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Deficits In Retrospective And Prospective Components Underlying Prospective Memory Tasks In Amnestic Mild Cognitive Impairment, Ting Zhou, Lucas S. Broster, Yang Jiang, Feng Bao, Huali Wang, Juan Li Aug 2013

Deficits In Retrospective And Prospective Components Underlying Prospective Memory Tasks In Amnestic Mild Cognitive Impairment, Ting Zhou, Lucas S. Broster, Yang Jiang, Feng Bao, Huali Wang, Juan Li

Behavioral Science Faculty Publications

OBJECTIVES: By use of purer indices of PM and RM components than previous studies and adoption of three PM task types, the present study aimed to investigate the deficits of these two components underlying global impairment at a PM task in individuals with amnestic mild cognitive impairment (aMCI).

METHODS: Nineteen aMCI patients and 22 normal controls were examined on event-, time- and activity-based PM tasks. Separate scores were obtained for initiation of intentions (i.e. PM component) and for the content of the intentions (i.e. RM component).

RESULTS: Individuals with aMCI achieved lower PM component (but not RM component) scores than …


Autophagy Is Involved In Oligodendroglial Precursor-Mediated Clearance Of Amyloid Peptide, Wenxia Li, Yifen Tang, Zhiqin Fan, Ya Meng, Guang Yang, Jia Luo, Zun-Ji Ke Aug 2013

Autophagy Is Involved In Oligodendroglial Precursor-Mediated Clearance Of Amyloid Peptide, Wenxia Li, Yifen Tang, Zhiqin Fan, Ya Meng, Guang Yang, Jia Luo, Zun-Ji Ke

Internal Medicine Faculty Publications

BACKGROUND: Accumulation of β-amyloid peptides is an important hallmark of Alzheimer's disease (AD). Tremendous efforts have been directed to elucidate the mechanisms of β-amyloid peptides degradation and develop strategies to remove β-amyloid accumulation. In this study, we demonstrated that a subpopulation of oligodendroglial precursor cells, also called NG2 cells, were a new cell type that can clear β-amyloid peptides in the AD transgene mice and in NG2 cell line.

RESULTS: NG2 cells were recruited and clustered around the amyloid plaque in the APPswe/PS1dE9 mice, which is Alzheimer's disease mouse model. In vitro, NG2 cell line and primary NG2 cells engulfed …


A Multivariate Method To Determine The Dimensionality Of Neural Representation From Population Activity., Jörn Diedrichsen, Tobias Wiestler, Naveed Ejaz Aug 2013

A Multivariate Method To Determine The Dimensionality Of Neural Representation From Population Activity., Jörn Diedrichsen, Tobias Wiestler, Naveed Ejaz

Brain and Mind Institute Researchers' Publications

How do populations of neurons represent a variable of interest? The notion of feature spaces is a useful concept to approach this question: According to this model, the activation patterns across a neuronal population are composed of different pattern components. The strength of each of these components varies with one latent feature, which together are the dimensions along which the population represents the variable. Here we propose a new method to determine the number of feature dimensions that best describes the activation patterns. The method is based on Gaussian linear classifiers that use only the first d most important pattern …


Expression Of C-Fos In Hilar Mossy Cells Of The Dentate Gyrus In Vivo., Aine M Duffy, Michael J Schaner, Jeannie Chin, Helen E Scharfman Aug 2013

Expression Of C-Fos In Hilar Mossy Cells Of The Dentate Gyrus In Vivo., Aine M Duffy, Michael J Schaner, Jeannie Chin, Helen E Scharfman

Department of Neuroscience Faculty Papers

Granule cells (GCs) of the dentate gyrus (DG) are considered to be quiescent--they rarely fire action potentials. In contrast, the other glutamatergic cell type in the DG, hilar mossy cells (MCs) often have a high level of spontaneous activity based on recordings in hippocampal slices. MCs project to GCs, so activity in MCs could play an important role in activating GCs. Therefore, we investigated whether MCs were active under basal conditions in vivo, using the immediate early gene c-fos as a tool. We hypothesized that MCs would exhibit c-fos expression even if rats were examined randomly, under normal housing conditions. …


A Statement On Vemurafenib-Resistant Melanoma., Edward J Hartsough, A E Aplin Aug 2013

A Statement On Vemurafenib-Resistant Melanoma., Edward J Hartsough, A E Aplin

Department of Cancer Biology Faculty Papers

Despite recent advancements in the treatment of late-stage mutant BRAF (V600E/K) melanomas, a major hurdle continues to be acquired resistance to BRAF inhibitors such as vemurafenib. The mechanisms for resistance have proven to be heterogeneous, emphasizing the need to use broad therapeutic approaches. In this issue, the study "Stat3-targeted therapies overcome the acquired resistance to vemurafenib in melanomas" by Liu et al. proposes that signal transducer and activator of transcription 3 (STAT3)-paired box 3 (PAX3) signaling may be a mechanism that is used by melanomas to resist RAF inhibitors.


