33 results on '"Erin Flaherty"'
Search Results
2. Transcriptional signatures of schizophrenia in hiPSC-derived NPCs and neurons are concordant with post-mortem adult brains
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Gabriel E. Hoffman, Brigham J. Hartley, Erin Flaherty, Ian Ladran, Peter Gochman, Douglas M. Ruderfer, Eli A. Stahl, Judith Rapoport, Pamela Sklar, and Kristen J. Brennand
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Science - Abstract
Induced pluripotent stem cell (hiPSC)-based models have inherent variations in their cellular and molecular output and readouts. Here, Hoffman and colleagues devise a method to account for gene expression variations in hiPSC-derived neurons from patients with childhood-onset schizophrenia.
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- 2017
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3. Evaluating Synthetic Activation and Repression of Neuropsychiatric-Related Genes in hiPSC-Derived NPCs, Neurons, and Astrocytes
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Seok-Man Ho, Brigham J. Hartley, Erin Flaherty, Prashanth Rajarajan, Rawan Abdelaal, Ifeanyi Obiorah, Natalie Barretto, Hamza Muhammad, Hemali P. Phatnani, Schahram Akbarian, and Kristen J. Brennand
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Medicine (General) ,R5-920 ,Biology (General) ,QH301-705.5 - Abstract
Summary: Modulation of transcription, either synthetic activation or repression, via dCas9-fusion proteins is a relatively new methodology with the potential to facilitate high-throughput up- or downregulation studies of gene function. Genetic studies of neurodevelopmental disorders have identified a growing list of risk variants, including both common single-nucleotide variants and rare copy-number variations, many of which are associated with genes having limited functional annotations. By applying a CRISPR-mediated gene-activation/repression platform to populations of human-induced pluripotent stem cell-derived neural progenitor cells, neurons, and astrocytes, we demonstrate that it is possible to manipulate endogenous expression levels of candidate neuropsychiatric risk genes across these three cell types. Although proof-of-concept studies using catalytically inactive Cas9-fusion proteins to modulate transcription have been reported, here we present a detailed survey of the reproducibility of gRNA positional effects across a variety of neurodevelopmental disorder-relevant risk genes, donors, neural cell types, and dCas9 effectors. : Brennand and colleagues report a survey of the reproducibility of CRISPR-mediated transcriptional modulation across varied neurodevelopmental disorder risk genes, donors, neural cell types, and dCas9 effectors. We report a number of practical limitations that must be considered when designing hiPSC-based studies using this promising new tool. Keywords: CRISPR, human-induced pluripotent stem cell, neural progenitor cell, transcriptional modulation, dCas9-VP64, dCas9-VPR, dCas9-KRAB
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- 2017
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4. Massive exophytic malignant peripheral nerve sheath tumor
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Derek Khorsand, MD, Jack Porrino, MD, Erin Flaherty, MD, Anshu Bandhlish, MD, and Darin Davidson, MD
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Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
We present a case of a solitary neurofibroma involving the right posterior shoulder of a 69-year-old man with degeneration into a massive, malignant peripheral nerve sheath tumor measuring more than 3 times the average reported size. The radiographic, magnetic resonance imaging, and computed tomographic features are compared with the gross appearance and pathology.
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- 2016
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5. Predicting outcomes from sentinel node biopsy for melanoma in the UK: Is the MIA nomogram the answer?
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Miss Abbie Carter, Miss Erin Flaherty, Miss Sarah Hemington-Gorse, and Mr Jonathan J. Cubitt
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Nomograms ,Skin Neoplasms ,Sentinel Lymph Node Biopsy ,Humans ,Lymph Node Excision ,Surgery ,Lymph Nodes ,Melanoma ,United Kingdom - Published
- 2022
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6. The role of clustered protocadherins in neurodevelopment and neuropsychiatric diseases
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Tom Maniatis and Erin Flaherty
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Gene isoform ,Cell type ,Transcription, Genetic ,Neurite ,Locus (genetics) ,Biology ,Article ,03 medical and health sciences ,0302 clinical medicine ,Genetics ,medicine ,Animals ,Humans ,Protein Isoforms ,Gene ,030304 developmental biology ,0303 health sciences ,Mental Disorders ,Cadherins ,medicine.disease ,medicine.anatomical_structure ,Gene Expression Regulation ,Neurodevelopmental Disorders ,Autism ,Human genome ,Neuron ,Neuroscience ,030217 neurology & neurosurgery ,Developmental Biology - Abstract
During development, individual neurons extend highly branched arbors that innervate the surrounding territory, enabling the formation of appropriate synaptic connections. The clustered protocadherins (cPCDH), a family of diverse cell-surface homophilic proteins, provide each neuron with a cell specific identity required for distinguishing between self versus non-self. While only 52 unique cPcdh isoforms are encoded in the human genome, a combination of stochastic promoter choice and the formation of a protein lattice through engagement of adjacent cPCDH protein cis/trans-tetramers confer the high degree of cellular specificity required for self-recognition. Studies of mice bearing deletions of individual cPcdh gene clustees have identified deficits in circuit formation and behavior. In humans, single nucleotide variants scattered across the cPCDH locus have been identified, which associate with multiple neurodevelopmental disorders, including autism and schizophrenia. To advance our understanding of cPCDH stochastic choice and maintenance, function across cell types, and contribution to neuropsychiatric disease pathogenesis, hiPSC-based models have been developed. Ultimately, integration of human genetic data, biochemical assays, and functional studies is needed to uncover the mechanism underlying neurite repulsion, which has been implicated in neurodevelopmental disorders.
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- 2020
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7. CRISPR-based functional evaluation of schizophrenia risk variants
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Schahram Akbarian, Erin Flaherty, Prashanth Rajarajan, and Kristen J. Brennand
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Treatment response ,Functional evaluation ,Genome ,Schizophrenia (object-oriented programming) ,Induced Pluripotent Stem Cells ,Brain ,Computational biology ,Biology ,Article ,030227 psychiatry ,Genome engineering ,03 medical and health sciences ,Psychiatry and Mental health ,0302 clinical medicine ,Genotype ,Schizophrenia ,Humans ,CRISPR ,Clustered Regularly Interspaced Short Palindromic Repeats ,Induced pluripotent stem cell ,030217 neurology & neurosurgery ,Biological Psychiatry ,Psychiatric genetics - Abstract
As expanding genetic and genomic studies continue to implicate a growing list of variants contributing risk to neuropsychiatric disease, an important next step is to understand the functional impact and points of convergence of these risk factors. Here, with a focus on schizophrenia, we survey the most recent findings of the rare and common variants underlying genetic risk for schizophrenia. We discuss the ongoing efforts to validate these variants in post-mortem brain tissue, as well as new approaches to combine CRISPR-based genome engineering with patient-specific human induced pluripotent stem cell (hiPSC)-based models, in order to identify putative causal schizophrenia loci that regulate gene expression and cellular function. We consider the current limitations of hiPSC-based approaches as well as the future advances necessary to improve the fidelity of this human model. With the objective of utilizing patient genotype data to improve diagnosis and predict treatment response, the integration of CRISPR-genome engineering and hiPSC-based models represent an important strategy with which to systematically demonstrate the cell-type-specific effects of schizophrenia-associated variants.
