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Neuroscience and Neurobiology

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Full-Text Articles in Medicine and Health Sciences

Distributions Of Hypothalamic Neuron Populations Co-Expressing Tyrosine Hydroxylase And The Vesicular Gaba Transporter In The Mouse., Kenichiro Negishi, Mikayla A. Payant, Kayla S. Schumacker, Gabor Wittman, Rebecca M. Butler, Ronald M. Lechan, Harry W. M. Steinbusch M, Arshad M. Khan, Melissa J. Chee Aug 2019

Distributions Of Hypothalamic Neuron Populations Co-Expressing Tyrosine Hydroxylase And The Vesicular Gaba Transporter In The Mouse., Kenichiro Negishi, Mikayla A. Payant, Kayla S. Schumacker, Gabor Wittman, Rebecca M. Butler, Ronald M. Lechan, Harry W. M. Steinbusch M, Arshad M. Khan, Melissa J. Chee

Arshad M. Khan, Ph.D.

No abstract provided.


Parsing The Behavioral And Brain Mechanisms Of Third-Party Punishment, Owen D. Jones, Matthew Ginther, Richard J. Bonnie, Morris B. Hoffman, Francis X. Shen, Kenneth W. Simons, Rene Marois Apr 2019

Parsing The Behavioral And Brain Mechanisms Of Third-Party Punishment, Owen D. Jones, Matthew Ginther, Richard J. Bonnie, Morris B. Hoffman, Francis X. Shen, Kenneth W. Simons, Rene Marois

Owen Jones

The evolved capacity for third-party punishment is considered crucial to the emergence and maintenance of elaborate human social organization and is central to the modern provision of fairness and justice within society. Although it is well established that the mental state of the offender and the severity of the harm he caused are the two primary predictors of punishment decisions, the precise cognitive and brain mechanisms by which these distinct components are evaluated and integrated into a punishment decision are poorly understood.

Using a brain-scanning technique known as functional magnetic resonance imaging (fMRI), we implemented a novel experimental design to …


Common Parietal Activation In Musical Mental Transformations Across Pitch And Time, Nicholas E.V. Foster, Andrea Halpern, Robert J. Zatorre Jun 2018

Common Parietal Activation In Musical Mental Transformations Across Pitch And Time, Nicholas E.V. Foster, Andrea Halpern, Robert J. Zatorre

Andrea Halpern

We previously observed that mental manipulation of the pitch level or temporal organization of melodies results in functional activation in the human intraparietal sulcus (IPS), a region also associated with visuospatial transformation and numerical calculation. Two outstanding questions about these musical transformations are whether pitch and time depend on separate or common processing in IPS, and whether IPS recruitment in melodic tasks varies depending upon the degree of transformation required (as it does in mental rotation). In the present study we sought to answer these questions by applying functional magnetic resonance imaging while musicians performed closely matched mental transposition (pitch …


Rumination Is Associated With Diminished Performance Monitoring, Ema Tanovic, Greg Hajack, Charles A. Sanislow Aug 2017

Rumination Is Associated With Diminished Performance Monitoring, Ema Tanovic, Greg Hajack, Charles A. Sanislow

Charles A. Sanislow, Ph.D.

Rumination is a construct that cuts across a variety of disorders, including anxiety and depression. It has been associated with deficits in cognitive control thought to confer risk for psychopathology. One aspect of cognitive control that is especially relevant to the content of ruminative thoughts is error processing. We examined the relation of rumination and 2 electrophysiological indices of error processing, error related negativity (ERN), an early index of error detection, and error positivity (Pe), a later index of error awareness. Consistent with prior work, ERN was negatively correlated with anxiety (i.e., more anxious individuals were characterized by larger ERNs). …


Effects Of Anandamide Administration On Components Of Reward Processing, Howard C. Cromwell May 2017

Effects Of Anandamide Administration On Components Of Reward Processing, Howard C. Cromwell

