_7210, Search for more papers by this author Antoine Chaffiol Emilie Macé Romain Caplette Mélissa Desrosiers Maruša Lampič Valérie Forster Olivier Marre John Y Lin School of Medicine,...
The majority of inherited retinal degenerations converge on the phenotype photoreceptor cell death. Second- and third-order neurons are spared in these diseases, making it possible to restore light responses using optogenetics. Viral expression channelrhodopsin under ubiquitous promoters was previously shown visual function, albeit at intensities above illumination safety thresholds. Here, we report (to our knowledge, for first time) activation macaque retinas, up 6 months post-injection,...
Highlights•Functional ultrasound enables imaging whole-brain activity during mouse behavior•Activity in 87 brain regions are modulated the optokinetic reflex•Reflex-related were identified by perturbing retinal direction selectivity•A subset of these regions, all thalamus, independent eye motionSummaryLarge numbers active behaviors. A high-resolution, brain-wide map could identify involved specific We have developed functional to record behaving mice at a resolution ∼100 μm. detected visual...
Neuronal activity can be modulated by mechanical stimuli. To study this phenomenon quantitatively, we mechanically stimulated rat cortical neurons shear stress and local indentation. Neurons show 2 distinct responses, classified as transient sustained. Transient responses display fast kinetics, similar to spontaneous neuronal activity, whereas sustained last several minutes before returning baseline. Local soma stimulations with micrometer-sized beads evoke at low forces of ∼220 nN pressures...
Abstract Midface rejuvenation is among the most valuable indications of hyaluronic acid dermal fillers, because malar projection and full upper cheeks significantly contribute to a youthful appearance. Hyaluronic fillers have evolved over past 2 decades meet specific clinical needs such as strong capacity adaptability facial dynamism. As result, they now represent treatment choice for midface throughout age ranges by offering potential noninvasive treatment, immediate results, minimal...
Functional ultrasound imaging is a method recently developed to assess brain activity via hemodynamics in rodents. Doppler signals allow the measurement of cerebral blood volume (CBV) and red cells' (RBCs') velocity small vessels. However, this technique originally requires performing large craniotomy that limits its use acute experiments only. Moreover, detailed description hemodynamic changes underlie functional has not been described but essential for better interpretation neuroimaging...
A combination of radiation force and ultrafast ultrasound imaging is used to both generate track the propagation a shear wave in brain whose local speed directly related stiffness, characterized by dynamic modulus G*. When performed on trepanated rats, this approach called (SWI) provides 3-D elasticity maps reaching spatial resolution 0.7 mm×1 mm×0.4 mm with good reproducibility (<13%). The tissues exhibits values 2-25 kPa range mean value 12 quantified for different anatomical regions....
Blood flow interruption in a cerebral artery causes brain ischemia and induces dramatic changes of perfusion metabolism the corresponding territory. We performed parallel positron emission tomography (PET) with [ 15 O]H 2 O, single photon computed (SPECT) 99m Tc]hexamethylpropylene-amino-oxime ([ Tc]HMPAO) ultrasonic ultrafast shear wave imaging (SWI) during, immediately after, 1, 2, 4, 7 days after middle occlusion (MCAO) rats. Positron SPECT showed initial hypoperfusion followed by...
In the early visual system, cells of same type perform computation in different places field. How these code together a complex scene is unclear. A common assumption that single-type extract single-stimulus feature to form map, but this has rarely been observed directly. Using large-scale recordings rat retina, we show homogeneous population fast OFF ganglion simultaneously encodes two radically features scene. Cells close moving object quasilinearly for its position, while distant remain...
Neuroscientists studying the neural correlates of mouse behavior often lack access to brain-wide activity patterns elicited during a specific task interest. Fortunately, large-scale imaging is becoming increasingly accessible thanks modalities such as Ca2+ and functional ultrasound (fUS). However, these other techniques involve challenging cranial window procedures are difficult combine with neuroscience tools. We address this need an open-source 3D-printable implant-the COMBO (ChrOnic...
Red blood cell velocity (RBCv), cerebral flow (CBF), and volume (CBV) are three key parameters when describing brain hemodynamics. Functional ultrasound imaging is a Doppler-based method allowing for real-time measurement of relative CBV at high spatiotemporal resolution (100 × 110 300 μm
We have investigated the phase behavior of DPPC (dipalmitoylphosphatidylcholine) monolayers at water−air interface using molecular dynamics simulations, where phospholipids and water molecules are modeled atomistically. report pressure−area isotherms in interval 273−310 K. Our results show evidence for a liquid condensed (LC) to expanded (LE) transition indicate that ordered phases can nucleate from starting disordered on time scale approximately 50 ns. The existence is confirmed with...
This work applies the concept of compounded plane wave transmissions at very high frames rates some KHz for ultrafast Doppler analysis over a large region interest. As this compound imaging method has similar quality to standard focusing but is 10 times faster, it possible generate fast images frame 300Hz. rate able visualize transient phenomena and display duplex modes with simultaneous color spectrum each pixel image. The interest not restricted velocity flows; by optimizing ultrasonic...