76
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Noever C, Olson A, Glenner H. Two new cryptic and sympatric species of the king crab parasite Briarosaccus (Cirripedia: Rhizocephala) in the North Pacific. Zool J Linn Soc 2016; 176:3-14. [PMID: 26792948 PMCID: PMC4706646 DOI: 10.1111/zoj.12304] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 06/01/2015] [Accepted: 06/10/2015] [Indexed: 12/04/2022]
Abstract
Rhizocephalan barnacles have been reported to parasitize a wide range of king crab species (Lithodidae). So far all these parasites have been assigned to a single species, Briarosaccus callosus Boschma, 1930, which is assumed to have a global distribution. Here we investigate Briarosaccus specimens from three different king crab hosts from the fjord systems of Southeastern Alaska: Lithodes aequispinus Benedict, 1895, Paralithodes camtschaticus (Tilesius, 1815), and Paralithodes platypus (Brandt, 1850). Using molecular markers and by morphological comparison we show that Briarosaccus specimens from these three commercial exploited king crabs are in fact morphologically distinct from B. callosus, and further represent two separate species which we describe. The two new species, Briarosaccus auratum n. sp. and B. regalis n. sp., are cryptic by morphological means and were identified as distinct species by the use of genetic markers (COI and 16S). They occur sympatrically, yet no overlap in king crab hosts occurs, with B. auratum n. sp. only found on L. aequispinus, and B. regalis n. sp. as parasite of the two Paralithodes hosts.
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77
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Hiu T, Farzampour Z, Paz JT, Wang EHJ, Badgely C, Olson A, Micheva KD, Wang G, Lemmens R, Tran KV, Nishiyama Y, Liang X, Hamilton SA, O'Rourke N, Smith SJ, Huguenard JR, Bliss TM, Steinberg GK. Enhanced phasic GABA inhibition during the repair phase of stroke: a novel therapeutic target. Brain 2015; 139:468-80. [PMID: 26685158 PMCID: PMC4805083 DOI: 10.1093/brain/awv360] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 10/20/2015] [Indexed: 11/13/2022] Open
Abstract
Ischaemic stroke is the leading cause of severe long-term disability yet lacks drug therapies that promote the repair phase of recovery. This repair phase of stroke occurs days to months after stroke onset and involves brain remapping and plasticity within the peri-infarct zone. Elucidating mechanisms that promote this plasticity is critical for the development of new therapeutics with a broad treatment window. Inhibiting tonic (extrasynaptic) GABA signalling during the repair phase was reported to enhance functional recovery in mice suggesting that GABA plays an important function in modulating brain repair. While tonic GABA appears to suppress brain repair after stroke, less is known about the role of phasic (synaptic) GABA during the repair phase. We observed an increase in postsynaptic phasic GABA signalling in mice within the peri-infarct cortex specific to layer 5; we found increased numbers of α1 receptor subunit-containing GABAergic synapses detected using array tomography, and an associated increased efficacy of spontaneous and miniature inhibitory postsynaptic currents in pyramidal neurons. Furthermore, we demonstrate that enhancing phasic GABA signalling using zolpidem, a Food and Drug Administration (FDA)-approved GABA-positive allosteric modulator, during the repair phase improved behavioural recovery. These data identify potentiation of phasic GABA signalling as a novel therapeutic strategy, indicate zolpidem’s potential to improve recovery, and underscore the necessity to distinguish the role of tonic and phasic GABA signalling in stroke recovery.