Hippocampal Functional Connectivity Patterns During Spatial Working Memory Differ In Right Versus Left Temporal Lobe Epilepsy., Gaelle Eve Doucet, Karol Osipowicz, Ashwini Sharan Md, Michael R Sperling, Joseph I Tracy Aug 2013

Hippocampal Functional Connectivity Patterns During Spatial Working Memory Differ In Right Versus Left Temporal Lobe Epilepsy., Gaelle Eve Doucet, Karol Osipowicz, Ashwini Sharan Md, Michael R Sperling, Joseph I Tracy

Department of Neurology Faculty Papers

Temporal lobe epilepsy (TLE), affecting the medial temporal lobe, is a disorder that affects not just episodic memory but also working memory (WM). However, the exact nature of hippocampal-related network activity in visuospatial WM remains unclear. To clarify this, we utilized a functional connectivity (FC) methodology to investigate hippocampal network involvement during the encoding phase of a functional magnetic resonance imaging (fMRI) visuospatial WM task in right and left TLE patients. Specifically, we assessed the relation between FC within right and left hippocampus-seeded networks, and patient performance (rate of correct responses) during the encoding phase of a block span WM …


Early Echocardiographic Changes After Percutaneous Implantation Of The Edwards Sapien Transcatheter Heart Valve In The Pulmonary Position., Shahryar M. Chowdhury, Ziyad M. Hijazi, John Rhodes, Saibal Kar, Raj Makkar, Michael Mullen, Qi-Ling Cao, Lydia King, Jodi Akin, Girish S. Shirali Aug 2013

Early Echocardiographic Changes After Percutaneous Implantation Of The Edwards Sapien Transcatheter Heart Valve In The Pulmonary Position., Shahryar M. Chowdhury, Ziyad M. Hijazi, John Rhodes, Saibal Kar, Raj Makkar, Michael Mullen, Qi-Ling Cao, Lydia King, Jodi Akin, Girish S. Shirali

Manuscripts, Articles, Book Chapters and Other Papers

OBJECTIVES: To evaluate echocardiographic changes after SAPIEN valve implantation in the pulmonary position.

BACKGROUND: The feasibility of the SAPIEN transcatheter pulmonary valve (TPV) has recently been demonstrated. We evaluated changes in pulmonary valve function and the right ventricle after SAPIEN TPV placement.

METHODS: We evaluated echocardiograms at baseline, discharge, 1 and 6 months after TPV placement in 33 patients from 4 centers. Pulmonary insufficiency severity was graded 0-4. TPV peak and mean gradients were measured. Right ventricular (RV) size and function were quantified using routine measures derived from color, spectral, and tissue Doppler indices and two-dimensional echocardiography.

RESULTS: At baseline, …


Prefrontal Cortical Microcircuits Bind Perception To Executive Control, Ioan Opris, Lucas Santos, Greg A. Gerhardt, Dong Song, Theodore W. Berger, Robert E. Hampson, Sam A. Deadwyler Jul 2013

Prefrontal Cortical Microcircuits Bind Perception To Executive Control, Ioan Opris, Lucas Santos, Greg A. Gerhardt, Dong Song, Theodore W. Berger, Robert E. Hampson, Sam A. Deadwyler

Neuroscience Faculty Publications

During the perception-to-action cycle, our cerebral cortex mediates the interactions between the environment and the perceptual-executive systems of the brain. At the top of the executive hierarchy, prefrontal cortical microcircuits are assumed to bind perceptual and executive control information to guide goal-driven behavior. Here, we tested this hypothesis by comparing simultaneously recorded neuron firing in prefrontal cortical layers and the caudate-putamen of rhesus monkeys, trained in a spatial-versus-object, rule-based match-to-sample task. We found that during the perception and executive selection phases, cell firing in the localized prefrontal layers and caudate-putamen region exhibited similar location preferences on spatial-trials, but less on …