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- 2020
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8. Synergistic effects of common schizophrenia risk variants
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Esther Cheng, Erin Flaherty, Gabriel E. Hoffman, Marliette R. Matos, Amanda Dobbyn, Vineeta Singh, Deeptha Girish, Eli A. Stahl, Hirofumi Morishita, Laura M. Huckins, Seok-Man Ho, Emily Hoelzli, Sonya Abadali, Robert E. McCullumsmith, Pamela Sklar, Kazuhiko Yamamuro, Aaron Topol, Hemali Phatnani, Khaled Alganem, P J Michael Deans, Nadine Schrode, Bruce J. Aronow, James Gardner Gregory, Natalie Barretto, and Kristen J. Brennand
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Male ,Induced Pluripotent Stem Cells ,Quantitative Trait Loci ,Genome-wide association study ,Computational biology ,Quantitative trait locus ,Polymorphism, Single Nucleotide ,Article ,03 medical and health sciences ,0302 clinical medicine ,Genome editing ,Chloride Channels ,Gene expression ,Genetics ,Humans ,Genetic Predisposition to Disease ,Furin ,Gene ,030304 developmental biology ,Regulation of gene expression ,Gene Editing ,0303 health sciences ,Binding Sites ,biology ,Gene Expression Regulation ,Monomeric Clathrin Assembly Proteins ,Expression quantitative trait loci ,biology.protein ,Schizophrenia ,Female ,CRISPR-Cas Systems ,SNARE Proteins ,030217 neurology & neurosurgery ,Genome-Wide Association Study - Abstract
The mechanisms by which common risk variants of small effect interact to contribute to complex genetic disorders remain unclear. Here, we apply a genetic approach, using isogenic human induced pluripotent stem cells (hiPSCs), to evaluate the effects of schizophrenia-associated common variants predicted to function as brain expression quantitative trait loci (SZ-eQTLs). By integrating CRISPR-mediated gene editing, activation and repression technologies to study one putative SZ-eQTL (FURIN rs4702) and four top-ranked SZ-eQTL genes (FURIN, SNAP91, TSNARE1, CLCN3), our platform resolves pre- and post-synaptic neuronal deficits, recapitulates genotype-dependent gene expression differences, and identifies convergence downstream of SZ-eQTL gene perturbations. Our observations highlight the cell-type-specific effects of common variants and demonstrate a synergistic effect between SZ-eQTL genes that converges on synaptic function. We propose that the links between rare and common variants implicated in psychiatric disease risk constitute a potentially generalizable phenomenon occurring more widely in complex genetic disorders.
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- 2019
9. Novel Ultra-Rare Exonic Variants Identified in a Founder Population Implicate Cadherins in Schizophrenia
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Lorraine N. Clark, Tom Maniatis, Harry Ostrer, Raiyan R. Khan, Nir Barzilai, Shai Carmi, Joseph Vijai, Laurie J. Ozelius, Max Lam, Danny Ben-Avraham, Susan B. Bressman, Anil K. Malhotra, Judy H. Cho, Ariel Darvasi, Erin Flaherty, Kenneth Offit, Steven M. Lipkin, Jin Yu, Robert J. Klein, Todd Lencz, Itsik Pe'er, Zeynep H. Gümüş, Gil Atzmon, and Inga Peter
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0301 basic medicine ,Male ,Population ,Protocadherin ,Genome-wide association study ,Biology ,03 medical and health sciences ,Negative selection ,0302 clinical medicine ,medicine ,Humans ,Missense mutation ,Genetic Predisposition to Disease ,education ,Gene ,Loss function ,Genetic association ,Genetics ,education.field_of_study ,Genetic heterogeneity ,General Neuroscience ,Exons ,Cadherins ,medicine.disease ,Founder Effect ,030104 developmental biology ,Schizophrenia ,Jews ,Mutation ,Female ,030217 neurology & neurosurgery ,Founder effect - Abstract
IMPORTANCE Schizophrenia is a serious mental illness with high heritability. While common genetic variants account for a portion of the heritability, identification of rare variants associated with the disorder has proven challenging. OBJECTIVE To identify genes and gene sets associated with schizophrenia in a founder population (Ashkenazi Jewish), and to determine the relative power of this population for rare variant discovery. DESIGN, SETTING, AND PARTICIPANTS Data on exonic variants were extracted from whole genome sequences drawn from 786 patients with schizophrenia and 463 healthy control subjects, all drawn from the Ashkenazi Jewish population. Variants observed in two large publicly available datasets (total n≈153,000, excluding neuropsychiatric patients) were filtered out, and novel ultra-rare variants (URVs) were compared in cases and controls. MAIN OUTCOMES AND MEASURES The number of novel URVs and genes carrying them were compared across cases and controls. Genes in which only cases or only controls carried novel, functional URVs were examined using gene set analyses. RESULTS Cases had a higher frequency of novel missense or loss of function (MisLoF) variants compared to controls, as well as a greater number of genes impacted by MisLoF variants. Characterizing 141 “case-only” genes (in which ≥ 3 AJ cases in our dataset had MisLoF URVs with none found in our AJ controls), we replicated prior findings of both enrichment for synaptic gene sets, as well as specific genes such as SETD1A and TRIO. Additionally, we identified cadherins as a novel gene set associated with schizophrenia including a recurrent mutation in PCDHA3. Several genes associated with autism and other neurodevelopmental disorders including CACNA1E, ASXL3, SETBP1, and WDFY3, were also identified in our case-only gene list, as was TSC2, which is linked to tuberous sclerosis. Modeling the effects of purifying selection demonstrated that deleterious rare variants are greatly over-represented in a founder population with a tight bottleneck and rapidly expanding census, resulting in enhanced power for rare variant association studies. CONCLUSIONS AND RELEVANCE Identification of cell adhesion genes in the cadherin/protocadherin family is consistent with evidence from large-scale GWAS in schizophrenia, helps specify the synaptic abnormalities that may be central to the disorder, and suggests novel potential treatment strategies (e.g., inhibition of protein kinase C). Study of founder populations may serve as a cost-effective way to rapidly increase gene discovery in schizophrenia and other complex disorders.
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- 2020
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10. A Systematic Review of Culturally Specific Interventions to Increase Physical Activity for Older Asian Americans
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Tam Nguyen, Ying-Yu Chao, Daphne Sze Ki Cheung, Erin Flaherty, Rick Yiu Cho Kwan, and Carina Katigbak
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Advanced and Specialized Nursing ,Gerontology ,Asian ,business.industry ,Health Behavior ,Ethnic group ,Psychological intervention ,Health Promotion ,Disease ,030204 cardiovascular system & hematology ,03 medical and health sciences ,0302 clinical medicine ,Quality of life (healthcare) ,Intervention (counseling) ,Humans ,Medicine ,030212 general & internal medicine ,Data reporting ,Risk factor ,Cardiology and Cardiovascular Medicine ,business ,Exercise ,Chinese americans - Abstract
Background Physical activity (PA) is a significant modifiable risk factor for cardiovascular disease. For older adults, engaging in PA is shown to improve cardiac status, reduce cognitive, and functional decline, and improve overall quality of life. However, only 17% of Asian American adults meet the 2008 federal recommended guidelines for aerobic and muscle strengthening activity; and there is a paucity of data reporting on older Asian Americans - a rapidly growing, underserved group. While data pertaining to Asian Americans is frequently reported at the aggregate level, this masks differences (eg, language, culture, income) among Asian ethnic subgroups that may impact health behaviors. The purpose of this review was to identify intervention, and cultural adaptation strategies in studies promoting PA for older Asian Americans. Methods A comprehensive literature search was performed to identify interventions published between 1996-2016 focused on improving PA among older Asian Americans (> 60 years old). Data were abstracted to examine intervention study designs, cultural adaptation strategies, theoretical frameworks, and physical activity measures. Results Nine studies met the review's inclusion criteria. Community-based recruitment approaches were widely used, and all studies employed cultural adaptation to varying degrees. Most studies reported improvements in PA outcomes, focused on Chinese Americans, and relied on self-reports of PA, while few aimed to increase PA using a multi-component approach. Conclusions Future studies would benefit from larger sample sizes, a wider representation of Asian ethnic subgroups, and concentrated efforts to implement deep level adaptations that may increase the salience and sustainability of these interventions.