Howard Casey Cromwell

Previous research has implicated the positive modulation of anandamide, an endocannabinoid neurotransmitter,on feeding behavior. Anandamide is particularly noteworthy as it acts as an endogenous ligand of the CB1receptor, the same receptor that is activated by tetrahydrocannabinol, the primary psychoactive component in Cannabis sativa. Cannabis legalization in North America has presented with a need to study endocannabinoid agonists and their effects on behavior. Much has yet to be determined in terms of the role of the endocannabinoid system in decision-making scenarios. The research presented here tested the hypothesis that anandamide wouldaugment motivation and reward processing via appetitive and …


Multi-Scale Motility Amplitude Associated With Suicidal Thoughts In Major Depression, Premananda Indic, Greg Murray, Carlo Maggini, Mario Amore, Tiziana Meschi, Loris Borghi, Ross J. Baldessarini, Paola Salvatore Mar 2017

Multi-Scale Motility Amplitude Associated With Suicidal Thoughts In Major Depression, Premananda Indic, Greg Murray, Carlo Maggini, Mario Amore, Tiziana Meschi, Loris Borghi, Ross J. Baldessarini, Paola Salvatore

Premananda Indic

Major depression occurs at high prevalence in the general population, often starts in juvenile years, recurs over a lifetime, and is strongly associated with disability and suicide. Searches for biological markers in depression may have been hindered by assuming that depression is a unitary and relatively homogeneous disorder, mainly of mood, rather than addressing particular, clinically crucial features or diagnostic subtypes. Many studies have implicated quantitative alterations of motility rhythms in depressed human subjects. Since a candidate feature of great public-health significance is the unusually high risk of suicidal behavior in depressive disorders, we studied correlations between a measure (vulnerability …


Neurobiology Of The Premonitory Urge In Tourette's Syndrome: Pathophysiology And Treatment Implications, Andrea E. Cavanna, Kevin J. Black, Mark Hallett, Valerie Voon Dec 2016

Neurobiology Of The Premonitory Urge In Tourette's Syndrome: Pathophysiology And Treatment Implications, Andrea E. Cavanna, Kevin J. Black, Mark Hallett, Valerie Voon

Kevin J. Black, MD

Motor and vocal tics are relatively common motor manifestations identified as the core features of Tourette's syndrome (TS). Although traditional descriptions have focused on objective phenomenological observations, such as anatomical location, number and frequency of tics, patients' first-person accounts have consistently reported characteristic subjective correlates. These sensory phenomena are often described as a feeling of mounting inner tension or urge to move ("premonitory urge"), which is transiently relieved by tic expression. This article reviews the existing literature on the clinical and neurobiological aspects of the premonitory urge in patients with TS, with focus on its pathophysiology and possible treatment implications.


Therapeutic Raavrh10 Mediated Sod1 Silencing In Adult Sod1(G93a) Mice And Nonhuman Primates, Florie Borel, Gwladys Gernoux, Brynn Cardozo, Jake P. Metterville, Gabriela Toro Cabrera, Lina Song, Qin Su, Guang Ping Gao, Mai K. Elmallah, Robert H. Brown Jr., Christian Mueller Aug 2016

Therapeutic Raavrh10 Mediated Sod1 Silencing In Adult Sod1(G93a) Mice And Nonhuman Primates, Florie Borel, Gwladys Gernoux, Brynn Cardozo, Jake P. Metterville, Gabriela Toro Cabrera, Lina Song, Qin Su, Guang Ping Gao, Mai K. Elmallah, Robert H. Brown Jr., Christian Mueller

Christian Mueller

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease; survival in ALS is typically 3-5 years. No treatment extends patient survival by more than three months. Approximately 20% of familial ALS and 1-3% of sporadic ALS patients carry a mutation in the gene encoding superoxide dismutase 1 (SOD1). In a transgenic ALS mouse model expressing the mutant SOD1(G93A) protein, silencing the SOD1 gene prolongs survival. One study reports a therapeutic effect of silencing the SOD1 gene in systemically treated adult ALS mice; this was achieved with a short hairpin RNA, a silencing molecule that has raised multiple safety concerns, and …