An Integrated Clinico-Metabolomic Model Improves Prediction Of Death In Sepsis., Raymond J. Langley, Ephraim L. Tsalik, Jennifer C. Van Velkinburgh, Seth W. Glickman, Brandon J. Rice, Chunping Wang, Bo Chen, Lawrence Carin, Arturo Suarez, Robert P. Mohney, Debra H. Freeman, Mu Wang, Jinsam You, Jacob Wulff, J Will Thompson, M Arthur Moseley, Stephanie Reisinger, Brian T. Edmonds, Brian Grinnell, David R. Nelson, Darrell L. Dinwiddie, Neil A. Miller, Carol J. Saunders, Sarah Soden, Angela J. Rogers, Lee Gazourian, Laura E. Fredenburgh, Anthony F. Massaro, Rebecca M. Baron, Augustine M K Choi, G Ralph Corey, Geoffrey S. Ginsburg, Charles B. Cairns, Ronny M. Otero, Vance G. Fowler, Emanuel P. Rivers, Christopher W. Woods, Stephen F. Kingsmore Jul 2013

An Integrated Clinico-Metabolomic Model Improves Prediction Of Death In Sepsis., Raymond J. Langley, Ephraim L. Tsalik, Jennifer C. Van Velkinburgh, Seth W. Glickman, Brandon J. Rice, Chunping Wang, Bo Chen, Lawrence Carin, Arturo Suarez, Robert P. Mohney, Debra H. Freeman, Mu Wang, Jinsam You, Jacob Wulff, J Will Thompson, M Arthur Moseley, Stephanie Reisinger, Brian T. Edmonds, Brian Grinnell, David R. Nelson, Darrell L. Dinwiddie, Neil A. Miller, Carol J. Saunders, Sarah Soden, Angela J. Rogers, Lee Gazourian, Laura E. Fredenburgh, Anthony F. Massaro, Rebecca M. Baron, Augustine M K Choi, G Ralph Corey, Geoffrey S. Ginsburg, Charles B. Cairns, Ronny M. Otero, Vance G. Fowler, Emanuel P. Rivers, Christopher W. Woods, Stephen F. Kingsmore

Manuscripts, Articles, Book Chapters and Other Papers

Sepsis is a common cause of death, but outcomes in individual patients are difficult to predict. Elucidating the molecular processes that differ between sepsis patients who survive and those who die may permit more appropriate treatments to be deployed. We examined the clinical features and the plasma metabolome and proteome of patients with and without community-acquired sepsis, upon their arrival at hospital emergency departments and 24 hours later. The metabolomes and proteomes of patients at hospital admittance who would ultimately die differed markedly from those of patients who would survive. The different profiles of proteins and metabolites clustered into the …


Population Cancer Risks Associated With Coal Mining: A Systematic Review, Wiley D. Jenkins, W. Jay Christian, Georgia Mueller, K. Thomas Robbins Jul 2013

Population Cancer Risks Associated With Coal Mining: A Systematic Review, Wiley D. Jenkins, W. Jay Christian, Georgia Mueller, K. Thomas Robbins

Epidemiology and Environmental Health Faculty Publications

BACKGROUND: Coal is produced across 25 states and provides 42% of US energy. With production expected to increase 7.6% by 2035, proximate populations remain at risk of exposure to carcinogenic coal products such as silica dust and organic compounds. It is unclear if population exposure is associated with increased risk, or even which cancers have been studied in this regard.

METHODS: We performed a systematic review of English-language manuscripts published since 1980 to determine if coal mining exposure was associated with increased cancer risk (incidence and mortality).

RESULTS: Of 34 studies identified, 27 studied coal mining as an occupational exposure …


The Tumor Suppressor Tere1 (Ubiad1) Prenyltransferase Regulates The Elevated Cholesterol Phenotype In Castration Resistant Prostate Cancer By Controlling A Program Of Ligand Dependent Sxr Target Genes., William J. Fredericks, Jorge Sepulveda, Priti Lai, John E. Tomaszewski, Ming-Fong Lin, Terry Mcgarvey, Frank J. Rauscher, S. Bruce Malkowicz Jul 2013

The Tumor Suppressor Tere1 (Ubiad1) Prenyltransferase Regulates The Elevated Cholesterol Phenotype In Castration Resistant Prostate Cancer By Controlling A Program Of Ligand Dependent Sxr Target Genes., William J. Fredericks, Jorge Sepulveda, Priti Lai, John E. Tomaszewski, Ming-Fong Lin, Terry Mcgarvey, Frank J. Rauscher, S. Bruce Malkowicz