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- 2018
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11. New considerations for hiPSC-based models of neuropsychiatric disorders
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Nadine Schrode, Gabriel E. Hoffman, Kristen J. Brennand, and Erin Flaherty
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0301 basic medicine ,Future studies ,Induced Pluripotent Stem Cells ,psychiatric disease ,Genomics ,Computational biology ,Biology ,Models, Biological ,Article ,transcriptomics ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Human disease ,Humans ,CRISPR ,Induced pluripotent stem cell ,Molecular Biology ,Neurons ,Extramural ,Mental Disorders ,Reproducibility of Results ,Cell Differentiation ,Human induced pluripotent stem cells ,3. Good health ,complex genetic disorders ,Psychiatry and Mental health ,Phenotype ,030104 developmental biology ,Critical power ,030217 neurology & neurosurgery - Abstract
The development of human induced pluripotent stem cells (hiPSCs) has made possible patient-specific modeling across the spectrum of human disease. Here we discuss recent advances in psychiatric genomics and post-mortem studies that provide critical insights concerning cell type composition and sample size that should be considered when designing hiPSC-based studies of complex genetic disease. We review recent hiPSC-based models of SZ, in light of our new understanding of critical power limitations in the design of hiPSC-based studies of complex genetic disorders. Three possible solutions are a movement towards genetically stratified cohorts of rare variant patients, application of CRISPR technologies to engineer isogenic neural cells to study the impact of common variants, and integration of advanced genetics and hiPSC-based datasets in future studies. Overall, we emphasize that to advance the reproducibility and relevance of hiPSC-based studies, stem cell biologists must contemplate statistical and biological considerations that are already well accepted in the field of genetics. We conclude with a discussion of the hypothesis of biological convergence of disease - through molecular, cellular, circuit and patient level phenotypes - and how this might emerge through hiPSC-based studies.
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- 2018
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12. Patient-derived hiPSC neurons with heterozygous CNTNAP2 deletions display altered neuronal gene expression and network activity
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Arthur J. Siegel, Elena Artimovich, Inkyu S. Lee, Kristen J. Brennand, Erin Flaherty, Deborah L. Levy, Rania M. Deranieh, and Michael W. Nestor
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0301 basic medicine ,Genetics ,CNTNAP2 ,lcsh:RC435-571 ,Synaptogenesis ,Neurexin ,Biology ,Brief Communication ,Neural stem cell ,03 medical and health sciences ,Psychiatry and Mental health ,030104 developmental biology ,0302 clinical medicine ,lcsh:Psychiatry ,Gene expression ,Premovement neuronal activity ,Axon guidance ,Gene ,030217 neurology & neurosurgery - Abstract
Variants in CNTNAP2, a member of the neurexin family of genes that function as cell adhesion molecules, have been associated with multiple neuropsychiatric conditions such as schizophrenia, autism spectrum disorder and intellectual disability; animal studies indicate a role for CNTNAP2 in axon guidance, dendritic arborization and synaptogenesis. We previously reprogrammed fibroblasts from a family trio consisting of two carriers of heterozygous intragenic CNTNAP2 deletions into human induced pluripotent stem cells (hiPSCs) and described decreased migration in the neural progenitor cells (NPCs) differentiated from the affected CNTNAP2 carrier in this trio. Here, we report the effect of this heterozygous intragenic deletion in CNTNAP2 on global gene expression and neuronal activity in the same cohort. Our findings suggest that heterozygous CNTNAP2 deletions affect genes involved in neuronal development and neuronal activity; however, these data reflect only one family trio and therefore more deletion carriers, with a variety of genetic backgrounds, will be needed to understand the molecular mechanisms underlying CNTNAP2 deletions.
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- 2017
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13. Chromatin profiling in human neurons reveals aberrant roles for histone acetylation and BET family proteins in schizophrenia
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Lorna A. Farrelly, Shuangping Zheng, Nadine Schrode, Aaron Topol, Natarajan V. Bhanu, Ryan M. Bastle, Aarthi Ramakrishnan, Jennifer C Chan, Bulent Cetin, Erin Flaherty, Li Shen, Kelly Gleason, Carol A. Tamminga, Benjamin A. Garcia, Haitao Li, Kristen J. Brennand, and Ian Maze
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Neurons ,Multidisciplinary ,Induced Pluripotent Stem Cells ,General Physics and Astronomy ,Nuclear Proteins ,Acetylation ,Cell Cycle Proteins ,Nerve Tissue Proteins ,Receptors, Cell Surface ,General Chemistry ,General Biochemistry, Genetics and Molecular Biology ,Chromatin ,Histones ,Schizophrenia ,Humans ,Protein Processing, Post-Translational ,Transcription Factors - Abstract
Schizophrenia (SZ) is a psychiatric disorder with complex genetic risk dictated by interactions between hundreds of risk variants. Epigenetic factors, such as histone posttranslational modifications (PTMs), have been shown to play critical roles in many neurodevelopmental processes, and when perturbed may also contribute to the precipitation of disease. Here, we apply an unbiased proteomics approach to evaluate combinatorial histone PTMs in human induced pluripotent stem cell (hiPSC)-derived forebrain neurons from individuals with SZ. We observe hyperacetylation of H2A.Z and H4 in neurons derived from SZ cases, results that were confirmed in postmortem human brain. We demonstrate that the bromodomain and extraterminal (BET) protein, BRD4, is a bona fide ‘reader’ of H2A.Z acetylation, and further provide evidence that BET family protein inhibition ameliorates transcriptional abnormalities in patient-derived neurons. Thus, treatments aimed at alleviating BET protein interactions with hyperacetylated histones may aid in the prevention or treatment of SZ.
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- 2020
14. ASCL1- and DLX2-induced GABAergic neurons from hiPSC-derived NPCs
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Samuel K. Powell, Erin Flaherty, Michael B. Fernando, Jubao Duan, Hanwen Zhang, Paul A. Slesinger, Seok-Man Ho, Siwei Zhang, Natalie Barretto, and Kristen J. Brennand
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0301 basic medicine ,education.field_of_study ,Somatic cell ,General Neuroscience ,Population ,Context (language use) ,Biology ,Neural stem cell ,Article ,03 medical and health sciences ,ASCL1 ,030104 developmental biology ,0302 clinical medicine ,Directed differentiation ,GABAergic ,education ,Reprogramming ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Background Somatic cell reprogramming is routinely used to generate donor-specific human induced pluripotent stem cells (hiPSCs) to facilitate studies of disease in a human context. The directed differentiation of hiPSCs can generate large quantities of patient-derived cells; however, such methodologies frequently yield heterogeneous populations of neurons and glia that require extended timelines to achieve electrophysiological maturity. More recently, transcription factor-based induction protocols have been show to rapidly generate defined neuronal populations from hiPSCs. New method In a manner similar to our previous adaption of NGN2-glutamatergic neuronal induction from hiPSC-derived neural progenitor cells (NPCs), we now adapt an established protocol of lentiviral overexpression of ASCL1 and DLX2 to hiPSC-NPCs. Results We demonstrate induction of a robust and highly pure population of functional GABAergic neurons (iGANs). Importantly, we successfully applied this technique to hiPSC-NPCs derived from ten donors across two independent laboratories, finding it to be an efficient and highly reproducible approach to generate induced GABAergic neurons. Our results show that, like hiPSC-iGANs, NPC-iGANs exhibit increased GABAergic marker expression, electrophysiological maturity, and have distinct transcriptional profiles that distinguish them from other cell-types of the brain. Nonetheless, until donor-matched hiPSCs-iGANs and NPC-iGANs are directly compared, we cannot rule out the possibility that subtle differences in patterning or maturity may exist between these populations; one should always control for cell source in all iGAN experiments. Conclusions This methodology, relying upon an easily cultured starting population of hiPSC-NPCs, makes possible the generation of large-scale defined co-cultures of induced glutamatergic and GABAergic neurons for hiPSC-based disease models and precision drug screening.