Rescuing Perishable Neuroanatomical Information From A Threatened Biodiversity Hotspot: Remote Field Methods For Brain Tissue Preservation Validated By Cytoarchitectonic Analysis, Immunohistochemistry, And X-Ray Microcomputed Tomography, Daniel F. Hughes, Ellen M. Walker, Paul M. Gignac, Anais Martinez, Kenichiro Negishi, Carl S. Lieb, Eli Greenbaum, Arshad M. Khan May 2016

Rescuing Perishable Neuroanatomical Information From A Threatened Biodiversity Hotspot: Remote Field Methods For Brain Tissue Preservation Validated By Cytoarchitectonic Analysis, Immunohistochemistry, And X-Ray Microcomputed Tomography, Daniel F. Hughes, Ellen M. Walker, Paul M. Gignac, Anais Martinez, Kenichiro Negishi, Carl S. Lieb, Eli Greenbaum, Arshad M. Khan

Arshad M. Khan, Ph.D.

Biodiversity hotspots, which harbor more endemic species than elsewhere on Earth, are
increasingly threatened. There is a need to accelerate collection efforts in these regions
before threatened or endangered species become extinct. The diverse geographical, ecological,
genetic, morphological, and behavioral data generated from the on-site collection of
an individual specimen are useful for many scientific purposes. However, traditional methods
for specimen preparation in the field do not permit researchers to retrieve neuroanatomical
data, disregarding potentially useful data for increasing our understanding of brain
diversity. These data have helped clarify brain evolution, deciphered relationships between
structure and function, and revealed constraints …


Elucidation Of The Anatomy Of A Satiety Network: Focus On Connectivity Of The Parabrachial Nucleus In The Adult Rat, Györgyi Zséli, Barbara Vida, Anais Martinez, Ronald M. Lechan, Arshad M. Khan, Csaba Fekete Feb 2016

Elucidation Of The Anatomy Of A Satiety Network: Focus On Connectivity Of The Parabrachial Nucleus In The Adult Rat, Györgyi Zséli, Barbara Vida, Anais Martinez, Ronald M. Lechan, Arshad M. Khan, Csaba Fekete

Arshad M. Khan, Ph.D.

We hypothesized that brain regions showing neuronal activation after refeeding comprise major nodes in a satiety network, and tested this hypothesis with two sets of experiments. Detailed c-Fos mapping comparing fasted and refed rats was performed to identify candidate nodes of the satiety network. In addition to well-known feeding-related brain regions such as the arcuate, dorsomedial, and paraventricular hypothalamic nuclei, lateral hypothalamic area, parabrachial nucleus (PB), nucleus of the solitary tract and central amygdalar nucleus, other referring activated regions were also identified, such as the parastrial and parasubthalamic nuclei. To begin to understand the connectivity of the satiety network, the …


Human Cryptochrome Exhibits Light-Dependent Magnetosensitivity, Lauren Foley, Robert Gegear, Steven Reppert Dec 2015

Human Cryptochrome Exhibits Light-Dependent Magnetosensitivity, Lauren Foley, Robert Gegear, Steven Reppert

Robert J. Gegear

Humans are not believed to have a magnetic sense, even though many animals use the Earth's magnetic field for orientation and navigation. One model of magnetosensing in animals proposes that geomagnetic fields are perceived by light-sensitive chemical reactions involving the flavoprotein cryptochrome (CRY). Here we show using a transgenic approach that human CRY2, which is heavily expressed in the retina, can function as a magnetosensor in the magnetoreception system of Drosophila and that it does so in a light-dependent manner. The results show that human CRY2 has the molecular capability to function as a light-sensitive magnetosensor and reopen an area …


Defining Behavioral And Molecular Differences Between Summer And Migratory Monarch Butterflies, Haisun Zhu, Robert Gegear, Amy Casselman, Sriramana Kanginakudru, Steven Reppert Dec 2015

Defining Behavioral And Molecular Differences Between Summer And Migratory Monarch Butterflies, Haisun Zhu, Robert Gegear, Amy Casselman, Sriramana Kanginakudru, Steven Reppert