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78
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Tello-Ruiz MK, Stein J, Wei S, Preece J, Olson A, Naithani S, Amarasinghe V, Dharmawardhana P, Jiao Y, Mulvaney J, Kumari S, Chougule K, Elser J, Wang B, Thomason J, Bolser DM, Kerhornou A, Walts B, Fonseca NA, Huerta L, Keays M, Tang YA, Parkinson H, Fabregat A, McKay S, Weiser J, D'Eustachio P, Stein L, Petryszak R, Kersey PJ, Jaiswal P, Ware D. Gramene 2016: comparative plant genomics and pathway resources. Nucleic Acids Res 2015; 44:D1133-40. [PMID: 26553803 PMCID: PMC4702844 DOI: 10.1093/nar/gkv1179] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 10/13/2015] [Indexed: 12/21/2022] Open
Abstract
Gramene (http://www.gramene.org) is an online resource for comparative functional genomics in crops and model plant species. Its two main frameworks are genomes (collaboration with Ensembl Plants) and pathways (The Plant Reactome and archival BioCyc databases). Since our last NAR update, the database website adopted a new Drupal management platform. The genomes section features 39 fully assembled reference genomes that are integrated using ontology-based annotation and comparative analyses, and accessed through both visual and programmatic interfaces. Additional community data, such as genetic variation, expression and methylation, are also mapped for a subset of genomes. The Plant Reactome pathway portal (http://plantreactome.gramene.org) provides a reference resource for analyzing plant metabolic and regulatory pathways. In addition to ∼ 200 curated rice reference pathways, the portal hosts gene homology-based pathway projections for 33 plant species. Both the genome and pathway browsers interface with the EMBL-EBI's Expression Atlas to enable the projection of baseline and differential expression data from curated expression studies in plants. Gramene's archive website (http://archive.gramene.org) continues to provide previously reported resources on comparative maps, markers and QTL. To further aid our users, we have also introduced a live monthly educational webinar series and a Gramene YouTube channel carrying video tutorials.
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79
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Olson A, Halloran E, Romani C. Target/error overlap in jargonaphasia: The case for a one-source model, lexical and non-lexical summation, and the special status of correct responses. Cortex 2015; 73:158-79. [PMID: 26410740 DOI: 10.1016/j.cortex.2015.06.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 08/25/2013] [Accepted: 06/03/2015] [Indexed: 11/15/2022]
Abstract
We present three jargonaphasic patients who made phonological errors in naming, repetition and reading. We analyse target/response overlap using statistical models to answer three questions: 1) Is there a single phonological source for errors or two sources, one for target-related errors and a separate source for abstruse errors? 2) Can correct responses be predicted by the same distribution used to predict errors or do they show a completion boost (CB)? 3) Is non-lexical and lexical information summed during reading and repetition? The answers were clear. 1) Abstruse errors did not require a separate distribution created by failure to access word forms. Abstruse and target-related errors were the endpoints of a single overlap distribution. 2) Correct responses required a special factor, e.g., a CB or lexical/phonological feedback, to preserve their integrity. 3) Reading and repetition required separate lexical and non-lexical contributions that were combined at output.
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80
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Zuchero J, Fu MM, Sloan S, Ibrahim A, Olson A, Zaremba A, Dugas J, Wienbar S, Caprariello A, Kantor C, Leonoudakis D, Lariosa-Willingham K, Kronenberg G, Gertz K, Soderling S, Miller R, Barres B. CNS Myelin Wrapping Is Driven by Actin Disassembly. Dev Cell 2015. [DOI: 10.1016/j.devcel.2015.08.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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81
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Regan J, Adatya S, Olson A, Schnobrich D. POCUS as a Tool to Estimate PCWP. J Card Fail 2015. [DOI: 10.1016/j.cardfail.2015.06.093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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82
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Zuchero JB, Fu MM, Sloan SA, Ibrahim A, Olson A, Zaremba A, Dugas JC, Wienbar S, Caprariello AV, Kantor C, Leonoudakis D, Leonoudakus D, Lariosa-Willingham K, Kronenberg G, Gertz K, Soderling SH, Miller RH, Barres BA. CNS myelin wrapping is driven by actin disassembly. Dev Cell 2015; 34:152-67. [PMID: 26166300 PMCID: PMC4519368 DOI: 10.1016/j.devcel.2015.06.011] [Citation(s) in RCA: 215] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Revised: 05/18/2015] [Accepted: 06/11/2015] [Indexed: 12/15/2022]
Abstract
Myelin is essential in vertebrates for the rapid propagation of action potentials, but the molecular mechanisms driving its formation remain largely unknown. Here we show that the initial stage of process extension and axon ensheathment by oligodendrocytes requires dynamic actin filament assembly by the Arp2/3 complex. Unexpectedly, subsequent myelin wrapping coincides with the upregulation of actin disassembly proteins and rapid disassembly of the oligodendrocyte actin cytoskeleton and does not require Arp2/3. Inducing loss of actin filaments drives oligodendrocyte membrane spreading and myelin wrapping in vivo, and the actin disassembly factor gelsolin is required for normal wrapping. We show that myelin basic protein, a protein essential for CNS myelin wrapping whose role has been unclear, is required for actin disassembly, and its loss phenocopies loss of actin disassembly proteins. Together, these findings provide insight into the molecular mechanism of myelin wrapping and identify it as an actin-independent form of mammalian cell motility.
