Optical detection of brain function: simultaneous imaging of cerebral vascular response, tissue metabolism, and cellular activity in vivo

2011 ◽  
Vol 22 (6) ◽  
Author(s):  
Congwu Du ◽  
Yingtian Pan
Keyword(s):  
Brain Function ◽  
Optical Detection ◽  
Cellular Activity ◽  
Vascular Response ◽  
Tissue Metabolism ◽  
Simultaneous Imaging ◽  
Cerebral Vascular

Implantable neural interfaces

2018 ◽  
Author(s):  
Stefano Vassanelli
Keyword(s):  
Brain Function ◽  
Large Scale ◽  
Ionic Channels ◽  
Patch Clamp Technique ◽  
Advantages And Disadvantages ◽  
Optogenetic Stimulation ◽  
Physical Interfaces ◽  
The Brain

Establishing direct communication with the brain through physical interfaces is a fundamental strategy to investigate brain function. Starting with the patch-clamp technique in the seventies, neuroscience has moved from detailed characterization of ionic channels to the analysis of single neurons and, more recently, microcircuits in brain neuronal networks. Development of new biohybrid probes with electrodes for recording and stimulating neurons in the living animal is a natural consequence of this trend. The recent introduction of optogenetic stimulation and advanced high-resolution large-scale electrical recording approaches demonstrates this need. Brain implants for real-time neurophysiology are also opening new avenues for neuroprosthetics to restore brain function after injury or in neurological disorders. This chapter provides an overview on existing and emergent neurophysiology technologies with particular focus on those intended to interface neuronal microcircuits in vivo. Chemical, electrical, and optogenetic-based interfaces are presented, with an analysis of advantages and disadvantages of the different technical approaches.

A Novel α-Conotoxin Identified by Gene Sequencing Is Active in Suppressing the Vascular Response to Selective Stimulation of Sensory Nerves in Vivo†

Biochemistry ◽  
2003 ◽  
Vol 42 (22) ◽  
pp. 6904-6911 ◽  
Author(s):  
D. W. Sandall ◽  
N. Satkunanathan ◽  
D. A. Keays ◽  
M. A. Polidano ◽  
X. Liping ◽  
...  
Keyword(s):  
Gene Sequencing ◽  
Sensory Nerves ◽  
Vascular Response ◽  
Selective Stimulation ◽  
Stimulation Of

scholarly journals Switchable control over in vivo CAR T expansion, B cell depletion, and induction of memory

2018 ◽  
Vol 115 (46) ◽  
pp. E10898-E10906 ◽  
Author(s):  
Sophie Viaud ◽  
Jennifer S. Y. Ma ◽  
Ian R. Hardy ◽  
Eric N. Hampton ◽  
Brent Benish ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
Rest Period ◽  
Cell System ◽  
Cellular Activity ◽  
Dosing Regimen ◽  
Car T Cells ◽  
Car T

Chimeric antigen receptor (CAR) T cells with a long-lived memory phenotype are correlated with durable, complete remissions in patients with leukemia. However, not all CAR T cell products form robust memory populations, and those that do can induce chronic B cell aplasia in patients. To address these challenges, we previously developed a switchable CAR (sCAR) T cell system that allows fully tunable, on/off control over engineered cellular activity. To further evaluate the platform, we generated and assessed different murine sCAR constructs to determine the factors that afford efficacy, persistence, and expansion of sCAR T cells in a competent immune system. We find that sCAR T cells undergo significant in vivo expansion, which is correlated with potent antitumor efficacy. Most importantly, we show that the switch dosing regimen not only allows control over B cell populations through iterative depletion and repopulation, but that the “rest” period between dosing cycles is the key for induction of memory and expansion of sCAR T cells. These findings introduce rest as a paradigm in enhancing memory and improving the efficacy and persistence of engineered T cell products.

scholarly journals The Middle Domain of Hsp90 Acts as a Discriminator between Different Types of Client Proteins

2006 ◽  
Vol 26 (22) ◽  
pp. 8385-8395 ◽  
Author(s):  
Patricija Hawle ◽  
Martin Siepmann ◽  
Anja Harst ◽  
Marco Siderius ◽  
H. Peter Reusch ◽  
...  
Keyword(s):  
Atp Hydrolysis ◽  
Mutational Analysis ◽  
Fold Increase ◽  
Cellular Protein ◽  
Hydrolysis Rate ◽  
Cellular Activity ◽  
Protein Levels ◽  
Middle Domain ◽  
Client Proteins

ABSTRACT The mechanism of client protein activation by Hsp90 is enigmatic, and it is uncertain whether Hsp90 employs a common route for all proteins. Using a mutational analysis approach, we investigated the activation of two types of client proteins, glucocorticoid receptor (GR) and the kinase v-Src by the middle domain of Hsp90 (Hsp90M) in vivo. Remarkably, the overall cellular activity of v-Src was highly elevated in a W300A mutant yeast strain due to a 10-fold increase in cellular protein levels of the kinase. In contrast, the cellular activity of GR remained almost unaffected by the W300A mutation but was dramatically sensitive to S485Y and T525I exchanges. In addition, we show that mutations S485Y and T525I in Hsp90M reduce the ATP hydrolysis rate, suggesting that Hsp90 ATPase is more tightly regulated than assumed previously. Therefore, the activation of GR and v-Src has various demands on Hsp90 biochemistry and is dependent on separate functional regions of Hsp90M. Thus, Hsp90M seems to discriminate between different substrate types and to adjust the molecular chaperone for proper substrate activation.