Robert J. Gegear

BACKGROUND: In the fall, Eastern North American monarch butterflies (Danaus plexippus) undergo a magnificent long-range migration. In contrast to spring and summer butterflies, fall migrants are juvenile hormone deficient, which leads to reproductive arrest and increased longevity. Migrants also use a time-compensated sun compass to help them navigate in the south/southwesterly direction en route for Mexico. Central issues in this area are defining the relationship between juvenile hormone status and oriented flight, critical features that differentiate summer monarchs from fall migrants, and identifying molecular correlates of behavioral state. RESULTS: Here we show that increasing juvenile hormone activity to induce summer-like …


The Iscore Predicts Health Care Costs Early After Hospitalization For Acute Ischemic Stroke, Gustavo Saposnik Oct 2015

The Iscore Predicts Health Care Costs Early After Hospitalization For Acute Ischemic Stroke, Gustavo Saposnik

Gustavo Saposnik

No abstract provided.


The Fly Camta Transcription Factor Potentiates Deactivation Of Rhodopsin, A G Protein-Coupled Light Receptor, Junhai Han, Ping Gong, Keith Reddig, Mirna Mitra, Peiyi Guo, Hong-Sheng Li Jul 2015

The Fly Camta Transcription Factor Potentiates Deactivation Of Rhodopsin, A G Protein-Coupled Light Receptor, Junhai Han, Ping Gong, Keith Reddig, Mirna Mitra, Peiyi Guo, Hong-Sheng Li

Peiyi Guo

Control of membrane-receptor activity is required not only for the accuracy of sensory responses, but also to protect cells from excitotoxicity. Here we report the isolation of two noncomplementary fly mutants with slow termination of photoresponses. Genetic and electrophysiological analyses of the mutants revealed a defect in the deactivation of rhodopsin, a visual G protein-coupled receptor (GPCR). The mutant gene was identified as the calmodulin-binding transcription activator (dCAMTA). The known rhodopsin regulator Arr2 does not mediate this visual function of dCAMTA. A genome-wide screen identified five dCAMTA target genes. Of these, overexpression of the F box gene dFbxl4 rescued the …


Mutation Of A Tadr Protein Leads To Rhodopsin And Gq-Dependent Retinal Degeneration In Drosophila, Lina Ni, Peiyi Guo, Keith Reddig, Mirna Mitra, Hong-Sheng Li Jul 2015

Mutation Of A Tadr Protein Leads To Rhodopsin And Gq-Dependent Retinal Degeneration In Drosophila, Lina Ni, Peiyi Guo, Keith Reddig, Mirna Mitra, Hong-Sheng Li

Peiyi Guo

The Drosophila photoreceptor is a model system for genetic study of retinal degeneration. Many gene mutations cause fly photoreceptor degeneration, either because of excessive stimulation of the visual transduction (phototransduction) cascade, or through apoptotic pathways that in many cases involve a visual arrestin Arr2. Here we report a gene named tadr (for torn and diminished rhabdomeres), which, when mutated, leads to photoreceptor degeneration through a different mechanism. Degeneration in the tadr mutant is characterized by shrunk and disrupted rhabdomeres, the light sensory organelles of photoreceptor. The TADR protein interacted in vitro with the major light receptor Rh1 rhodopsin, and genetic …


Minding The Aging Brain: Are We Ready For Personalized Medicine?, Jason Karlawish, Robert C. Green Jun 2015

Minding The Aging Brain: Are We Ready For Personalized Medicine?, Jason Karlawish, Robert C. Green

Robert A. Green

No abstract provided.