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83
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Holton R, Patel R, Eggebrecht M, Von Hoff B, Garrison O, McHale S, Bednar J, Olson A. Rounding on Rounds. Am J Med Qual 2015; 30:493. [DOI: 10.1177/1062860615596388] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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84
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Sathnur N, Langland J, Picel K, Olson A. Exercise Vital Sign Is Positively Associated With Cardiorespiratory Fitness In A Random State Fair Population. Med Sci Sports Exerc 2015. [DOI: 10.1249/01.mss.0000476741.59266.f9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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85
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Sackett K, Cunderlik M, Sahni N, Olson A. 58: Hyperferritinemia: Most Common Causes Revisited. Am J Clin Pathol 2015. [DOI: 10.1093/ajcp/143.suppl1.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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86
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Bloomfield HE, Olson A, Wilt TJ. Screening pelvic examinations in asymptomatic, average-risk adult women. Ann Intern Med 2014; 161:924-5. [PMID: 25506863 DOI: 10.7326/l14-5034-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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87
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Hopkins T, Solomon L, Shi Y, Rodriguez L, Donawho C, DiGiammarino E, Panchal S, Olson A, Stolarik D, Osterling D, Gao W, Johnson E, Maag D. 246 PARP inhibitors trap PARP1 onto damaged DNA via catalytic inhibition and not by an allosteric mechanism. Eur J Cancer 2014. [DOI: 10.1016/s0959-8049(14)70372-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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88
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Romani C, Tsouknida E, Olson A. Encoding order and developmental dyslexia: a family of skills predicting different orthographic components. Q J Exp Psychol (Hove) 2014; 68:99-128. [PMID: 25246235 PMCID: PMC4409052 DOI: 10.1080/17470218.2014.938666] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
We investigated order encoding in developmental dyslexia using a task that presented nonalphanumeric visual characters either simultaneously or sequentially--to tap spatial and temporal order encoding, respectively--and asked participants to reproduce their order. Dyslexic participants performed poorly in the sequential condition, but normally in the simultaneous condition, except for positions most susceptible to interference. These results are novel in demonstrating a selective difficulty with temporal order encoding in a dyslexic group. We also tested the associations between our order reconstruction tasks and: (a) lexical learning and phonological tasks; and (b) different reading and spelling tasks. Correlations were extensive when the whole group of participants was considered together. When dyslexics and controls were considered separately, different patterns of association emerged between orthographic tasks on the one side and tasks tapping order encoding, phonological processing, and written learning on the other. These results indicate that different skills support different aspects of orthographic processing and are impaired to different degrees in individuals with dyslexia. Therefore, developmental dyslexia is not caused by a single impairment, but by a family of deficits loosely related to difficulties with order. Understanding the contribution of these different deficits will be crucial to deepen our understanding of this disorder.