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- 2019
15. College Warrior Athlete Initiative and academic nursing
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Erin Flaherty, Katelyn Leestma, Paulette Thabault, Ann Wolbert Burgess, and Llynne C. Kiernan
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Adult ,Male ,050103 clinical psychology ,Universities ,Health Promotion ,Occupational culture ,Peer Group ,03 medical and health sciences ,0302 clinical medicine ,Nursing ,Humans ,0501 psychology and cognitive sciences ,Interpersonal Relations ,030212 general & internal medicine ,Students ,Exercise ,Veterans ,biology ,Athletes ,05 social sciences ,Public Health, Environmental and Occupational Health ,Physical health ,biology.organism_classification ,Mental health ,United States ,Health promotion ,Female ,Student athletes ,Psychology - Abstract
The College Warrior Athlete Initiative (CWAI) determined if a key element of military occupational culture, referred to as the "battle-buddy" concept of pairing college athletes with veterans, could be applied to Student Service Members/Veterans (SSM/V) health promotion.
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- 2019
16. Septic Arthritis and Joint Aspiration: The Radiologist's Role in Image-Guided Aspiration for Suspected Septic Arthritis
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Felix S. Chew, Jack Porrino, Hyojeong Mulcahy, Alice S. Ha, Erin Flaherty, Michael L. Richardson, and Mahmood Albahhar
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Suction (medicine) ,medicine.medical_specialty ,Arthritis, Infectious ,business.industry ,General surgery ,Arthritis ,Soft tissue ,Contrast Media ,Suction ,medicine.disease ,Skeletal radiology ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Joint aspiration ,0302 clinical medicine ,030220 oncology & carcinogenesis ,Cellulitis ,Surveys and Questionnaires ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Septic arthritis ,Practice Patterns, Physicians' ,Abscess ,business - Abstract
Introduction We sought to identify trends in variables that may serve as contraindications to performing image-guided joint aspiration for suspected septic arthritis. Methods A 17-question survey addressing scenarios encountered during a joint aspiration for suspected septic arthritis was distributed to 2017 members of the Society of Skeletal Radiology. Results 249 SSR members performed the survey. Cluster analysis identified 4 groups from the data. Conclusion Radiologists are mixed with regards to how commonly encountered variables alter their decision to perform an aspiration. Most notably, how to proceed when inflamed soft tissue overlies the needle path is not clear based on results.
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- 2019
17. Neuronal impact of patient-specific aberrant NRXN1α splicing
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Michael B. Fernando, Natalie Barretto, Kristen J. Brennand, Nadine Schrode, Esther Cheng, Robert Sebra, Gintaras Deikus, Megan L. Fitzgerald, Robert E. McCullumsmith, Erin Flaherty, P J Michael Deans, Peter Gochman, Nancy Francoeur, Judith L. Rapoport, Hardik Shah, Ian Ladran, Alesia Antoine, Nadejda M. Tsankova, Shijia Zhu, Gabriel E. Hoffman, Madeline Halpern, Khaled Alganem, and Gang Fang
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Gene isoform ,Male ,Heterozygote ,Bipolar Disorder ,Autism Spectrum Disorder ,Mutant ,Induced Pluripotent Stem Cells ,Gene Expression ,Biology ,Article ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Gene expression ,Genetics ,Premovement neuronal activity ,Animals ,Humans ,Protein Isoforms ,Induced pluripotent stem cell ,Neural Cell Adhesion Molecules ,030304 developmental biology ,Sequence Deletion ,0303 health sciences ,Depressive Disorder, Major ,Alternative splicing ,Calcium-Binding Proteins ,Phenotype ,Cell biology ,Alternative Splicing ,Case-Control Studies ,RNA splicing ,Schizophrenia ,Female ,030217 neurology & neurosurgery - Abstract
NRXN1 undergoes extensive alternative splicing, and non-recurrent heterozygous deletions in NRXN1 are strongly associated with neuropsychiatric disorders. We establish that human induced pluripotent stem cell (hiPSC)-derived neurons represent well the diversity of NRXN1α alternative splicing observed in the human brain, cataloguing 123 high-confidence in-frame human NRXN1α isoforms. Patient-derived NRXN1+/− hiPSC-neurons show greater than two-fold reduction of half of the wild-type NRXN1α isoforms and express dozens of novel isoforms expressed from the mutant allele. Reduced neuronal activity in patient-derived NRXN1+/− hiPSC-neurons is ameliorated by overexpression of individual control isoforms in a genotype-dependent manner, whereas individual mutant isoforms decrease neuronal activity levels in control hiPSC-neurons. In a genotype-dependent manner, the phenotypic impact of patient-specific NRXN1+/− mutations can occur through a reduction in wild-type NRXN1α isoform levels as well as the presence of mutant NRXN1α isoforms.
- Published
- 2019
18. Ultra-Rare Exonic Variants Identified in a Founder Population Implicate Cadherins and Protocadherins in Schizophrenia
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Max Lam, Jin Yu, Anil K. Malhotra, Raiyan R. Khan, Erin Flaherty, Todd Lencz, Gil Atzmon, Itsik Pe'er, and Tom Maniatis
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Genetics ,Cadherin ,Schizophrenia (object-oriented programming) ,Biology ,Biological Psychiatry ,Founder effect - Published
- 2021
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19. THC Treatment Alters Glutamate Receptor Gene Expression in Human Stem Cell-Derived Neurons
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Erin Flaherty, Khalifa Stafford, Kristen J. Brennand, Ifeanyi Obiorah, and Hamza Muhammad
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0301 basic medicine ,Original Paper ,biology ,organic chemicals ,medicine.medical_treatment ,Glutamate receptor ,General Medicine ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,mental disorders ,medicine ,biology.protein ,GRIN2A ,GRIN2B ,Cannabinoid ,GRIA2 ,Stem cell ,Induced pluripotent stem cell ,Neuroscience ,GRIA1 ,030217 neurology & neurosurgery - Abstract
Given the cognitive and behavioral effects following in utero Δ9-tetrahydrocannabinol (THC) exposure that have been reported in humans and rodents, it is critical to understand the precise consequences of THC on developing human neurons. Here, we utilize excitatory neurons derived from human-induced pluripotent stem cells (hiPSCs), and report that in vitro THC exposure reduced expression of glutamate receptor subunit genes (GRIA1, GRIA2, GRIN2A, and GRIN2B). By expanding these studies across hiPSC-derived neurons from individuals with a variety of genotypes, we believe that a hiPSC-based model will facilitate studies of the interaction of THC exposure and the genetic risk factors underlying neuropsychiatric disease vulnerability.