Argonaute Protein Identity And Pairing Geometry Determine Cooperativity In Mammalian Rna Silencing, Jennifer Broderick, William Salomon, Sean Ryder, Neil Aronin, Phillip Zamore May 2015

Argonaute Protein Identity And Pairing Geometry Determine Cooperativity In Mammalian Rna Silencing, Jennifer Broderick, William Salomon, Sean Ryder, Neil Aronin, Phillip Zamore

Sean P. Ryder

Small RNAs loaded into Argonaute proteins direct silencing of complementary target mRNAs. It has been proposed that multiple, imperfectly complementary small interfering RNAs or microRNAs, when bound to the 3' untranslated region of a target mRNA, function cooperatively to silence target expression. We report that, in cultured human HeLa cells and mouse embryonic fibroblasts, Argonaute1 (Ago1), Ago3, and Ago4 act cooperatively to silence both perfectly and partially complementary target RNAs bearing multiple small RNA-binding sites. Our data suggest that for Ago1, Ago3, and Ago4, multiple, adjacent small RNA-binding sites facilitate cooperative interactions that stabilize Argonaute binding. In contrast, small RNAs …


Use Of Telemedicine To Increase Thrombolysis And Advance Care In Acute Ischemic Stroke, Nils Henninger, Nabi Chowdhury, Marc Fisher, Majaz Moonis Apr 2015

Use Of Telemedicine To Increase Thrombolysis And Advance Care In Acute Ischemic Stroke, Nils Henninger, Nabi Chowdhury, Marc Fisher, Majaz Moonis

Nils Henninger

The use of the only proven therapy for acute ischemic stroke, intravenous tissue plasminogen activator (tPA), remains disappointingly low. One potential way to increase the use of tPA is by the implementation of telemedicine stroke care networks. Preliminary data from several studies indicate that the safe and expanded use of tPA for ischemic stroke can be accomplished with the help of telemedicine. Telemedicine stroke care networks can also be used in the future to enhance stroke diagnosis with advanced CT and MRI technology and to potentially increase the number of patients referred to tertiary stroke centers for intra-arterial therapies. It …


Comparison Between Coated Vs. Uncoated Suture Middle Cerebral Artery Occlusion In The Rat As Assessed By Perfusion/Diffusion Weighted Imaging, James Bouley, Marc Fisher, Nils Henninger Apr 2015

Comparison Between Coated Vs. Uncoated Suture Middle Cerebral Artery Occlusion In The Rat As Assessed By Perfusion/Diffusion Weighted Imaging, James Bouley, Marc Fisher, Nils Henninger

Nils Henninger

Differences among models in the temporal evolution of ischemia after middle cerebral artery occlusion (MCAO) in rats may considerably influence the results of experimental treatment studies. Using diffusion and perfusion imaging, we compared the spatiotemporal evolution of ischemia in Sprague-Dawley rats after permanent MCAO (pMCAO) with different types of sutures. Male Sprague-Dawley rats were randomly assigned to pMCAO produced with either 4-0 silicone coated (n=8), or 3-0 uncoated monofilaments (n=8). Serial determination of quantitative cerebral blood flow (CBF) and apparent diffusion coefficient (ADC) maps were performed up to 3 h after pMCAO. Lesion volumes were calculated by using previously validated …


Characterizing Tissue Fate After Transient Cerebral Ischemia Of Varying Duration Using Quantitative Diffusion And Perfusion Imaging, Juergen Bardutzky, Qiang Shen, Nils Henninger, Stefan Schwab, Timothy Duong, Marc Fisher Apr 2015

Characterizing Tissue Fate After Transient Cerebral Ischemia Of Varying Duration Using Quantitative Diffusion And Perfusion Imaging, Juergen Bardutzky, Qiang Shen, Nils Henninger, Stefan Schwab, Timothy Duong, Marc Fisher

Nils Henninger

BACKGROUND AND PURPOSE: The purpose of this study was to investigate the effects of reperfusion on ischemic lesion evolution and pixel-by-pixel apparent diffusion coefficient-cerebral blood flow (ADC-CBF) dynamics of core and mismatch tissues after 35, 60, and 95 minutes of transient focal ischemia in rats (n=28). METHODS: Serial diffusion-, perfusion-, and T2-weighted imaging were performed up to 24 hours. The evolution of the magnetic resonance image-derived lesion volume was investigated and ADC-CBF scatterplots were performed to prospectively characterize the ADC and CBF dynamics of core and mismatch tissues with different fates. For comparison, similar analysis was performed on a historical …