Journal Articles: Biochemistry & Molecular Biology

Castrate-Resistant Prostate Cancer (CRPC) is characterized by persistent androgen receptor-driven tumor growth in the apparent absence of systemic androgens. Current evidence suggests that CRPC cells can produce their own androgens from endogenous sterol precursors that act in an intracrine manner to stimulate tumor growth. The mechanisms by which CRPC cells become steroidogenic during tumor progression are not well defined. Herein we describe a novel link between the elevated cholesterol phenotype of CRPC and the TERE1 tumor suppressor protein, a prenyltransferase that synthesizes vitamin K-2, which is a potent endogenous ligand for the SXR nuclear hormone receptor. We show that 50% …


Progression Of Carotid Plaque Volume Predicts Cardiovascular Events, Thapat Wannarong, Grace Parraga, Daniel Buchanan, Aaron Fenster, Andrew A House, Daniel G Hackam, J David Spence Jul 2013

Progression Of Carotid Plaque Volume Predicts Cardiovascular Events, Thapat Wannarong, Grace Parraga, Daniel Buchanan, Aaron Fenster, Andrew A House, Daniel G Hackam, J David Spence

Medical Biophysics Publications

BACKGROUND AND PURPOSE: Carotid ultrasound evaluation of intima-media thickness (IMT) and plaque burden has been used for risk stratification and for evaluation of antiatherosclerotic therapies. Increasing evidence indicates that measuring plaque burden is superior to measuring IMT for both purposes. We compared progression/regression of IMT, total plaque area (TPA), and total plaque volume (TPV) as predictors of cardiovascular outcomes.

METHODS: IMT, TPA, and TPV were measured at baseline in 349 patients attending vascular prevention clinics; they had TPA of 40 to 600 mm(2) at baseline to qualify for enrollment. Participants were followed up for ≤5 years (median, 3.17 years) to …


Is Laparoscopy A Risk Factor For Bile Duct Injury During Cholecystectomy?, Terrence M. Fullum, Stephanie R. Downing, Gezzer Ortega, David C. Chang, Tolulope A. Oyetunji, Kendra Van Kirk, Daniel D. Tran, Ian Woods, Edward E. Cornwell, Patricia L. Turner Jul 2013

Is Laparoscopy A Risk Factor For Bile Duct Injury During Cholecystectomy?, Terrence M. Fullum, Stephanie R. Downing, Gezzer Ortega, David C. Chang, Tolulope A. Oyetunji, Kendra Van Kirk, Daniel D. Tran, Ian Woods, Edward E. Cornwell, Patricia L. Turner

Manuscripts, Articles, Book Chapters and Other Papers

BACKGROUND AND OBJECTIVES: Previously, risk factors for bile duct injury have been identified as acute cholecystitis, male gender, older age, aberrant biliary anatomy, and laparoscopic cholecystectomy.

METHODS: A retrospective analysis of the Nationwide Inpatient Sample from 1998 to 2006 was performed with an inclusion criterion of cholecystectomy performed on hospital day 0 or 1. Patient- and hospital-level factors potentially associated with bile duct injury were examined by logistic regression.

RESULTS: A total of 377,424 cholecystectomy patients were identified. There were 1124 bile duct injuries (0.30%), with 177 (0.06%) in the laparoscopic cholecystectomy group and 947 (1.46%) in the open cholecystectomy …


Support For A Smoke-Free Bylaw In Parks And On Beaches, Chizimuzo T.C. Okoli, Ann Pederson, Wendy Rice Jul 2013

Support For A Smoke-Free Bylaw In Parks And On Beaches, Chizimuzo T.C. Okoli, Ann Pederson, Wendy Rice

Nursing Faculty Publications

BACKGROUND: In September 2010, Vancouver, Canada enacted a smoke-free bylaw in parks and on beaches.

OBJECTIVE: To examine demographic and attitudinal factors associated with the public opinion on Vancouver's outdoor smoke-free bylaw.

METHODS: From 496 randomly selected Vancouver residents, information on demographics, smoking status, and opinions and support for or opposition to the smoke-free bylaw were obtained by telephone surveys.

RESULTS: Approximately 84.2% of the sample endorsed the legislation; a greater proportion of non-smokers supported the bylaw than smokers (88.6% vs. 52.0%). In multivariate analysis, demographic variables significantly associated with supporting the smoke-free bylaw were being female, having completed community …


Erps Reveal The Temporal Dynamics Of Auditory Word Recognition In Specific Language Impairment., Jeffrey G Malins, Amy S Desroches, Erin K Robertson, Randy Lynn Newman, Lisa M D Archibald, Marc F Joanisse Jul 2013

Erps Reveal The Temporal Dynamics Of Auditory Word Recognition In Specific Language Impairment., Jeffrey G Malins, Amy S Desroches, Erin K Robertson, Randy Lynn Newman, Lisa M D Archibald, Marc F Joanisse