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- 2017
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20. Using hiPSCs to model neuropsychiatric copy number variations (CNVs) has potential to reveal underlying disease mechanisms
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Kristen J. Brennand and Erin Flaherty
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0301 basic medicine ,Genetics ,DNA Copy Number Variations ,Mental Disorders ,General Neuroscience ,Schizophrenia (object-oriented programming) ,Induced Pluripotent Stem Cells ,Context (language use) ,Biology ,Article ,Genetic architecture ,03 medical and health sciences ,030104 developmental biology ,Genome editing ,Genetically Engineered Mouse ,Animals ,Humans ,Identification (biology) ,Neurology (clinical) ,Copy-number variation ,Induced pluripotent stem cell ,Molecular Biology ,Developmental Biology - Abstract
Schizophrenia is a neuropsychological disorder with a strong heritable component; genetic risk for schizophrenia is conferred by both common variants of relatively small effect and rare variants with high penetrance. Genetically engineered mouse models can recapitulate rare variants, displaying some behavioral defects associated with schizophrenia; however, these mouse models cannot recapitulate the full genetic architecture underlying the disorder. Patient-derived human induced pluripotent stem cells (hiPSCs) present an alternative approach for studying rare variants, in the context of all other risk alleles. Genome editing technologies, such as CRISPR-Cas9, enable the generation of isogenic hiPSC lines with which to examine the functional contribution of single variants within any genetic background. Studies of these rare variants using hiPSCs have the potential to identify commonly disrupted pathways in schizophrenia and allow for the identification of new therapeutic targets. This article is part of a Special Issue entitled SI:StemsCellsinPsychiatry.
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- 2017
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21. Sex-Specific Role for the Long Non-coding RNA LINC00473 in Depression
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Yentl Y. van der Zee, Li Shen, Catherine Jensen Pena, Yan Dong, Orna Issler, Angélica Torres-Berrío, Benoit Labonté, Zachary S. Lorsch, Chunfeng Tan, Julia E. Duffy, Brigham J. Hartley, Kristen J. Brennand, Eric M. Parise, Erin Flaherty, Junshi Wang, Peter J. Hamilton, Yong-Hwee E. Loh, Immanuel Purushothaman, Rachael L. Neve, Eric J. Nestler, Deena M. Walker, Hope Kronman, Aarthi Ramakrishnan, Molly Estill, Erin S. Calipari, Carol A. Tamminga, Psychiatrie & Neuropsychologie, and RS: MHeNs - R3 - Neuroscience
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Male ,0301 basic medicine ,STRESS ,PREFRONTAL CORTEX ,SUSCEPTIBILITY ,Social defeat ,Mice ,0302 clinical medicine ,SOCIAL DEFEAT ,Gene expression ,RNA-Seq ,TRANSCRIPTION ,Prefrontal cortex ,Aged, 80 and over ,Neurons ,Behavior, Animal ,biology ,Depression ,Effector ,General Neuroscience ,LOCALIZATION ,Middle Aged ,Resilience, Psychological ,Phenotype ,Long non-coding RNA ,Female ,RNA, Long Noncoding ,Adult ,medicine.medical_specialty ,Down-Regulation ,UNIQUE FEATURES ,Mice, Transgenic ,CREB ,Young Adult ,03 medical and health sciences ,Sex Factors ,Internal medicine ,medicine ,Animals ,Humans ,Gene ,Aged ,Depressive Disorder, Major ,GENOME-WIDE ,EVOLUTION ,030104 developmental biology ,Endocrinology ,CELLS ,biology.protein ,Stress, Psychological ,030217 neurology & neurosurgery - Abstract
Depression is a common disorder that affects women at twice the rate of men. Here, we report that long non-coding RNAs (lncRNAs), a recently discovered class of regulatory transcripts, represent about one-third of the differentially expressed genes in the brains of depressed humans and display complex region- and sex-specific patterns of regulation. We identified the primate-specific, neuronal-enriched gene LINC00473 as downregulated in prefrontal cortex (PFC) of depressed females but not males. Using viral-mediated gene transfer to express LINC00473 in adult mouse PFC neurons, we mirrored the human sex-specific phenotype by inducing stress resilience solely in female mice. This sex-specific phenotype was accompanied by changes in synaptic function and gene expression selectively in female mice and, along with studies of human neuron-like cells in culture, implicates LINC00473 as a CREB effector. Together, our studies identify LINC00473 as a female-specific driver of stress resilience that is aberrant in female depression. Issler et al. demonstrate that long non-coding RNAs are robustly regulated in the brains of postmortem depressed humans in a brain site- and sex-specific manner. LINC00473 is highlighted as key regulator of mood in females only, where it acts in prefrontal cortex by regulating gene expression, neurophysiology, and behavior.
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- 2020
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22. T9. EPIGENETIC PROFILING IN SCHIZOPHRENIA DERIVED HUMAN INDUCED PLURIPOTENT STEM CELLS (HIPSCS) AND NEURONS
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Ryan M. Bastle, Erin Flaherty, Haitao Li, Lorna A. Farrelly, Ian Maze, Benjamin A. Garcia, Aaron Topol, Shuangping Zhang, Natarajan V. Bhanu, Nadine Schrode, and Kristen J. Brennand
- Subjects
Psychiatry and Mental health ,Poster Session III ,AcademicSubjects/MED00810 ,Profiling (information science) ,Epigenetics ,Human Induced Pluripotent Stem Cells ,Biology ,Neuroscience - Abstract
Background Schizophrenia (SCZ) is a severe psychiatric disorder affecting ~1% of the world’s population. It is largely heritable with genetic risk reflected by a combination of common variants of small effect and highly penetrant rare mutations. Chromatin modifications are known to play critical roles in the mediation of many neurodevelopmental processes, and, when disturbed, may also contribute to the precipitation of psychiatric disorders, such as SCZ. While a handful of candidate-based studies have measured changes in promoter-bound histone modifications, few mechanistic studies have been carried out to explore how these modifications may affect chromatin to precipitate behavioral phenotypes associated with the disease. Methods We applied an unbiased proteomics approach to evaluate the epigenetic landscape of SCZ in human induced pluripotent stem cells (hiPSC), neural progenitor cells (NPCs) and neurons from SCZ patients vs. matched controls. We utilized proteomics-based, label free liquid chromatography mass spectrometry (LC-MS/MS) on purified histones from these cells and confirmed our results by western blotting in postmortem SCZ cortical brain tissues. Furthermore we validated our findings with the application of histone interaction assays and structural and biophysical assessments to identify and confirm novel chromatin ‘readers’. To relate our findings to a SCZ phenotype we used a SCZ rodent model of prepulse inhibition (PPI) to perform pharmacological manipulations and behavioral assessments. Results Using label free mass spectrometry we performed PTM screening of hiPSCs, NPCs and matured neurons derived from SCZ patients and matched controls. We identified, amongst others, altered patterns of hyperacetylation in SCZ neurons. Additionally we identified enhanced binding of particular acetylation ‘reader’ proteins. Pharmacological inhibition of such proteins in an animal model of amphetamine sensitization ameliorated PPI deficits further validating this epigenetic signature in SCZ. Discussion Recent evidence indicates that relevance and patterns of acetylation in epigenetics advances beyond its role in transcription and small molecule inhibitors of these aberrant interactions hold promise as useful therapeutics. This study identifies a role for modulating gene expression changes associated with a SCZ epigenetic signature and warrants further investigation in terms of how this early gene expression pattern perhaps determines susceptibility or severity of the SCZ disease trajectory.