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89
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Wang H, Proctor CR, Edwards MA, Pryor M, Santo Domingo JW, Ryu H, Camper AK, Olson A, Pruden A. Microbial community response to chlorine conversion in a chloraminated drinking water distribution system. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:10624-10633. [PMID: 25118569 DOI: 10.1021/es502646d] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Temporary conversion to chlorine (i.e., "chlorine burn") is a common approach to controlling nitrification in chloraminated drinking water distribution systems, yet its effectiveness and mode(s) of action are not fully understood. This study characterized occurrence of nitrifying populations before, during and after a chlorine burn at 46 sites in a chloraminated distribution system with varying pipe materials and levels of observed nitrification. Quantitative polymerase chain reaction analysis of gene markers present in nitrifying populations indicated higher frequency of detection of ammonia oxidizing bacteria (AOB) (72% of samples) relative to ammonia oxidizing archaea (AOA) (28% of samples). Nitrospira nitrite oxidizing bacteria (NOB) were detected at 45% of samples, while presence of Nitrobacter NOB could not be confirmed at any of the samples. During the chlorine burn, the numbers of AOA, AOB, and Nitrospira greatly reduced (i.e., 0.8-2.4 log). However, rapid and continued regrowth of AOB and Nitrospira were observed along with nitrite production in the bulk water within four months after the chlorine burn, and nitrification outbreaks appeared to worsen 6-12 months later, even after adopting a twice annual burn program. Although high throughput sequencing of 16S rRNA genes revealed a distinct community shift and higher diversity index during the chlorine burn, it steadily returned towards a condition more similar to pre-burn than burn stage. Significant factors associated with nitrifier and microbial community composition included water age and sampling location type, but not pipe material. Overall, these results indicate that there is limited long-term effect of chlorine burns on nitrifying populations and the broader microbial community.
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90
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Bloomfield HE, Olson A, Greer N, Cantor A, MacDonald R, Rutks I, Wilt TJ. Screening pelvic examinations in asymptomatic, average-risk adult women: an evidence report for a clinical practice guideline from the American College of Physicians. Ann Intern Med 2014; 161:46-53. [PMID: 24979449 DOI: 10.7326/m13-2881] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Pelvic examination is often included in well-woman visits even when cervical cancer screening is not required. PURPOSE To evaluate the diagnostic accuracy, benefits, and harms of pelvic examination in asymptomatic, nonpregnant, average-risk adult women. Cervical cancer screening was not included. DATA SOURCES MEDLINE and Cochrane databases through January 2014 and reference lists from identified studies. STUDY SELECTION 52 English-language studies, 32 of which included primary data. DATA EXTRACTION Data were extracted on study and sample characteristics, interventions, and outcomes. Quality of the diagnostic accuracy studies was evaluated using a published instrument, and quality of the survey studies was evaluated with metrics assessing population representativeness, instrument development, and response rates. DATA SYNTHESIS The positive predictive value of pelvic examination for detecting ovarian cancer was less than 4% in the 2 studies that reported this metric. No studies that investigated the morbidity or mortality benefits of screening pelvic examination for any condition were identified. The percentage of women reporting pelvic examination-related pain or discomfort ranged from 11% to 60% (median, 35%; 8 studies [n = 4576]). Corresponding figures for fear, embarrassment, or anxiety ranged from 10% to 80% (median, 34%; 7 studies [n = 10 702]). LIMITATION Only English-language publications were included; the evidence on diagnostic accuracy, morbidity, and mortality was scant; and the studies reporting harms were generally low quality. CONCLUSION No data supporting the use of pelvic examination in asymptomatic, average-risk women were found. Low-quality data suggest that pelvic examinations may cause pain, discomfort, fear, anxiety, or embarrassment in about 30% of women. PRIMARY FUNDING SOURCE Department of Veterans Affairs.