Brain and Mind Institute Researchers' Publications

We used event-related potentials (ERPs) to compare auditory word recognition in children with specific language impairment (SLI group; N=14) to a group of typically developing children (TD group; N=14). Subjects were presented with pictures of items and heard auditory words that either matched or mismatched the pictures. Mismatches overlapped expected words in word-onset (cohort mismatches; see: DOLL, hear: dog), rhyme (CONE -bone), or were unrelated (SHELL -mug). In match trials, the SLI group showed a different pattern of N100 responses to auditory stimuli compared to the TD group, indicative of early auditory processing differences in SLI. However, the phonological mapping …


An Old Problem With A New Therapy: Gastrointestinal Bleeding In Ventricular Assist Device Patients And Deep Overtube-Assisted Enteroscopy., Konrad Sarosiek, Linda J Bogar, Mitchell I Conn, Brendan O'Hare, Hitoshi Hirose, Md, Phd, Nicholas C. Cavarocchi, Md Jul 2013

An Old Problem With A New Therapy: Gastrointestinal Bleeding In Ventricular Assist Device Patients And Deep Overtube-Assisted Enteroscopy., Konrad Sarosiek, Linda J Bogar, Mitchell I Conn, Brendan O'Hare, Hitoshi Hirose, Md, Phd, Nicholas C. Cavarocchi, Md

Department of Surgery Faculty Papers

Conventional algorithms for diagnosis and treatment of gastrointestinal bleeding (GIB) in patients with nonpulsatile ventricular assist devices (VADs) may take days to perform while patients require transfusions. We developed a new algorithm based on deep overtube-assisted enteroscopy (DOAE) to facilitate a rapid diagnosis and treatment. From 2004 to 2012, 84 patients who underwent VAD placement in our institution, were evaluated for episodes of GIB. Our new algorithm for the management of GIB using DOAE was evaluated by dividing the episodes into three groups: group A (traditional management without enteroscopy), group B (traditional management with enteroscopy performed >24 hours after presentation), …


Dna Methylation Analysis Reveals Distinct Methylation Signatures In Pediatric Germ Cell Tumors, James F. Amatruda, Julie A. Ross, Brock Christensen, Nicholas J. Fustino, Kenneth S. Chen, Anthony J. Hooten, Heather Nelson, Jacquelyn K. Kuriger, Dinesh Rakheja, A. Lindsay Frazier, Jenny N. Poynter Jun 2013

Dna Methylation Analysis Reveals Distinct Methylation Signatures In Pediatric Germ Cell Tumors, James F. Amatruda, Julie A. Ross, Brock Christensen, Nicholas J. Fustino, Kenneth S. Chen, Anthony J. Hooten, Heather Nelson, Jacquelyn K. Kuriger, Dinesh Rakheja, A. Lindsay Frazier, Jenny N. Poynter

Dartmouth Scholarship

Background: Aberrant DNA methylation is a prominent feature of many cancers, and may be especially relevant in germ cell tumors (GCTs) due to the extensive epigenetic reprogramming that occurs in the germ line during normal development. Methods: We used the Illumina GoldenGate Cancer Methylation Panel to compare DNA methylation in the three main histologic subtypes of pediatric GCTs (germinoma, teratoma and yolk sac tumor (YST); N = 51) and used recursively partitioned mixture models (RPMM) to test associations between methylation pattern and tumor and demographic characteristics. We identified genes and pathways that were differentially methylated using generalized linear models and …


Impaired Expression Of Protein Phosphatase 2a Subunits Enhances Metastatic Potential Of Human Prostate Cancer Cells Through Activation Of Akt Pathway., P Pandey, Parthasarathy Seshacharyulu, Srustidhar Das, Satyanarayana Rachagani, Moorthy P. Ponnusamy, Y Yan, Sonny L. Johansson, K Datta, Ming-Fong Lin, Surinder K. Batra Jun 2013

Impaired Expression Of Protein Phosphatase 2a Subunits Enhances Metastatic Potential Of Human Prostate Cancer Cells Through Activation Of Akt Pathway., P Pandey, Parthasarathy Seshacharyulu, Srustidhar Das, Satyanarayana Rachagani, Moorthy P. Ponnusamy, Y Yan, Sonny L. Johansson, K Datta, Ming-Fong Lin, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: Protein phosphatase 2A (PP2A) is a dephosphorylating enzyme, loss of which can contribute to prostate cancer (PCa) pathogenesis. The aim of this study was to analyse the transcriptional and translational expression patterns of individual subunits of the PP2A holoenzyme during PCa progression.

