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The Effects Of Lactation And Negative Energy Balance On Kisspeptin-Stimulated Luteinizing Hormone And Growth Hormone In Dairy Cows, Brian K. Whitlock, Joseph A. Daniel, Robyn R. Wilborn, Herris S. Maxwell, Barbara P. Steele, James L. Sartin Nov 2008

The Effects Of Lactation And Negative Energy Balance On Kisspeptin-Stimulated Luteinizing Hormone And Growth Hormone In Dairy Cows, Brian K. Whitlock, Joseph A. Daniel, Robyn R. Wilborn, Herris S. Maxwell, Barbara P. Steele, James L. Sartin

Brian K Whitlock, PhD, DVM, DACT

Kisspeptin, a neuroendocrine regulator of gonadotropin releasing hormone, is hypothesized to integrate nutrition and hormones critical to metabolism and the regulation of reproduction. Since the negative energy balance of early lactation is associated with reduced fertility via suppression of gonadotropin secretion and enhanced growth hormone (GH) responsiveness, this experiment was designed to determine the effects of stage of lactation and negative energy balance on kisspeptin-10 (Kp-10) stimulated luteinizing hormone (LH) and GH concentrations. Five nonlactating [5.1 ± 0.8 (SEM) years; 577 ± 19 kg body weight (BW)] and five lactating [4.1 ± 0.6 years; 608 ± 11 kg BW] multiparous …


Intrinsic Severity As A Determinant Of Antiepileptic Drug Refractoriness, Michael A. Rogawski, Michael R. Johnson Sep 2008

Intrinsic Severity As A Determinant Of Antiepileptic Drug Refractoriness, Michael A. Rogawski, Michael R. Johnson

Michael A. Rogawski

For the most part, resistance to medications in epilepsy is independent of the choice of antiepileptic drug. This simple clinical observation constrains the possible biological mechanisms for drug refractory epilepsy by imposing a requirement to explain resistance for a diverse set of chemical structures that act on an even more varied group of molecular targets. To date, research on antiepileptic drug refractoriness has been guided by the “drug transporter overexpression” and the “reduced drug-target sensitivity” hypotheses. These concepts posit that drug refractoriness is a condition separate from the underlying epilepsy. Inadequacies in both hypotheses mandate a fresh approach to the …


Impact Of Apoe Deficiency During Synaptic Remodeling In The Mouse Olfactory Bulb, Ikemefuna Nwosu, Salina Gairhe, Robert G. Struble, Britto P. Nathan Aug 2008

Impact Of Apoe Deficiency During Synaptic Remodeling In The Mouse Olfactory Bulb, Ikemefuna Nwosu, Salina Gairhe, Robert G. Struble, Britto P. Nathan

Britto P. Nathan

In this study we examined the role of apoE on the rate of synaptic recovery in the olfactory bulb (OB) following olfactory epithelium (OE) lesioning in mice. We used both immunoblotting and immunohistochemical techniques to compare the density of OB synaptophysin (Syn, a synaptic marker) in apoE-gene deficient/knockout (KO) mice and wild-type (WT) mice following OE lesion. We found that the whole bulb concentrations of Syn, measured by immunoblotting, declined sharply following injury in both WT and KO mice during the degenerative phase (3–7 days). After this initial decline, the Syn concentration gradually increased to normal levels by 56 days …


Simultaneous Confidence Bands For The Coefficient Function In Functional Regression, Philip T. Reiss Aug 2008

Simultaneous Confidence Bands For The Coefficient Function In Functional Regression, Philip T. Reiss

Philip T. Reiss

No abstract provided.


What Clinical Observations On The Epidemiology Of Antiepileptic Drug Intractability Tell Us About The Mechanisms Of Pharmacoresistance, Michael Rogawski Aug 2008

What Clinical Observations On The Epidemiology Of Antiepileptic Drug Intractability Tell Us About The Mechanisms Of Pharmacoresistance, Michael Rogawski

Michael A. Rogawski

In the past several years, there have been important advances in the clinical epidemiology of antiepileptic drug resistance, as reviewed by Mohanraj and Brodie. It would appear that by and large, intractability is independent of the choice of antiepileptic drug (AED). Many patients will become seizure free on the first agent tried, irrespective of which one their physician decides to pick. Nonresponders to the first drug are in a different category: it is likely that they will continue to have seizures no matter which medicine or combination of medicines is tried. This simple clinical observation puts important constraints on the …


Inferring Group Differences In Brain Connectivity From Functional Magnetic Resonance Images, Philip T. Reiss Jul 2008

Inferring Group Differences In Brain Connectivity From Functional Magnetic Resonance Images, Philip T. Reiss

Philip T. Reiss

No abstract provided.