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91
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Van't Hof JR, Oldenburg N, Duval S, Dronca S, Olson A, Peterson K, Leupker RV, Miller K, Hirsch AT. Abstract 385: The Impact of Aspirin Primary Prevention Treatment Guidelines: Temporal Trends in Aspirin Use for Primary vs Secondary Prevention, 2005-2013. Circ Cardiovasc Qual Outcomes 2014. [DOI: 10.1161/circoutcomes.7.suppl_1.385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background:
Current national prevention guidelines recommend use of low dose aspirin (ASA) for both the primary prevention (PP) and secondary prevention (SP) of heart attack and stroke. ASA use for SP has been documented to have increased over the past decade. Since the publication of the 2009 United States Preventative Services Task Force (USPSTF) recommendations for PP ASA use, data describing the trends in PP ASA use in primary care are sparse. This study evaluates trends in PP and SP ASA use in primary care clinics from a large, regional health system over an 8 year period (2005-2013).
Methods:
A bi-annual cross-sectional electronic medical record (EMR) chart extraction was performed from 2005 to 2013 to evaluate documented ASA use for all patient encounters within primary care clinics in the Fairview Health System (Minnesota). Primary prevention candidates were defined as individuals within the USPSTF guideline age and sex target populations (men aged 45-79, and women aged 55-79 years) with no documented history of an atherosclerotic syndrome or contraindication to ASA use (aspirin allergy, peptic ulcer disease, or concurrent antithrombotic therapy). Secondary prevention candidates were defined as adults within the same age and gender range with a history of coronary artery disease, peripheral artery disease or ischemic stroke. The ASA treatment to candidacy ratio was calculated for the PP and SP populations.
Results:
Over 225,000 unique encounters at 66 primary care clinics were analyzed over the 8 year study period. The PP population was younger (60.4±8.7 vs. 66.2±8.3 years), with lower prevalence of hypertension (49 vs. 79%), hyperlipidemia (54 vs. 84%), and diabetes (17 vs. 35%) compared to the SP cohort. The mean SP ASA use of 86% was high, concordant with national trends, and did not change over this period. In contrast, PP ASA average use was 44% with no increase after publication of the 2009 USPSTF guideline. Documented contraindications to ASA use were uncommon (ASA allergy, 2.1 and 2.8%; peptic ulcer disease, 3.2 and 7.2%; and use of other antithrombotic medications, 4.6 and 32.6% in PP and SP populations respectively).
Conclusion:
Secondary prevention ASA use in primary care settings remains high, but ASA use for primary prevention of cardiovascular events is low. Despite creation of national guidelines, aspirin use in the PP population is half the rate of ASA use for secondary prevention. Additional methods to safely and effectively disseminate this primary prevention aspirin use recommendation, targeting both the public and health care providers, are warranted.
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92
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Harris L, Olson A, Humphreys G. The link between STM and sentence comprehension: A neuropsychological rehabilitation study. Neuropsychol Rehabil 2014; 24:678-720. [DOI: 10.1080/09602011.2014.892885] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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93
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Bormann T, Romani C, Olson A, Wallesch CW. Morphological-compound dysgraphia in an aphasic patient: "A wild write through the lexicon". Cogn Neuropsychol 2014; 31:75-105. [PMID: 24517220 DOI: 10.1080/02643294.2013.877879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We describe the case of a dysgraphic aphasic individual--S.G.W.--who, in writing to dictation, produced high rates of formally related errors consisting of both lexical substitutions and what we call morphological-compound errors involving legal or illegal combinations of morphemes. These errors were produced in the context of a minimal number of semantic errors. We could exclude problems with phonological discrimination and phonological short-term memory. We also excluded rapid decay of lexical information and/or weak activation of word forms and letter representations since S.G.W.'s spelling showed no effect of delay and no consistent length effects, but, instead, paradoxical complexity effects with segmental, lexical, and morphological errors that were more complex than the target. The case of S.G.W. strongly resembles that of another dysgraphic individual reported in the literature--D.W.--suggesting that this pattern of errors can be replicated across patients. In particular, both patients show unusual errors resulting in the production of neologistic compounds (e.g., "bed button" in response to "bed"). These patterns can be explained if we accept two claims: (a) Brain damage can produce both a reduction and an increase in lexical activation; and (b) there are direct connections between phonological and orthographic lexical representations (a third spelling route). We suggest that both patients are suffering from a difficulty of lexical selection resulting from excessive activation of formally related lexical representations. This hypothesis is strongly supported by S.G.W.'s worse performance in spelling to dictation than in written naming, which shows that a phonological input, activating a cohort of formally related lexical representations, increases selection difficulties.