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- 2020
23. Neuron-specific signatures in the chromosomal connectome associated with schizophrenia risk
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Tyler M. Borrman, Samuel K. Powell, Gabriel E. Hoffman, Panos Roussos, Elizabeth A. LaMarca, Charlize Casiño, Bin Zhang, Schahram Akbarian, Zhiping Weng, Prashanth Rajarajan, Bibi Kassim, Daniel H. Geschwind, Chittampalli Yashaswini, Seok-Man Ho, Nadine Schrode, Kristen J. Brennand, Sergio Espeso-Gil, Erin Flaherty, Hyejung Won, Will Liao, Aiqun Li, Behnam Javidfar, Matthew L. MacDonald, and Chang-Gyu Hahn
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Male ,Proteomics ,0301 basic medicine ,Transcription, Genetic ,Genome-wide association study ,Genome ,Epigenesis, Genetic ,Transcriptome ,Neural Stem Cells ,2.1 Biological and endogenous factors ,Chromosomes, Human ,Developmental ,Protein Interaction Maps ,Cells, Cultured ,Genomic organization ,Neurons ,Regulation of gene expression ,Genetics ,Cultured ,Multidisciplinary ,Brain ,Gene Expression Regulation, Developmental ,Chromatin ,Mental Health ,Neurological ,Connectome ,Transcription ,Neuroglia ,Human ,Risk ,General Science & Technology ,Cells ,1.1 Normal biological development and functioning ,Neurogenesis ,Biology ,Chromosomes ,Article ,Chromatin remodeling ,03 medical and health sciences ,Genetic ,MD Multidisciplinary ,Humans ,Genetic Predisposition to Disease ,Gene ,Genome, Human ,Prevention ,Human Genome ,Neurosciences ,Stem Cell Research ,Chromatin Assembly and Disassembly ,Brain Disorders ,030104 developmental biology ,Gene Expression Regulation ,Schizophrenia ,Nucleic Acid Conformation ,Epigenesis ,Genome-Wide Association Study - Abstract
INTRODUCTION Chromosomal conformations, topologically associated chromatin domains (TADs) assembling in nested fashion across hundreds of kilobases, and other “three-dimensional genome” (3DG) structures bypass the linear genome on a kilo- or megabase scale and play an important role in transcriptional regulation. Most of the genetic variants associated with risk for schizophrenia (SZ) are common and could be located in enhancers, repressors, and other regulatory elements that influence gene expression; however, the role of the brain’s 3DG for SZ genetic risk architecture, including developmental and cell type–specific regulation, remains poorly understood. RATIONALE We monitored changes in 3DG after isogenic differentiation of human induced pluripotent stem cell–derived neural progenitor cells (NPCs) into neurons or astrocyte-like glial cells on a genome-wide scale using Hi-C. With this in vitro model of brain development, we mapped cell type–specific chromosomal conformations associated with SZ risk loci and defined a risk-associated expanded genome space. RESULTS Neural differentiation was associated with genome-wide 3DG remodeling, including pruning and de novo formations of chromosomal loopings. The NPC-to-neuron transition was defined by the pruning of loops involving regulators of cell proliferation, morphogenesis, and neurogenesis, which is consistent with a departure from a precursor stage toward postmitotic neuronal identity. Loops lost during NPC-to-glia transition included many genes associated with neuron-specific functions, which is consistent with non-neuronal lineage commitment. However, neurons together with NPCs, as compared with glia, harbored a much larger number of chromosomal interactions anchored in common variant sequences associated with SZ risk. Because spatial 3DG proximity of genes is an indicator for potential coregulation, we tested whether the neural cell type–specific SZ-related “chromosomal connectome” showed evidence of coordinated transcriptional regulation and proteomic interaction of the participating genes. To this end, we generated lists of genes anchored in cell type–specific SZ risk-associated interactions. Thus, for the NPC-specific interactions, we counted 386 genes, including 146 within the risk loci and another 240 genes positioned elsewhere in the linear genome but connected via intrachromosomal contacts to risk locus sequences. Similarly, for the neuron-specific interactions, we identified 385 genes: 158 within risk loci and 227 outside of risk loci. Last, for glia-specific interactions, we identified 201 genes: 88 within and 113 outside of risk loci. We labeled the genes located outside of schizophrenia risk loci as “risk locus–connect,” which we define as a collection of genes identified only through Hi-C interaction data, expanding—depending on cell type—by 50 to 150% the current network of known genes overlapping risk sequences that is informed only by genome-wide association studies. This disease-related chromosomal connectome was associated with “clusters” of coordinated gene expression and protein interactions, with at least one cluster strongly enriched for regulators of neuronal connectivity and synaptic plasticity and another cluster for chromatin-associated proteins, including transcriptional regulators. CONCLUSION Our study shows that neural differentiation is associated with highly cell type–specific 3DG remodeling. This process is paralleled by an expansion of 3DG space associated with SZ risk. Specifically, developmentally regulated chromosomal conformation changes at SZ-relevant sequences disproportionally occurred in neurons, highlighting the existence of cell type–specific disease risk vulnerabilities in spatial genome organization. 3DG remodeling across neuronal differentiation with parallel expansion of SZ risk space. (Left) Chromatin conformation assays reveal pruning of short-range loops in neurons along with widening of TADs upon differentiation from NPCs. (Right) Cell type–specific chromatin interactions, functionally validated with CRISPR assays, expand the network of known risk-associated genes (blue circle), which show evidence for coregulation at the transcriptomic and proteomic levels.
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- 2018
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24. Cross-Sectional Imaging of Renal Masses: Image Interpretation–Related Potential Pitfalls and Possible Solutions
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Srinivasa R. Prasad, Venkata S. Katabathina, Erin Flaherty, and Jay C Shiao
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Diagnostic Imaging ,medicine.medical_specialty ,Angiomyolipoma ,Liposarcoma ,Kidney ,030218 nuclear medicine & medical imaging ,Cross-sectional imaging ,03 medical and health sciences ,0302 clinical medicine ,Renal cell carcinoma ,Image Interpretation, Computer-Assisted ,Medical imaging ,medicine ,Humans ,Image acquisition ,Radiology, Nuclear Medicine and imaging ,Diagnostic Errors ,Ultrasonography ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,medicine.disease ,Magnetic Resonance Imaging ,Kidney Neoplasms ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Radiology ,Tomography, X-Ray Computed ,business - Abstract
Introduction After identifying and correcting pitfalls related to image acquisition, radiologists should focus their attention on the potential errors that can occur during image interpretation. Among them, thefirst andmost important one is inappropriate characterization of a focus of normal renal tissue, congenital variant, or a benign infectious or inflammatory condition as a renal neoplasmon imaging studies. Secondly, identification of fat within a solid renalmass can create problems in distinguishing benign angiomyolipoma (AML) from malignant entities such as renal cell carcinoma (RCC) and liposarcoma. Thirdly, inappropriate assessment of contrast enhancement in solid or cystic masses, especially in hyperattenuating and heavily calcified renal masses, may pose significant problems that result in a faulty interpretation of a benign neoplasm as a malignant one and vice versa. In this article, we would review potential errors that radiologistsmay encounter during interpretation of ultrasound (US), multiple detector computed tomography (MDCT), and magnetic resonance imaging (MRI) studies in patients with renal masses and provide possible solutions to overcome these pitfalls.