Comparison Of Ischemic Lesion Evolution In Embolic Versus Mechanical Middle Cerebral Artery Occlusion In Sprague Dawley Rats Using Diffusion And Perfusion Imaging, Nils Henninger, Kenneth Sicard, Karl Schmidt, Juergen Bardutzky, Marc Fisher Apr 2015

Comparison Of Ischemic Lesion Evolution In Embolic Versus Mechanical Middle Cerebral Artery Occlusion In Sprague Dawley Rats Using Diffusion And Perfusion Imaging, Nils Henninger, Kenneth Sicard, Karl Schmidt, Juergen Bardutzky, Marc Fisher

Nils Henninger

BACKGROUND AND PURPOSE: Differences among models in the temporal evolution of ischemia after middle cerebral artery occlusion (MCAO) in rats may considerably influence the results of experimental stroke research. Using diffusion and perfusion imaging, we compared the spatiotemporal evolution of ischemia in Sprague Dawley rats after permanent suture MCAO (sMCAO; n=8) and embolic MCAO (eMCAO; n=8).

METHODS: Serial measurements of quantitative cerebral blood flow (CBF) and the apparent diffusion coefficient (ADC) were performed up to 180 minutes after MCAO. ADC and CBF values within 5 different brain regions were analyzed. ADC and CBF lesion volumes were calculated by using previously …


Ischemic Lesion Volume Determination On Diffusion Weighted Images Vs. Apparent Diffusion Coefficient Maps, Bernt Bratane, Birgül Bastan, Marc Fisher, James Bouley, Nils Henninger Apr 2015

Ischemic Lesion Volume Determination On Diffusion Weighted Images Vs. Apparent Diffusion Coefficient Maps, Bernt Bratane, Birgül Bastan, Marc Fisher, James Bouley, Nils Henninger

Nils Henninger

Though diffusion weighted imaging (DWI) is frequently used for identifying the ischemic lesion in focal cerebral ischemia, the understanding of spatiotemporal evolution patterns observed with different analysis methods remains imprecise. DWI and calculated apparent diffusion coefficient (ADC) maps were serially obtained in rat stroke models (MCAO): permanent, 90 min, and 180 min temporary MCAO. Lesion volumes were analyzed in a blinded and randomized manner by 2 investigators using (i) a previously validated ADC threshold, (ii) visual determination of hypointense regions on ADC maps, and (iii) visual determination of hyperintense regions on DWI. Lesion volumes were correlated with 24 hour 2,3,5-triphenyltetrazoliumchloride …


The Proteasome Inhibitor Velcade Reduces Infarction In Rat Models Of Focal Cerebral Ischemia, Nils Henninger, Kenneth Sicard, James Bouley, Marc Fisher, Nancy Stagliano Apr 2015

The Proteasome Inhibitor Velcade Reduces Infarction In Rat Models Of Focal Cerebral Ischemia, Nils Henninger, Kenneth Sicard, James Bouley, Marc Fisher, Nancy Stagliano

Nils Henninger

The potential neuroprotective effects of VELCADE were investigated in two different models of focal cerebral ischemia. For time-window assessment, male Wistar-Kyoto rats were treated with 0.2 mg/kg VELCADE at 1, 2, or 3 h after the induction of permanent middle cerebral artery occlusion (MCAO) using the suture occlusion method (experiment 1). To evaluate effects in a different model, male Sprague-Dawley rats received 0.2 mg/kg VELCADE after embolic MCAO (experiment 2). Infarct volume was calculated based on TTC-staining 24 h postischemia and whole blood proteasome activity was fluorometrically determined in both experiments at baseline, 1 and 24 h post-MCAO. In experiment …


Laser Doppler Flowmetry Predicts Occlusion But Not Tpa-Mediated Reperfusion Success After Rat Embolic Stroke, Nils Henninger, James Bouley, Bernt Bratane, Birgül Bastan, Meghan Shea, Marc Fisher Apr 2015