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Hiu T, Bliss T, Manley N, Wang E, Nishiyama Y, Sun G, Olson A, Micheva K, Wang G, Berry J, Smith S, Steinberg G. Abstract 14: Synaptic Remodeling after Stroke Enhanced by Transplanted Human Neural Stem Cells is Coincident with Functional Recovery. Stroke 2014. [DOI: 10.1161/str.45.suppl_1.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background:
Stem cell transplantation (Tx) has emerged as a promising new experimental treatment for stroke; understanding its mechanism of action will facilitate the translation of stem cell therapy to the clinic. The ultimate change in brain plasticity is manifested at the synaptic level, however, the synaptic remodeling after stem cell therapy remains unknown. Here we evaluate the effect of transplanted human neural progenitor cells (hNPCs) on the peri-infarct synaptic remodeling in the post-ischemic brain.
Materials and Methods:
We use array tomography, a high-resolution proteomic imaging method, to determine how hNPCs affect the number and subtype of glutamate and GABA synapses after stroke. Vehicle or hNPCs were transplanted into the ischemic cortex of Nude rats 7 days after distal middle cerebral artery occlusion. Neurological recovery was assessed weekly using a battery of behavioral tests. The arrays of serial ultrathin sections (70 nm), removed from the peri-infarct cortex at 1 and 4 weeks post-Tx, were stained using multiple synaptic markers and imaged in cortical layer 2/3 and 5. Computational analysis of the resultant staining pattern was used to identify and quantify subtypes of glutamate and GABA synapses.
Results:
Tx of hNPCs significantly improved behavioral recovery after stroke compared to vehicle-treated rats (4 weeks post-transplantation; p<0.01) without altering the infarct size. hNPC-treated rats had a higher density of VGluT1-containing glutamate synapses (0.223 vs 0.185 synapses/μm3, p<0.05), and GluA2-containing glutamate synapses (0.091 vs 0.069 synapses/μm3, p<0.05) in layer 5 at 4 weeks post-Tx, compared to vehicle-treated rats. However, hNPCs had did not alter total number of glutamate synapses. This synaptic increase was cortical layer-specific observed in layer 5 but not .in layer 2/3. hNPCs had no detectable effect on the density of GABA synapses in either layer 5 or 2/3 at 1 week or 4 weeks post-Tx.
Conclusions:
These results provide novel new information about the organization of synaptic circuitry and its plasticity after stem cell therapy. These data suggest that stem cells alter the subunit composition of glutamate synapses after stroke and this is coincident with stem cell-induced functional recovery.
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95
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Hiu T, Bliss T, Paz J, Wang E, Farzampour Z, Olson A, Micheva K, Wang G, Tran K, Manley N, Lemmens R, Nishiyama Y, Arac A, Hamilton S, O’Rourke N, Smith S, Huguenard J, Steinberg G. Abstract W MP41: Potentiation of Gaba-Mediated Synaptic Inhibition in the Recovery Phase: A Novel Therapeutic Target for Stroke. Stroke 2014. [DOI: 10.1161/str.45.suppl_1.wmp41] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background:
Stroke is a major cause of disability yet pharmacotherapy targeting the recovery phase is lacking. Cortical circuit reorganization adjacent to the stroke site promotes recovery, thus elucidating mechanisms that promote this plasticity could lead to new therapeutics.