METHODS: Immunohistochemistry (IHC), western blot, and real-time PCR was performed on androgen-dependent (AD) and androgen-independent (AI) PCa cells, and benign and malignant prostate tissues for all the three PP2A (scaffold, regulatory, and catalytic) subunits. Mechanistic and functional studies were performed using various biochemical and cellular techniques.

RESULTS: Through immunohistochemical analysis we observed significantly reduced levels of PP2A-A …


Id4 Deficiency Attenuates Prostate Development And Promotes Pin-Like Lesions By Regulating Androgen Receptor Activity And Expression Of Nkx3.1 And Pten, Pankaj Sharma, Ashley Knowell, Swathi Chinaranagari, Shravan Komaragiri, Peri Nagappan, Divya Patel, Mathew C. Havrda, Jaideep Chaudhary Jun 2013

Id4 Deficiency Attenuates Prostate Development And Promotes Pin-Like Lesions By Regulating Androgen Receptor Activity And Expression Of Nkx3.1 And Pten, Pankaj Sharma, Ashley Knowell, Swathi Chinaranagari, Shravan Komaragiri, Peri Nagappan, Divya Patel, Mathew C. Havrda, Jaideep Chaudhary

Dartmouth Scholarship

Background: Inhibitor of differentiation 4 (Id4), a member of the helix-loop-helix family of transcriptional regulators has emerged as a tumor suppressor in prostate cancer. Id4 is expressed in the normal prostate where its expression is also regulated by androgens. In this study we investigated the effect of loss of Id4 (Id4-/-) on adult prostate morphology. Methods: Histological analysis was performed on prostates from 6-8 weeks old Id4-/-, Id4+/- and Id4+/+ mice. Expression of Id1, Sox9, Myc, androgen receptor, Akt, p-Akt, Pten and Nkx3.1 was investigated by immunohistochemistry. Androgen receptor binding on NKX3.1 promoter was studied by chromatin immuno-precipitation. Id4 was …


Dynamic And Opposing Adjustment Of Movement Cancellation And Generation In An Oculomotor Countermanding Task., Brian D Corneil, Joshua C Cheng, Samanthi C Goonetilleke Jun 2013

Dynamic And Opposing Adjustment Of Movement Cancellation And Generation In An Oculomotor Countermanding Task., Brian D Corneil, Joshua C Cheng, Samanthi C Goonetilleke

Brain and Mind Institute Researchers' Publications

Adaptive adjustments of strategies help optimize behavior in a dynamic and uncertain world. Previous studies in the countermanding (or stop-signal) paradigm have detailed how reaction times (RTs) change with trial sequence, demonstrating adaptive control of movement generation. Comparatively little is known about the adaptive control of movement cancellation in the countermanding task, mainly because movement cancellation implies the absence of an outcome and estimates of movement cancellation require hundreds of trials. Here, we exploit a within-trial proxy of movement cancellation based on recordings of neck muscle activity while human subjects attempted to cancel large eye-head gaze shifts. On a subset …


Intracranial Injection Of Gammagard, A Human Ivig, Modulates The Inflammatory Response Of The Brain And Lowers AΒ In App/Ps1 Mice Along A Different Time Course Than Anti-AΒ Antibodies, Tiffany L. Sudduth, Abigail Greenstein, Donna M. Wilcock Jun 2013

Intracranial Injection Of Gammagard, A Human Ivig, Modulates The Inflammatory Response Of The Brain And Lowers AΒ In App/Ps1 Mice Along A Different Time Course Than Anti-AΒ Antibodies, Tiffany L. Sudduth, Abigail Greenstein, Donna M. Wilcock

Sanders-Brown Center on Aging Faculty Publications

Gammagard IVIg is a therapeutic approach to treat Alzheimer's disease currently in phase 3 clinical trials. Despite the reported efficacy of the approach the mechanism of action is poorly understood. We have previously shown that intracranial injection of anti-Aβ antibodies into the frontal cortex and hippocampus reveals important information regarding the time course of events once the agent is in the brain. In the current study we compared IVIg, mouse-pooled IgG, and the anti-Aβ antibody 6E10 injected intracranially into the frontal cortex and hippocampus of 7-month-old APP/PS1 mice. We established a time course of events ranging from 1 …


B Cell Response And Hemagglutinin Stalk-Reactive Antibody Production In Different Age Cohorts Following 2009 H1n1 Influenza Virus Vaccination, Mark Y. Sangster, Jane Baer, Felix W. Santiago, Theresa T. Fitzgerald, Natalia A. Ilyushina Jun 2013