Laser Doppler Flowmetry Predicts Occlusion But Not Tpa-Mediated Reperfusion Success After Rat Embolic Stroke, Nils Henninger, James Bouley, Bernt Bratane, Birgül Bastan, Meghan Shea, Marc Fisher

Nils Henninger

BACKGROUND AND PURPOSE: Laser Doppler flowmetry (LDF) is increasingly used to assess adequate occlusion after embolic stroke (ES) in rats. METHODS: Employing LDF, relative regional cerebral blood flow (rCBF) was continuously monitored during the first 2 h following ES and correlated with 24 h 2,3,5-triphenyltetrazolium chloride (TTC)-staining of corrected infarct volume. In a preliminary experiment (n=18), it was demonstrated that rCBF-reduction to 37% or less of baseline correctly identified occlusion success in the suture middle cerebral artery occlusion (sMCAO) model. Using the same methodology, we then assessed whether LDF allowed for identification of animals with successful ES (experiment 2, n=26) …


Visualization Of Clot Lysis In A Rat Embolic Stroke Model: Application To Comparative Lytic Efficacy, Ronn Walvick, Bernt Bratane, Nils Henninger, Kenneth Sicard, James Bouley, Zhanyang Yu, Eng Lo, Xiaoying Wang, Marc Fisher Apr 2015

Visualization Of Clot Lysis In A Rat Embolic Stroke Model: Application To Comparative Lytic Efficacy, Ronn Walvick, Bernt Bratane, Nils Henninger, Kenneth Sicard, James Bouley, Zhanyang Yu, Eng Lo, Xiaoying Wang, Marc Fisher

Nils Henninger

BACKGROUND AND PURPOSE: The purpose of this study was to develop a novel MRI method for imaging clot lysis in a rat embolic stroke model and to compare tissue plasminogen activator (tPA)-based clot lysis with and without recombinant Annexin-2 (rA2). METHODS: In experiment 1 we used in vitro optimization of clot visualization using multiple MRI contrast agents in concentrations ranging from 5 to 50 muL in 250 muL blood. In experiment 2, we used in vivo characterization of the time course of clot lysis using the clot developed in the previous experiment. Diffusion, perfusion, angiography, and T1-weighted MRI for clot …


Differences In Ischemic Lesion Evolution In Different Rat Strains Using Diffusion And Perfusion Imaging, Juergen Bardutzky, Qiang Shen, Nils Henninger, James Bouley, Timothy Duong, Marc Fisher Apr 2015

Differences In Ischemic Lesion Evolution In Different Rat Strains Using Diffusion And Perfusion Imaging, Juergen Bardutzky, Qiang Shen, Nils Henninger, James Bouley, Timothy Duong, Marc Fisher

Nils Henninger

BACKGROUND AND PURPOSE: Interstrain differences in the temporal evolution of ischemia after middle cerebral artery occlusion (MCAO) in rats may considerably influence the results of experimental stroke research. We investigated, in 2 commonly used rat strains (Sprague-Dawley [SD] and Wistar-Kyoto [WK]), the spatiotemporal evolution of ischemia after permanent suture MCAO using diffusion and perfusion imaging.

METHODS: Serial measurements of quantitative cerebral blood flow (CBF) and apparent diffusion coefficient (ADC) were performed up to 210 min after MCAO. Lesion volumes were calculated by using previously established viability thresholds and correlated with infarct volume defined by 2,3,5-triphenyltetrazolium chloride staining 24 hours after …


Differential Recovery Of Behavioral Status And Brain Function Assessed With Functional Magnetic Resonance Imaging After Mild Traumatic Brain Injury In The Rat, Nils Henninger, Kenneth Sicard, Zhixin Li, Praveen Kulkarni, Stephan Dutzmann, Christian Urbanek, Stefan Schwab, Marc Fisher Apr 2015

Differential Recovery Of Behavioral Status And Brain Function Assessed With Functional Magnetic Resonance Imaging After Mild Traumatic Brain Injury In The Rat, Nils Henninger, Kenneth Sicard, Zhixin Li, Praveen Kulkarni, Stephan Dutzmann, Christian Urbanek, Stefan Schwab, Marc Fisher

Nils Henninger

OBJECTIVE: The relationship between cerebral integrity, recovery of brain function, and neurologic status after mild traumatic brain injury is incompletely characterized.