Tonic
neuronal inhibition, mediated by extrasynaptic GABA
A
receptors,inhibits post-stroke recovery. However, effects of
phasic
(synaptic) GABA signaling - which promotes plasticity during development - are unknown. Here we use a combined approach of i) array tomography to determine the composition of GABA synapses in the post-stroke mouse brain, ii) electrophysiology to determine whether stroke leads to functional changes in GABA-mediated phasic inhibition, and (iii) treatment with zolpidem, an FDA-approved GABA agonist, to modulate recovery.
Results:
We found, using array tomography, a 1.7-fold increase in the number of GABAergic synapses containing the α1 receptor subunit in layer 5 of the peri-infarct cortex (synapse number/μm
3
: 0.039±0.006 (control) vs 0.064±0.006 (stroke); P<0.01), but not in layer 2/3. There was an associated increase in spontaneous inhibitory post-synaptic currents (sIPSC) specific to layer 5 pyramidal neurons (sIPSC charge (fC): -403±27.8 (control) vs -724±166 (stroke); p=0.03). This effect was transient, occurring during the onset of functional recovery. To test whether the increased phasic inhibitory GABAergic signaling promotes stroke recovery, we treated animals with zolpidem, an agonist with high affinity for α1 subunit-containing GABA
A
receptors. Low dose zolpidem increased GABA
A
phasic signaling in layer 5 pyramidal cells and notably increased the rate and extent of behavioral recovery without altering infarct size.
Conclusions:
These data provide the first evidence that enhanced GABA
A
-mediated synaptic activity during the recovery phase improves stroke outcome. These data identify modulation of phasic GABA signaling as a novel therapeutic strategy for stroke, indicate zolpidem as a potential drug to improve recovery, and underscore the necessity to distinguish the role of tonic and phasic GABA inhibition in stroke recovery.
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Van der Nest MA, Olson A, Lind M, Vélëz H, Dalman K, Brandström Durling M, Karlsson M, Stenlid J. Distribution and evolution of het gene homologs in the basidiomycota. Fungal Genet Biol 2013; 64:45-57. [PMID: 24380733 DOI: 10.1016/j.fgb.2013.12.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 12/04/2013] [Accepted: 12/20/2013] [Indexed: 12/24/2022]
Abstract
In filamentous fungi a system known as somatic incompatibility (SI) governs self/non-self recognition. SI is controlled by a regulatory signaling network involving proteins encoded at the het (heterokaryon incompatible) loci. Despite the wide occurrence of SI, the molecular identity and structure of only a small number of het genes and their products have been characterized in the model fungi Neurospora crassa and Podospora anserina. Our aim was to identify and study the distribution and evolution of putative het gene homologs in the Basidiomycota. For this purpose we used the information available for the model fungi to identify homologs of het genes in other fungi, especially the Basidiomycota. Putative het-c, het-c2 and un-24 homologs, as well as sequences containing the NACHT, HET or WD40 domains present in the het-e, het-r, het-6 and het-d genes were identified in certain members of the Ascomycota and Basidiomycota. The widespread phylogenetic distribution of certain het genes may reflect the fact that the encoded proteins are involved in fundamental cellular processes other than SI. Although homologs of het-S were previously known only from the Sordariomycetes (Ascomycota), we also identified a putative homolog of this gene in Gymnopus luxurians (Basidiomycota, class Agaricomycetes). Furthermore, with the exception of un-24, all of the putative het genes identified occurred mostly in a multi-copy fashion, some with lineage and species-specific expansions. Overall our results indicated that gene duplication followed by gene loss and/or gene family expansion, as well as multiple events of domain fusion and shuffling played an important role in the evolution of het gene homologs of Basidiomycota and other filamentous fungi.