B Cell Response And Hemagglutinin Stalk-Reactive Antibody Production In Different Age Cohorts Following 2009 H1n1 Influenza Virus Vaccination, Mark Y. Sangster, Jane Baer, Felix W. Santiago, Theresa T. Fitzgerald, Natalia A. Ilyushina

Dartmouth Scholarship

The 2009 pandemic H1N1 (pH1N1) influenza virus carried a swine-origin hemagglutinin (HA) that was closely related to the HAs of pre-1947 H1N1 viruses but highly divergent from the HAs of recently circulating H1N1 strains. Consequently, prior ex- posure to pH1N1-like viruses was mostly limited to individuals over the age of about 60 years. We related age and associated dif- ferences in immune history to the B cell response to an inactivated monovalent pH1N1 vaccine given intramuscularly to subjects in three age cohorts: 18 to 32 years, 60 to 69 years, and >70 years. The day 0 pH1N1-specific hemagglutination inhibition (HAI) …


Two Distinct Ipsilateral Cortical Representations For Individuated Finger Movements., Jörn Diedrichsen, Tobias Wiestler, John W Krakauer Jun 2013

Two Distinct Ipsilateral Cortical Representations For Individuated Finger Movements., Jörn Diedrichsen, Tobias Wiestler, John W Krakauer

Brain and Mind Institute Researchers' Publications

Movements of the upper limb are controlled mostly through the contralateral hemisphere. Although overall activity changes in the ipsilateral motor cortex have been reported, their functional significance remains unclear. Using human functional imaging, we analyzed neural finger representations by studying differences in fine-grained activation patterns for single isometric finger presses. We demonstrate that cortical motor areas encode ipsilateral movements in 2 fundamentally different ways. During unimanual ipsilateral finger presses, primary sensory and motor cortices show, underneath global suppression, finger-specific activity patterns that are nearly identical to those elicited by contralateral mirror-symmetric action. This component vanishes when both motor cortices are …


Prevalence And Patterns Of Sexting Among Ethnic Minority Urban High School Students, Melissa Fleschler Peskin, Christine M Markham, Robert C Addy, Ross Shegog, Melanie Thiel, Susan R Tortolero Jun 2013

Prevalence And Patterns Of Sexting Among Ethnic Minority Urban High School Students, Melissa Fleschler Peskin, Christine M Markham, Robert C Addy, Ross Shegog, Melanie Thiel, Susan R Tortolero

Student and Faculty Publications

Although sexting among U.S. youth has received much popular media attention, there are only limited data on its prevalence among ethnic minority youth. This study, therefore, specifically examined the prevalence and patterns of sexting (sending and/or receiving a nude or semi-nude picture/video or a sexual text-only message) among a sample of black and Hispanic youth. Data from 1,034 tenth graders from a large, urban school district in southeast Texas were used to calculate the prevalence of sexting by gender-race/ethnicity. Overlap among sexting behaviors was also examined. Electronic surveys were administered via an audio-computer-assisted self-interview on laptop computers. Prevalence estimates were …


Prefrontal Neurons Of Opposite Spatial Preference Display Distinct Target Selection Dynamics., Therese Lennert, Julio C Martinez-Trujillo May 2013

Prefrontal Neurons Of Opposite Spatial Preference Display Distinct Target Selection Dynamics., Therese Lennert, Julio C Martinez-Trujillo

Brain and Mind Institute Researchers' Publications

Neurons in the primate dorsolateral prefrontal cortex (dlPFC) of one hemisphere are selective for the location of attended targets in both visual hemifields. Whether dlPFC neurons with selectivity for opposite hemifields directly compete with each other for target selection or instead play distinct roles during the allocation of attention remains unclear. We explored this issue by recording neuronal responses in the right dlPFC of two macaques while they allocated attention to a target in one hemifield and ignored a distracter on the opposite side. Forty-nine percent of the recorded neurons were target location selective. Neurons selective for contralateral targets (58%) …


Decoding The Neural Mechanisms Of Human Tool Use., Jason P Gallivan, D Adam Mclean, Kenneth F Valyear, Jody C Culham May 2013

Decoding The Neural Mechanisms Of Human Tool Use., Jason P Gallivan, D Adam Mclean, Kenneth F Valyear, Jody C Culham

Brain and Mind Institute Researchers' Publications

Sophisticated tool use is a defining characteristic of the primate species but how is it supported by the brain, particularly the human brain? Here we show, using functional MRI and pattern classification methods, that tool use is subserved by multiple distributed action-centred neural representations that are both shared with and distinct from those of the hand. In areas of frontoparietal cortex we found a common representation for planned hand- and tool-related actions. In contrast, in parietal and occipitotemporal regions implicated in hand actions and body perception we found that coding remained selectively linked to upcoming actions of the hand whereas …