DESIGN: Prospective and randomized study in rodents.

SETTING: University laboratory.

SUBJECTS: Male Wistar rats (290-310 g).

INTERVENTIONS: In rats, quantitative diffusion weighted imaging (DWI), perfusion weighted imaging (PWI), T2-weighted imaging (T2WI), and functional magnetic resonance imaging (fMRI) were performed up to 21 days after weight-induced, closed-head, mild traumatic brain injury (MTBI, n = 6) or sham operation (n = 6). Pixel-by-pixel analysis and region of interest analysis were used to evaluate structural (apparent diffusion coefficient [ADC] and basal cerebral …


Normobaric Hyperoxia And Delayed Tpa Treatment In A Rat Embolic Stroke Model, Nils Henninger, Bernt Bratane, Birgül Bastan, James Bouley, Marc Fisher Apr 2015

Normobaric Hyperoxia And Delayed Tpa Treatment In A Rat Embolic Stroke Model, Nils Henninger, Bernt Bratane, Birgül Bastan, James Bouley, Marc Fisher

Nils Henninger

In a rat embolic stroke (eMCAO) model, the effects of 100% normobaric hyperoxia (NBO) with delayed recombinant tissue plasminogen activator (tPA) administration on ischemic lesion size and safety were assessed by diffusion- and perfusion (PWI)-weighted magnetic resonance imaging. NBO or room air (Air) by a face mask was started at 30 mins posteMCAO and continued for 3.5 h. Tissue plasminogen activator or saline was started at 3 h posteMCAO. Types and location of hemorrhagic transformation were assessed at 24 h and a spectrophotometric hemoglobin assay quantified hemorrhage volume at 10 h. In NBO-treated animals the apparent diffusion coefficient/PWI mismatch persisted …


Acute Ischemic Stroke Therapy, Nils Henninger, Rajat Kumar, Marc Fisher Apr 2015

Acute Ischemic Stroke Therapy, Nils Henninger, Rajat Kumar, Marc Fisher

Nils Henninger

Data from the European Cooperative Acute Stroke Study (ECASS) III trial demonstrated that tissue plasminogen activator given up to 4.5 h after stroke onset improves outcome and treatment guidelines support its use during this time window. Intra-arterial therapy with tissue plasminogen activator or devices is commonly used at large tertiary centers up to 6-8 h after stroke onset, but conclusive evidence of efficacy remains lacking. During the acute phase after stroke onset, blood pressure elevations should be reduced as should substantial elevations in blood glucose. Statins are recommended in essentially all non-cardioembolic stroke patients. The most important future directions for …


Differential Recovery Of Multimodal Mri And Behavior After Transient Focal Cerebral Ischemia In Rats, Kenneth Sicard, Nils Henninger, Marc Fisher, Timothy Duong, Craig Ferris Apr 2015

Differential Recovery Of Multimodal Mri And Behavior After Transient Focal Cerebral Ischemia In Rats, Kenneth Sicard, Nils Henninger, Marc Fisher, Timothy Duong, Craig Ferris

Nils Henninger

The association between recovery of brain function and behavior after transient cerebral ischemia in animals and humans is incompletely characterized. Quantitative diffusion- (DWI), perfusion- (PWI), T(2)-weighted (T(2)WI), and functional magnetic resonance imaging (fMRI) were performed before, during, and up to 1 day after 20-mins transient middle cerebral artery occlusion (tMCAO; n=6) or sham operation (n=6) in male Sprague-Dawley rats. Viability thresholds were employed to calculate diffusion, perfusion, and T(2) lesion volumes. Region of interest analysis was used to evaluate structural and functional MR signal changes within the sensorimotor network, which were then related to corresponding behavioral measures. Post-mortem 2,3,5-triphenyltetrazolium chloride …