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97
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Eveland AL, Goldshmidt A, Pautler M, Morohashi K, Liseron-Monfils C, Lewis MW, Kumari S, Hiraga S, Yang F, Unger-Wallace E, Olson A, Hake S, Vollbrecht E, Grotewold E, Ware D, Jackson D. Regulatory modules controlling maize inflorescence architecture. Genome Res 2013; 24:431-43. [PMID: 24307553 PMCID: PMC3941108 DOI: 10.1101/gr.166397.113] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Genetic control of branching is a primary determinant of yield, regulating seed number and harvesting ability, yet little is known about the molecular networks that shape grain-bearing inflorescences of cereal crops. Here, we used the maize (Zea mays) inflorescence to investigate gene networks that modulate determinacy, specifically the decision to allow branch growth. We characterized developmental transitions by associating spatiotemporal expression profiles with morphological changes resulting from genetic perturbations that disrupt steps in a pathway controlling branching. Developmental dynamics of genes targeted in vivo by the transcription factor RAMOSA1, a key regulator of determinacy, revealed potential mechanisms for repressing branches in distinct stem cell populations, including interactions with KNOTTED1, a master regulator of stem cell maintenance. Our results uncover discrete developmental modules that function in determining grass-specific morphology and provide a basis for targeted crop improvement and translation to other cereal crops with comparable inflorescence architectures.
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98
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Harris L, Olson A, Humphreys G. Type-specific proactive interference in patients with semantic and phonological STM deficits. Memory 2013; 22:972-89. [PMID: 24295224 DOI: 10.1080/09658211.2013.860171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Prior neuropsychological evidence suggests that semantic and phonological components of short-term memory (STM) are functionally and neurologically distinct. The current paper examines proactive interference (PI) from semantic and phonological information in two STM-impaired patients, DS (semantic STM deficit) and AK (phonological STM deficit). In Experiment 1 probe recognition tasks with open and closed sets of stimuli were used. Phonological PI was assessed using nonword items, and semantic and phonological PI was assessed using words. In Experiment 2 phonological and semantic PI was elicited by an item recognition probe test with stimuli that bore phonological and semantic relations to the probes. The data suggested heightened phonological PI for the semantic STM patient, and exaggerated effects of semantic PI in the phonological STM case. The findings are consistent with an account of extremely rapid decay of activated type-specific representations in cases of severely impaired phonological and semantic STM.
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99
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Monaco MK, Stein J, Naithani S, Wei S, Dharmawardhana P, Kumari S, Amarasinghe V, Youens-Clark K, Thomason J, Preece J, Pasternak S, Olson A, Jiao Y, Lu Z, Bolser D, Kerhornou A, Staines D, Walts B, Wu G, D'Eustachio P, Haw R, Croft D, Kersey PJ, Stein L, Jaiswal P, Ware D. Gramene 2013: comparative plant genomics resources. Nucleic Acids Res 2013; 42:D1193-9. [PMID: 24217918 PMCID: PMC3964986 DOI: 10.1093/nar/gkt1110] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Gramene (http://www.gramene.org) is a curated online resource for comparative functional genomics in crops and model plant species, currently hosting 27 fully and 10 partially sequenced reference genomes in its build number 38. Its strength derives from the application of a phylogenetic framework for genome comparison and the use of ontologies to integrate structural and functional annotation data. Whole-genome alignments complemented by phylogenetic gene family trees help infer syntenic and orthologous relationships. Genetic variation data, sequences and genome mappings available for 10 species, including Arabidopsis, rice and maize, help infer putative variant effects on genes and transcripts. The pathways section also hosts 10 species-specific metabolic pathways databases developed in-house or by our collaborators using Pathway Tools software, which facilitates searches for pathway, reaction and metabolite annotations, and allows analyses of user-defined expression datasets. Recently, we released a Plant Reactome portal featuring 133 curated rice pathways. This portal will be expanded for Arabidopsis, maize and other plant species. We continue to provide genetic and QTL maps and marker datasets developed by crop researchers. The project provides a unique community platform to support scientific research in plant genomics including studies in evolution, genetics, plant breeding, molecular biology, biochemistry and systems biology.
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100
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Olson A. Mobile mammography: driving preventive care for underserved women. N C Med J 2013; 74:542-543. [PMID: 24316787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
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