scholarly journals On the correspondence of electrical and optical physiology in in vivo population-scale two-photon calcium imaging

2019 ◽  
Author(s):  
Peter Ledochowitsch ◽  
Lawrence Huang ◽  
Ulf Knoblich ◽  
Michael Oliver ◽  
Jerome Lecoq ◽  
...  
Keyword(s):  
Calcium Imaging ◽  
Biophysical Model ◽  
Data Set ◽  
Two Photon ◽  
Simultaneous Imaging ◽  
Fluorescence Measurements ◽  
Large Populations ◽  
Intractable Problem ◽  
Mouse Lines

AbstractMultiphoton calcium imaging is commonly used to monitor the spiking of large populations of neurons. Recovering action potentials from fluorescence necessitates calibration experiments, often with simultaneous imaging and cell-attached recording. Here we performed calibration for imaging conditions matching those of the Allen Brain Observatory. We developed a novel crowd-sourced, algorithmic approach to quality control. Our final data set was 50 recordings from 35 neurons in 3 mouse lines. Our calibration indicated that 3 or more spikes were required to produce consistent changes in fluorescence. Moreover, neither a simple linear model nor a more complex biophysical model accurately predicted fluorescence for small numbers of spikes (1-3). We observed increases in fluorescence corresponding to prolonged depolarizations, particularly in Emx1-IRES-Cre mouse line crosses. Our results indicate that deriving spike times from fluorescence measurements may be an intractable problem in some mouse lines.

scholarly journals Assessing Variations in Areal Organization for the Intrinsic Brain: From Fingerprints to Reliability

2016 ◽  
Author(s):  
Ting Xu ◽  
Alexander Opitz ◽  
R. Cameron Craddock ◽  
Margaret Wright ◽  
Xi-Nian Zuo ◽  
...  
Keyword(s):  
Individual Variation ◽  
Brain Function ◽  
Intraclass Correlation ◽  
Resting State Fmri ◽  
Single Individual ◽  
Initial Application ◽  
Novel Approach ◽  
Gradient Based ◽  
Healthy Participants

AbstractResting state fMRI (R-fMRI) is a powerful in-vivo tool for examining the functional architecture of the human brain. Recent studies have demonstrated the ability to characterize transitions between functionally distinct cortical areas through the mapping of gradients in intrinsic functional connectivity (iFC) profiles. To date, this novel approach has primarily been applied to iFC profiles averaged across groups of individuals, or in one case, a single individual scanned multiple times. Here, we used a publically available R-fMRI dataset, in which 30 healthy participants were scanned 10 times (10 minutes per session), to investigate differences in full-brain transition profiles (i.e., gradient maps, edge maps) across individuals, and their reliability. 10-minute R-fMRI scans were sufficient to achieve high accuracies in efforts to “fingerprint” individuals based upon full-brain transition profiles. Regarding testretest reliability, the image-wise intraclass correlation coefficient (ICC) was moderate, and vertex-level ICC varied depending on region; larger durations of data yielded higher reliability scores universally. Initial application of gradient-based methodologies to a recently published dataset obtained from twins suggested inter-individual variation in areal profiles might have genetic and familial origins. Overall, these results illustrate the utility of gradient-based iFC approaches for studying inter-individual variation in brain function.

scholarly journals Two-Photon Laser-Scanning Microscopy for Single and Repetitive Imaging of Dorsal and Lateral Spinal White Matter In Vivo

2017 ◽  
pp. 531-537 ◽  
Author(s):  
F. NADRIGNY ◽  
K. LE MEUR ◽  
E. D. SCHOMBURG ◽  
S. SAFAVI-ABBASI ◽  
P. DIBAJ
Keyword(s):  
White Matter ◽  
Laser Scanning ◽  
Dorsal Column ◽  
Minimal Invasive ◽  
Laser Scanning Microscopy ◽  
Intravenous Anesthesia ◽  
Two Photon ◽  
Simultaneous Imaging ◽  
Volatile Anesthesia

We developed appropriate surgical procedures for single and repetitive multi-photon imaging of spinal cord in vivo. By intravenous anesthesia, artificial ventilation and laminectomy, acute experiments were performed in the dorsal and lateral white matter. By volatile anesthesia and minimal-invasive surgery, chronic repetitive imaging up to 8 months was performed in the dorsal column through the window between two adjacent spines. Transgenic mouse technology enabled simultaneous imaging of labeled axons, astrocytes and microglia. Repetitive imaging showed positional shifts of microglia over time. These techniques serve for investigations of cellular dynamics and cell-cell interactions in intact and pathologically changed spinal tissue.

scholarly journals Fluorescence modeling of in vivo optical detection of Mycobacterium tuberculosis

2019 ◽  
Vol 10 (10) ◽  
pp. 5445 ◽  
Author(s):  
Madeleine S. Durkee ◽  
Jeffrey D. Cirillo ◽  
Kristen C. Maitland
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Optical Detection

Mapping vascular response to in vivo Hemodynamics: application to increased flow at the basilar terminus

2010 ◽  
Vol 9 (4) ◽  
pp. 421-434 ◽  
Author(s):  
Markus Tremmel ◽  
Jianping Xiang ◽  
Yiemeng Hoi ◽  
John Kolega ◽  
Adnan H. Siddiqui ◽  
...  
Keyword(s):  
Vascular Response
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