Reliability Of Functional Connectivity Networks: How Can We Assess It?, Philip T. Reiss Jul 2008

Reliability Of Functional Connectivity Networks: How Can We Assess It?, Philip T. Reiss

Philip T. Reiss

No abstract provided.


Antiepileptic Drugs And Migraine, Michael Rogawski Apr 2008

Antiepileptic Drugs And Migraine, Michael Rogawski

Michael A. Rogawski

Prepared for the 16th International Headache Research Seminar, “Innovative Drug Development For Headache Disorders,” March 23–25, 2007, Copenhagen, Denmark.


Neurosciences And Education: One Example Of A Two-Way Cooperation, Armando F. Rocha, Fábio T. Rocha Jan 2008

Neurosciences And Education: One Example Of A Two-Way Cooperation, Armando F. Rocha, Fábio T. Rocha

Armando F Rocha

The relationship between education and cognitive neuroscience is an old issue from which the idea of the ‘neuroeducators’ was proposed 25 years ago. The premise of this idea is that the knowledge about how the brain operates our learning could help teachers in the classrootm. Despite of being an old issue, there are yet some unsolved matters. Firstly, how neuroscience and education could integrate biological understanding about learning cerebral process has not been yet clearly discussed. The present paper presents the results from Enscer– Teaching the Brain Project – that has been developed in Brazil for five years. During that …


Brivaracetam: A Rational Drug Discovery Success Story, Michael Rogawski Jan 2008

Brivaracetam: A Rational Drug Discovery Success Story, Michael Rogawski

Michael A. Rogawski

Levetiracetam, the alpha-ethyl analogue of the nootropic piracetam, is a widely used antiepileptic drug (AED) that provides protection against partial seizures and is also effective in the treatment of primary generalized seizure syndromes including juvenile myoclonic epilepsy. Levetiracetam was discovered in 1992 through screening in audiogenic seizure susceptible mice and, 3 years later, was reported to exhibit saturable, stereospecific binding in brain to a approximately 90 kDa protein, later identified as the ubiquitous synaptic vesicle glycoprotein SV2A. A large-scale screening effort to optimize binding affinity identified the 4-n-propyl analogue, brivaracetam, as having greater potency and a broadened spectrum of activity …


New Molecular Targets For Antiepileptic Drugs: Alpha2delta, Sv2a, And Kv7/Kcnq/M Potassium Channels, Michael A. Rogawski, Carl W. Bazil Jan 2008

New Molecular Targets For Antiepileptic Drugs: Alpha2delta, Sv2a, And Kv7/Kcnq/M Potassium Channels, Michael A. Rogawski, Carl W. Bazil

Michael A. Rogawski

Many currently prescribed antiepileptic drugs (AEDs) act via voltage-gated sodium channels, through effects on gamma-aminobutyric acid-mediated inhibition, or via voltage-gated calcium channels. Some newer AEDs do not act via these traditional mechanisms. The molecular targets for several of these nontraditional AEDs have been defined using cellular electrophysiology and molecular approaches. Here, we describe three of these targets: alpha(2)delta, auxiliary subunits of voltage-gated calcium channels through which the gabapentinoids gabapentin and pregabalin exert their anticonvulsant and analgesic actions; SV2A, a ubiquitous synaptic vesicle glycoprotein that may prepare vesicles for fusion and serves as the target for levetiracetam and its analog brivaracetam …


Constructive Perception Of Self-Motion, Jan E. Holly, Gin Mccollum Jan 2008

Constructive Perception Of Self-Motion, Jan E. Holly, Gin Mccollum

Gin McCollum

This review focusses attention on a ragged edge of our knowledge of self-motion perception, where understanding ends but there are experimental results to indicate that present approaches to analysis are inadequate. Although self-motion perception displays processes of “top-down” construction, it is typically analyzed as if it is nothing more than a deformation of the stimulus, using a “bottom-up” and input/output approach beginning with the transduction of the stimulus. Analysis often focusses on the extent to which passive transduction of the movement stimulus is accurate. Some perceptual processes that deform or transform the stimulus arise from the way known properties of …


Crf1 Receptor Antagonists Attenuate Escalated Cocaine Self-Administration In Rats, Laura O'Dell Jan 2008

Crf1 Receptor Antagonists Attenuate Escalated Cocaine Self-Administration In Rats, Laura O'Dell

Laura Elena O'Dell

No abstract provided.