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- 2016
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25. Transcriptional signatures of schizophrenia in hiPSC-derived NPCs and neurons are concordant with signatures from post mortem adult brains
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Eli A. Stahl, Gabriel E. Hoffman, Douglas M. Ruderfer, Brigham J. Hartley, Pamela Sklar, Kristen J. Brennand, Peter Gochman, Erin Flaherty, Judith L. Rapoport, and Ian Ladran
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Genetics ,0303 health sciences ,Cell type ,Cell type composition ,Concordance ,Computational biology ,Biology ,medicine.disease ,Neural stem cell ,03 medical and health sciences ,0302 clinical medicine ,Schizophrenia ,medicine ,Genetic risk ,Induced pluripotent stem cell ,030217 neurology & neurosurgery ,030304 developmental biology - Abstract
Whereas highly penetrant variants have proven well-suited to human induced pluripotent stem cell (hiPSC)-based models, the power of hiPSC-based studies to resolve the much smaller effects of common variants within the size of cohorts that can be realistically assembled remains uncertain. In developing a large case/control schizophrenia (SZ) hiPSC-derived cohort of neural progenitor cells and neurons, we identified and accounted for a variety of technical and biological sources of variation. Reducing the stochastic effects of the differentiation process by correcting for cell type composition boosted the SZ signal in hiPSC-based models and increased the concordance with post mortem datasets. Because this concordance was strongest in hiPSC-neurons, it suggests that this cell type may better model genetic risk for SZ. We predict a growing convergence between hiPSC and post mortem studies as both approaches expand to larger cohort sizes. For studies of complex genetic disorders, to maximize the power of hiPSC cohorts currently feasible, in most cases and whenever possible, we recommend expanding the number of individuals even at the expense of the number of replicate hiPSC clones.
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- 2017
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26. Adrenal collision tumors and their mimics: multimodality imaging findings
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Vijayanadh Ojili, Venkata S. Katabathina, Ravi K. Kaza, Kedar N. Chintapalli, Srinivasa R. Prasad, and Erin Flaherty
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Myelolipoma ,medicine.medical_specialty ,Adenoma ,Biopsy ,Adrenal Gland Neoplasms ,multidetector computed tomography ,positron emission tomography/computed tomography ,Review ,Multimodal Imaging ,Adrenal collision tumors ,Hemangioma ,Diagnosis, Differential ,Neoplasms, Multiple Primary ,medicine ,Adrenocortical carcinoma ,Humans ,Radiology, Nuclear Medicine and imaging ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,Adrenal gland ,business.industry ,Magnetic resonance imaging ,General Medicine ,medicine.disease ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Oncology ,Positron-Emission Tomography ,Radiology ,business ,Tomography, X-Ray Computed ,Preclinical imaging - Abstract
Adrenal collision tumors (ACTs) refer to coexistence of two adjacent, but histologically distinct neoplasms involving the adrenal gland without histologic admixture at interface. ACTs include adenoma with myelolipoma, adenoma with metastases, hemangioma with adenoma, and adrenocortical carcinoma with myelolipoma. In addition, hemorrhage into a pre-existing adrenal mass can mimic an ACT, and it is important to differentiate these two pathologies. Accurate characterization of ACTs is difficult, but critical, for correct staging of patients with malignancies and to guide percutaneous biopsy. Magnetic resonance imaging (MRI) and multidetector computed tomography imaging techniques may depict different tumor components separately; however, biopsy may be required in selected patients for confirmation. [18F]Fluorodeoxyglucose-positron emission tomography (PET) shows increased uptake in the malignant component of ACTs, and guides percutaneous biopsy. Even in patients requiring percutaneous biopsy for a definite diagnosis, imaging findings can help in guiding the appropriate component to be biopsied. Knowledge of imaging findings of different ACTs and their mimics on MRI, computed tomography, and PET help in optimal patient management.
- Published
- 2013
27. Emergency Imaging of Foot Trauma
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Felix S. Chew and Erin Flaherty
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030222 orthopedics ,medicine.medical_specialty ,business.industry ,Foot ,Radiography ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Tomography x ray computed ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Radiology ,Tomography ,Foot Injury ,business ,Emergency Service, Hospital ,Foot Injuries ,Tomography, X-Ray Computed ,Foot (unit) - Published
- 2016
28. Cross-Sectional Imaging of Renal Masses: Imaging Technique-Related Potential Pitfalls and Solutions
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Srinivasa R. Prasad, Erin Flaherty, and Venkata S. Katabathina
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Diagnostic Imaging ,Renal lesion ,medicine.medical_specialty ,Kidney ,030218 nuclear medicine & medical imaging ,Cross-sectional imaging ,03 medical and health sciences ,0302 clinical medicine ,Multidetector Computed Tomography ,Medical imaging ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Diagnostic Errors ,Ultrasonography ,Modality (human–computer interaction) ,medicine.diagnostic_test ,business.industry ,Ultrasound ,Magnetic resonance imaging ,Magnetic Resonance Imaging ,Kidney Neoplasms ,030220 oncology & carcinogenesis ,Imaging technique ,Radiology ,business - Abstract
Introduction There has been an exponential increase in the incidental detection of renal masses that is commensurate with the increasing use of cross-sectional studies for evaluation of awide spectrum of patient symptoms. This increased detection of renal lesions necessitates better characterization to allowproper management. Ultrasound or ultrasonography (US), multidetector-row computed tomography (MDCT), and magnetic resonance imaging (MRI) are the modalities currently available for renal lesion detection, localization, and characterization. Standardized, multiphase CT and MRI protocols have been developed to allow reliable and reproducible lesion characterization. However, suboptimal image quality or nonstandard imaging techniquesmay create challenges in both the detection of masses as well as their accurate diagnosis. In this article, we present potential image acquisition–related pitfalls and possible solutions in the detection and assessment of renal masses in adult patients. Improved knowledge regarding such potential pitfalls may help radiologists to choose a different imaging modality or repeat the same study with technique modifications.
- Published
- 2016
29. TRANSCRIPTIONAL SIGNATURES OF CHILDHOOD ONSET SCHIZOPHRENIA IN HIPSC-DERIVED NPCS AND NEURONS ARE CONCORDANT WITH SIGNATURES FROM POST MORTEM ADULT BRAINS
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Gabriel E. Hoffman, Doug Ruderfer, Erin Flaherty, Kristen J. Brennand, Brigham J. Hartley, Peter Gochman, Pamela Sklar, Judith L. Rapoport, and Ian Ladran
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Pharmacology ,Genome-wide association study ,Computational biology ,Quantitative trait locus ,Biology ,medicine.disease ,Neural stem cell ,Correlation ,Psychiatry and Mental health ,Neurology ,Schizophrenia ,medicine ,Pharmacology (medical) ,Neurology (clinical) ,Copy-number variation ,Induced pluripotent stem cell ,Reprogramming ,Biological Psychiatry - Abstract
Background Large-scale Genome Wide Association Studies (GWAS) revealed that Schizophrenia (SZ) risk reflects both rare and common variants. Whereas highly penetrant rare variants have proven well-suited to human induced pluripotent stem cell (hiPSC)-based models, the power of hiPSC-based studies to resolve the much smaller effects of common variants within the size of cohorts that can be realistically assembled remains uncertain. Childhood-Onset-SZ (COS) patients have both a higher rate of rare SZ-associated Copy Number Variations (CNVs), and also stronger common SZ polygenic risk scores. Methods We developed a case/control hiPSC cohort (12 individuals with COS and 10 controls) with which to conduct a comprehensive evaluation of global gene expression in hiPSC-derived neural progenitor cells (NPCs) and neurons. Results Although we identified many sources of variation across our 94 RNAseq samples, this was partially addressed by establishing a rigorous series of bioinformatic practices to reduce and assess the variance inherent in this approach. We report that the donor-specific signal is enriched for post- mortem brain Expression Quantitative Trait Loci (eQTLs), but also that there is a significant correlation between the case/control differential expression observed in our hiPSC-derived COS neurons and the CommonMind Consortium post-mortem study. While the issue of small sample size is shared between post-mortem and hiPSC-based studies, and may be exacerbated in hiPSC-based experiments through the variability that arises as a result of the reprogramming and neural differentiation processes, we find that the common variation effects predicted in GWAS and detected in much larger post-mortem analyses are reflected in hiPSC-neurons. Discussion We predict a growing convergence of common variation findings between hiPSC and post-mortem studies as both approaches expand to larger cohort sizes.