Significant Sequelae After Bacterial Meningitis In Niger: A Cohort Study, Jean-François Jusot, Zilahatou Tohon, Abdoul Aziz Yazi, Jean-Marc Collard May 2013

Significant Sequelae After Bacterial Meningitis In Niger: A Cohort Study, Jean-François Jusot, Zilahatou Tohon, Abdoul Aziz Yazi, Jean-Marc Collard

Epidemiology and Environmental Health Faculty Publications

BACKGROUND: Beside high mortality, acute bacterial meningitis may lead to a high frequency of neuropsychological sequelae. The Sahelian countries belonging to the meningitis belt experience approximately 50% of the meningitis cases occurring in the world. Studies in Africa have shown that N. meningitidis could cause hearing loss in up to 30% of the cases, exceeding sometimes measles. The situation is similar in Niger which experiences yearly meningitis epidemics and where rehabilitation wards are rare and hearing aids remain unaffordable. The aim of this study was to estimate the frequency of neuropsychological sequelae after acute bacterial meningitis in four of the …


Pilot Comparative Effectiveness Study Of Surface Perturbation Treadmill Training To Prevent Falls In Older Adults, Jon D. Lurie, Alexandra B. Zagaria, Dawna M. Pidgeon, Judith L. Forman, Kevin Spratt May 2013

Pilot Comparative Effectiveness Study Of Surface Perturbation Treadmill Training To Prevent Falls In Older Adults, Jon D. Lurie, Alexandra B. Zagaria, Dawna M. Pidgeon, Judith L. Forman, Kevin Spratt

Dartmouth Scholarship

Falls are the leading cause of fatal and non-fatal injuries among older adults. Exercise programs appear to reduce fall risk, but the optimal type, frequency, and duration of exercise is unknown. External perturbations such as tripping and slipping are a major contributor to falls, and task-specific perturbation training to enhance dynamic stability has emerged as a promising approach to modifying fall risk. The purpose of this pilot study was 1) to determine the feasibility of conducting a large pragmatic randomized trial comparing a multidimensional exercise program inclusive of the surface perturbation treadmill training (SPTT) to multidimensional exercise alone (Standard PT); …


Maresin-1 Reduces The Pro-Inflammatory Response Of Bronchial Epithelial Cells To Organic Dust., Tara M. Nordgren, Art J. Heires, Todd A. Wyatt, Jill A. Poole, Tricia D. Levan, D. Roselyn Cerutis, Debra J. Romberger May 2013

Maresin-1 Reduces The Pro-Inflammatory Response Of Bronchial Epithelial Cells To Organic Dust., Tara M. Nordgren, Art J. Heires, Todd A. Wyatt, Jill A. Poole, Tricia D. Levan, D. Roselyn Cerutis, Debra J. Romberger

Journal Articles: Pulmonary & Critical Care Med

BACKGROUND: Exposure to organic dust causes detrimental airway inflammation. Current preventative and therapeutic measures do not adequately treat resulting disease, necessitating novel therapeutic interventions. Recently identified mediators derived from polyunsaturated fatty acids exhibit anti-inflammatory and pro-resolving actions. We tested the potential of one of these mediators, maresin-1 (MaR1), in reducing organic dust-associated airway inflammation.

METHODS: As bronchial epithelial cells (BECs) are pivotal in initiating organic dust-induced inflammation, we investigated the in vitro effects of MaR1 on a human BEC cell line (BEAS-2B). Cells were pretreated for 1 hour with 0-200 nM MaR1, followed by 1-24 hour treatment with 5% hog …


The Human Brain Processes Syntax In The Absence Of Conscious Awareness., Laura Batterink, Helen J Neville May 2013

The Human Brain Processes Syntax In The Absence Of Conscious Awareness., Laura Batterink, Helen J Neville

Brain and Mind Institute Researchers' Publications

Syntax is the core computational component of language. A longstanding idea about syntactic processing is that it is generally not available to conscious access, operating autonomously and automatically. However, there is little direct neurocognitive evidence on this issue. By measuring event-related potentials while human observers performed a novel cross-modal distraction task, we demonstrated that syntactic violations that were not consciously detected nonetheless produced a characteristic early neural response pattern, and also significantly delayed reaction times to a concurrent task. This early neural response was distinct from later neural activity that was observed only to syntactic violations that were consciously detected. …