Cellular And Behavioral Interactions Of Gabapentin With Alcohol Dependence, Laura O'Dell Jan 2008

Cellular And Behavioral Interactions Of Gabapentin With Alcohol Dependence, Laura O'Dell

Laura Elena O'Dell

No abstract provided.


Enhanced Vulnerability To The Rewarding Effects Of Nicotine During The Adolescent Period Of Development, Laura O'Dell Jan 2008

Enhanced Vulnerability To The Rewarding Effects Of Nicotine During The Adolescent Period Of Development, Laura O'Dell

Laura Elena O'Dell

No abstract provided.


Brain Bases Of Individual Differences In Cognition, Chantel Prat, Marcel Just Dec 2007

Brain Bases Of Individual Differences In Cognition, Chantel Prat, Marcel Just

Marcel Adam Just

No abstract provided.


A Decrease In Brain Activation Associated With Driving When Listening To Someone Speak, Marcel Just, Timothy Keller, Jacquelyn Cynkar Dec 2007

A Decrease In Brain Activation Associated With Driving When Listening To Someone Speak, Marcel Just, Timothy Keller, Jacquelyn Cynkar

Marcel Adam Just

No abstract provided.


Autism-Like Behavioral Phenotypes In Btbr Ttf/J Mice. Genes, Hewlet Mcfarlane Dec 2007

Autism-Like Behavioral Phenotypes In Btbr Ttf/J Mice. Genes, Hewlet Mcfarlane

Hewlet McFarlane

No abstract provided.


Fmri Investigation Of Working Memory For Faces In Autism: Visual Coding And Underconnectivity With Frontal Areas, Hideya Koshino, Rajesh Kana, Timothy Keller, Vladimir Cherkassky, Nancy Minshew, Marcel Just Dec 2007

Fmri Investigation Of Working Memory For Faces In Autism: Visual Coding And Underconnectivity With Frontal Areas, Hideya Koshino, Rajesh Kana, Timothy Keller, Vladimir Cherkassky, Nancy Minshew, Marcel Just

Marcel Adam Just

No abstract provided.


The Effects Of Prenatal Stress On Motivation In The Rat Pup, Howard Cromwell Dec 2007

The Effects Of Prenatal Stress On Motivation In The Rat Pup, Howard Cromwell

Howard Casey Cromwell

Exposure to prenatal stress (PNS) has been shown to induce a set of psychological and behavioral changes in developing offspring. We used the rodent model to investigate whether PNS produces changes in the ability of the pup to express social motivation.We used a set of behavioral tasks including monitoring ultrasonic vocalizations after isolation, a conditioned place preference, and a novel and familiar odor approach test. Pregnant Long–Evans rats were exposed to an unpredictable, variable stressor twice daily during the third week of gestation. Isolation vocalizations were assessed on postnatal day (PND) 10. Pup affinity for the dam was evaluated on …


Understanding Evaluation Of Faces On Social Dimensions., Alex Todorov, Said Chris, Andrew Engell, Nicholas Oosterhof Dec 2007

Understanding Evaluation Of Faces On Social Dimensions., Alex Todorov, Said Chris, Andrew Engell, Nicholas Oosterhof

Andrew Engell

n/a


Using Fmri Brain Activation To Identify Cognitive States Associated With Perception Of Tools And Dwellings, Svetlana V. Shinkareva, Robert A. Mason, Vicente L. Malave, Wei Wang, Tom M. Mitchell, Marcel Adam Just Dec 2007

Using Fmri Brain Activation To Identify Cognitive States Associated With Perception Of Tools And Dwellings, Svetlana V. Shinkareva, Robert A. Mason, Vicente L. Malave, Wei Wang, Tom M. Mitchell, Marcel Adam Just

Marcel Adam Just

No abstract provided.


Modifying The Brain Activation Of Poor Readers During Sentence Comprehension With Extended Remedial Instruction: A Longitudinal Study Of Neuroplasticity, Ann Meyler, Timothy A. Keller, Vladimir L. Cherkassky, John D. E. Gabrieli, Marcel Adam Just Dec 2007

Modifying The Brain Activation Of Poor Readers During Sentence Comprehension With Extended Remedial Instruction: A Longitudinal Study Of Neuroplasticity, Ann Meyler, Timothy A. Keller, Vladimir L. Cherkassky, John D. E. Gabrieli, Marcel Adam Just

Marcel Adam Just

No abstract provided.