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- 2019
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30. MODELING THE IMPACT OF RARE AND COMMON VARIANTS ON PREDISPOSITION TO SCHIZOPHRENIA USING STEM CELLS
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Nadine Schrode, Erin Flaherty, Seok-Man Ho, Gabriel E. Hoffman, and Kristen J. Brennand
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Pharmacology ,Psychiatry and Mental health ,Neurology ,Schizophrenia (object-oriented programming) ,Pharmacology (medical) ,Neurology (clinical) ,Biology ,Stem cell ,Bioinformatics ,Biological Psychiatry - Published
- 2019
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31. 'Biliary Diseases with Pancreatic Counterparts': Cross-sectional Imaging Findings
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Yasuni Nakanuma, Kazuto Kozaka, Srinivasa R. Prasad, Erin Flaherty, Christine O. Menias, Osamu Matsui, Nicole D. Riddle, Anil K. Dasyam, Narayan Lath, and Venkata S. Katabathina
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Pathology ,medicine.medical_specialty ,Biliary Tract Diseases ,Cholangitis, Sclerosing ,Disease ,Epithelium ,Autoimmune Diseases ,Cholangiocarcinoma ,03 medical and health sciences ,0302 clinical medicine ,Fibrosis ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Autoimmune pancreatitis ,Intraductal papillary mucinous neoplasm ,business.industry ,Pancreatic Ducts ,Pancreatic Diseases ,medicine.disease ,Magnetic Resonance Imaging ,Cystic Neoplasm ,Pancreatic Neoplasms ,medicine.anatomical_structure ,Bile Duct Neoplasms ,Pancreatitis ,Biliary tract ,Organ Specificity ,030220 oncology & carcinogenesis ,Immunoglobulin G ,030211 gastroenterology & hepatology ,Bile Ducts ,business ,Pancreas ,Neoplasms, Cystic, Mucinous, and Serous ,Tomography, X-Ray Computed ,Carcinoma, Pancreatic Ductal - Abstract
On the basis of the similarities in the histopathologic findings and the clinical-biologic behaviors of select biliary and pancreatic conditions, a new disease concept, "biliary diseases with pancreatic counterparts," has been proposed. Both nonneoplastic and neoplastic pathologic conditions of the biliary tract have their counterparts in the pancreas. Immunoglobulin G4 (IgG4)-related sclerosing cholangitis is the biliary manifestation of IgG4-related sclerosing disease, and type 1 autoimmune pancreatitis is its pancreatic counterpart. People with chronic alcoholism can develop peribiliary cysts and fibrosis as well as pancreatic fibrosis and chronic pancreatitis simultaneously. Pancreatic ductal adenocarcinoma, intraductal papillary mucinous neoplasm, and mucinous cystic neoplasm are considered pancreatic counterparts for the biliary neoplasms of extrahepatic cholangiocarcinoma, intraductal papillary neoplasm of the biliary tract, and hepatic mucinous cystic neoplasm, respectively. The anatomic proximity of the biliary tract and the pancreas, the nearly simultaneous development of both organs from the endoderm of the foregut, and the presence of pancreatic exocrine acini within the peribiliary glands surrounding the extrahepatic bile ducts are suggested as causative factors for these similarities. Interestingly, these diseases show "nearly" identical findings at cross-sectional imaging, an observation that further supports this new disease concept. New information obtained with regard to biliary diseases can be used for evaluation of pancreatic abnormalities, and vice versa. In addition, combined genetic and molecular studies may be performed to develop novel therapeutic targets. For both biliary and pancreatic diseases, imaging plays a pivotal role in initial diagnosis, evaluation of treatment response, efficacy testing of novel drugs, and long-term surveillance.
- Published
- 2016
32. Increased abundance of translation machinery in stem cell–derived neural progenitor cells from four schizophrenia patients
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David Cotter, Kristen J. Brennand, Prashanth Rajarajan, Judith L. Rapoport, Jeffrey N. Savas, L Friedman, Bin Zhang, Aaron Topol, Gerard Cagney, Jane A. English, F Desland, Sounak Gupta, Bruce J. Aronow, Brigham J. Hartley, Alan Mackay-Sim, T Goff, D Felsenfeld, Shijia Zhu, Erin Flaherty, and Gang Fang
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Cellular differentiation ,Induced Pluripotent Stem Cells ,Biology ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Eukaryotic translation ,Prosencephalon ,Neural Stem Cells ,Protein biosynthesis ,Humans ,Epigenetics ,Induced pluripotent stem cell ,Biological Psychiatry ,Cells, Cultured ,030304 developmental biology ,Neurons ,0303 health sciences ,Translation (biology) ,Cell Differentiation ,Neural stem cell ,3. Good health ,Cell biology ,Psychiatry and Mental health ,Schizophrenia ,Original Article ,Stem cell ,Neuroscience ,030217 neurology & neurosurgery - Abstract
The genetic and epigenetic factors contributing to risk for schizophrenia (SZ) remain unresolved. Here we demonstrate, for the first time, perturbed global protein translation in human-induced pluripotent stem cell (hiPSC)-derived forebrain neural progenitor cells (NPCs) from four SZ patients relative to six unaffected controls. We report increased total protein levels and protein synthesis, together with two independent sets of quantitative mass spectrometry evidence indicating markedly increased levels of ribosomal and translation initiation and elongation factor proteins, in SZ hiPSC NPCs. We posit that perturbed levels of global protein synthesis in SZ hiPSC NPCs represent a novel post-transcriptional mechanism that might contribute to disease progression.
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- 2015
33. A Systematic Review of Culturally Specific Interventions to Increase Physical Activity for Older Asian Americans.
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Katigbak C, Flaherty E, Chao YY, Nguyen T, Cheung D, and Yiu-Cho Kwan R
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- Humans, Asian, Exercise, Health Behavior ethnology, Health Promotion methods
- Abstract
Background: Physical activity (PA) is a significant modifiable risk factor for cardiovascular disease. For older adults, engaging in PA is shown to improve cardiac status, reduce cognitive, and functional decline, and improve overall quality of life. However, only 17% of Asian American adults meet the 2008 federal recommended guidelines for aerobic and muscle strengthening activity; and there is a paucity of data reporting on older Asian Americans - a rapidly growing, underserved group. While data pertaining to Asian Americans is frequently reported at the aggregate level, this masks differences (eg, language, culture, income) among Asian ethnic subgroups that may impact health behaviors. The purpose of this review was to identify intervention, and cultural adaptation strategies in studies promoting PA for older Asian Americans., Methods: A comprehensive literature search was performed to identify interventions published between 1996-2016 focused on improving PA among older Asian Americans (> 60 years old). Data were abstracted to examine intervention study designs, cultural adaptation strategies, theoretical frameworks, and physical activity measures., Results: Nine studies met the review's inclusion criteria. Community-based recruitment approaches were widely used, and all studies employed cultural adaptation to varying degrees. Most studies reported improvements in PA outcomes, focused on Chinese Americans, and relied on self-reports of PA, while few aimed to increase PA using a multi-component approach., Conclusions: Future studies would benefit from larger sample sizes, a wider representation of Asian ethnic subgroups, and concentrated efforts to implement deep level adaptations that may increase the salience and sustainability of these interventions.
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- 2018
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