Cellular Effects Of Antiepileptic Drugs, Robert L. Macdonald, Michael A. Rogawski Dec 2007

Cellular Effects Of Antiepileptic Drugs, Robert L. Macdonald, Michael A. Rogawski

Michael A. Rogawski

Antiepileptic drugs (AEDs) protect against seizures through interactions with a variety of cellular targets, which include various ion channels, a neurotransmitter transporter, a neurotransmitter metabolic enzyme, and a synaptic vesicle protein. AED actions on these targets can be categorized into four broad groups: 1. Modulation of voltage-dependent ion channels (mainly sodium [Na] but also calcium [Ca] channels) 2. Effects on γ-aminobutyric acid (GABA) systems, including alterations in the cellular disposition of GABA and enhancement of synaptic inhibition mediated by GABA-A receptors 3. Inhibition of synaptic excitation mediated by ionotropic glutamate receptors 4. Modulation of neurotransmitter release, particularly of glutamate, through …


What Brain Imaging Can Tell Us About Embodied Meaning, Marcel Adam Just Dec 2007

What Brain Imaging Can Tell Us About Embodied Meaning, Marcel Adam Just

Marcel Adam Just

No abstract provided.


Theory Of Mind Disruption And Recruitment Of The Right Hemisphere During Narrative Comprehension In Autism, Robert A. Mason, Diane L. Williams, Rajesh K. Kana, Nancy J. Minshew, Marcel Adam Just Dec 2007

Theory Of Mind Disruption And Recruitment Of The Right Hemisphere During Narrative Comprehension In Autism, Robert A. Mason, Diane L. Williams, Rajesh K. Kana, Nancy J. Minshew, Marcel Adam Just

Marcel Adam Just

No abstract provided.


Common Pathophysiologic Mechanisms In Migraine And Epilepsy, Michael A. Rogawski Dec 2007

Common Pathophysiologic Mechanisms In Migraine And Epilepsy, Michael A. Rogawski

Michael A. Rogawski

Migraine and epilepsy are comorbid episodic disorders that have common pathophysiologic mechanisms. Migraine attacks, like epileptic seizures, may be triggered by excessive neocortical cellular excitability; in migraine, however, the hyperexcitability is believed to transition to cortical spreading depression rather than to the hypersynchronous activity that characterizes seizures. Some forms of epilepsy and migraine are known to be channelopathies. Mutations in the same genes can cause either migraine or epilepsy or, in some cases, both. Given the likely commonalities in the underlying cellular and molecular mechanisms, it is not surprising that some antiepileptic drugs, including valproate, topiramate, and gabapentin, are effective …


Predicting Human Brain Activity Associated With The Meanings Of Nouns, Tom M. Mitchell, Svetlana V. Shinkareva, Andrew Carlson, Kai-Min Chang, Vicente L. Malave, Robert A. Mason, Marcel Adam Just Dec 2007

Predicting Human Brain Activity Associated With The Meanings Of Nouns, Tom M. Mitchell, Svetlana V. Shinkareva, Andrew Carlson, Kai-Min Chang, Vicente L. Malave, Robert A. Mason, Marcel Adam Just

Marcel Adam Just

No abstract provided.


Functional Generalized Linear Models With Applications To Neuroimaging, Philip T. Reiss, R. Todd Ogden Dec 2007

Functional Generalized Linear Models With Applications To Neuroimaging, Philip T. Reiss, R. Todd Ogden

Philip T. Reiss

No abstract provided.


The Role Of The Amygdala In Implicit Evaluation Of Emotionally Neutral Faces., Alex Todorov, Andrew D. Engell Dec 2007

The Role Of The Amygdala In Implicit Evaluation Of Emotionally Neutral Faces., Alex Todorov, Andrew D. Engell

Andrew D. Engell

The amygdala is involved in the evaluation of novel stimuli, including faces. We examined whether the amygdala is engaged during the evaluation of emotionally neutral faces along trait-specific dimensions such as trustworthiness and attractiveness or along a general valence dimension. Using behavioral data from evaluation of faces on 14 trait dimensions and fMRI data from an implicit evaluation paradigm, we show that the extent to which the amygdala responds to variations of faces on specific dimensions is a function of the valence content of these dimensions. Variations on dimensions with clear valence connotations (e.g. trustworthiness) engaged the amygdala more strongly …