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Background: In our previous investigations of the role of the extracellular matrix (ECM) in promoting neurite growth we have observed that a permissive laminin (LN) substrate stimulates differential growth responses in subpopulations of mature dorsal root ganglion (DRG) neurons. DRG neurons expressing Trk and p75 receptors grow neurites on a LN substrate in the absence of neurotrophins, while isolectin B4-binding neurons (IB4+) do not display significant growth under the same conditions. We set out to determine whether there was an expression signature of the LN-induced neurite growth phenotype. Using a lectin binding protocol IB4+ neurons were isolated from dissociated DRG neurons, creating two groups - IB4+ and IB4-. A small-scale microarray approach was employed to screen the expression of a panel of ECM-associated genes following dissociation (t=0) and after 24 hr culture on LN (t=24LN). This was followed by qRT-PCR and immunocytochemistry of selected genes. Results: The microarray screen showed that 36 of the 144 genes on the arrays were consistently expressed by the neurons. The array analyses showed that six genes had lower expression in the IB4+ neurons compared to the IB4- cells at t=0 (CTSH, Icam1, Itgβ1, Lamb1, Plat, Spp1), and one gene was expressed at higher levels in the IB4+ cells (Plaur). qRT-PCR was carried out as an independent assessment of the array results. There were discrepancies between the two methods, with qRT-PCR confirming the differences in Lamb1, Plat and Plaur, and showing decreased expression of AdamTs1, FN, and Icam in the IB4+ cells at t=0. After 24 hr culture on LN, there were no significant differences detected by qRT-PCR between the IB4+ and IB4- cells. However, both groups showed upregulation of Itgβ1 and Plaur after 24 hr on LN, the IB4+ group also had increased Plat, and the IB4- cells showed decreased Lamb1, Icam1 and AdamTs1. Further, the array screen also detected a number of genes (not subjected to qRT-PCR) expressed similarly by both populations in relatively high levels but not detectably influenced by time in culture (Bsg, Cst3, Ctsb, Ctsd, Ctsl, Mmp14, Mmp19, Sparc. We carried out immunohistochemistry to confirm expression of proteins encoded by a number of these genes. Conclusions:Our results show that 1B4+ and IB4- neurons differ in the expression of several genes that are associated with responsiveness to the ECM prior to culturing (AdamTs1, FN, Icam1, Lamb1, Plat, Plaur). The data suggest that the genes expressed at higher levels in the IB4- neurons could contribute to the initial growth response of these cells in a permissive environment and could also represent a common injury response that subsequently promotes axon regeneration. The differential expression of several extracellular matrix molecules (FN, Lamb1, Icam) may suggest that the IB4- neurons are capable of maintaining /secreting their local extracellular environment which could aid in the regenerative process. Overall, these data provide new information on potential targets that could be manipulated to enhance axonal regeneration in the mature nervous system.

Objective: To generate a national multiple sclerosis (MS) prevalence estimate for the United States by applying a validated algorithm to multiple administrative health claims (AHC) datasets. Methods: A validated algorithm was applied to private, military, and public AHC datasets to identify adult cases of MS between 2008 and 2010. In each dataset, we determined the 3-year cumulative prevalence overall and stratified by age, sex, and census region. We applied insurance-specific and stratum-specific estimates to the 2010 US Census data and pooled the findings to calculate the 2010 prevalence of MS in the United States cumulated over 3 years. We also estimated the 2010 prevalence cumulated over 10 years using 2 models and extrapolated our estimate to 2017. Results: The estimated 2010 prevalence of MS in the US adult population cumulated over 10 years was 309.2 per 100,000 (95% confidence interval [CI] 308.1–310.1), representing 727,344 cases. During the same time period, the MS prevalence was 450.1 per 100,000 (95% CI 448.1–451.6) for women and 159.7 (95% CI 158.7–160.6) for men (female:male ratio 2.8). The estimated 2010 prevalence of MS was highest in the 55- to 64-year age group. A US north-south decreasing prevalence gradient was identified. The estimated MS prevalence is also presented for 2017. Conclusion: The estimated US national MS prevalence for 2010 is the highest reported to date and provides evidence that the north-south gradient persists. Our rigorous algorithm-based approach to estimating prevalence is efficient and has the potential to be used for other chronic neurologic conditions. Prev of MS in the US-E-Appendix-Feb-19-2018

Collections of cells called engrams are thought to represent memories. Although there has been progress in identifying and manipulating single engrams, little is known about how multiple engrams interact to influence memory. In lateral amygdala (LA), neurons with increased excitability during training outcompete their neighbors for allocation to an engram. We examined whether competition based on neuronal excitability also governs the interaction between engrams. Mice received two distinct fear conditioning events separated by different intervals. LA neuron excitability was optogenetically manipulated and revealed a transient competitive process that integrates memories for events occurring closely in time (coallocating overlapping populations of neurons to both engrams) and separates memories for events occurring at distal times (disallocating nonoverlapping populations to each engram). Rashid et al Science 2016- Data for Figs 1-4, S1-S9Excel file with all data presented in manuscript (each sheet corresponds to specific figures as indicated).Rashid et al Science 2016.xlsx

OBJECTIVE. To assess whether HS severity is mirrored at the level of large-scale networks. METHODS. We studied preoperative high-resolution anatomical and diffusion-weighted MRI of 44 TLE patients with histopathological diagnosis of HS (n=25; TLE-HS) and isolated gliosis (n=19; TLE-G), and 25 healthy controls. Hippocampal measurements included surface-based subfield mapping of atrophy and T2 hyperintensity indexing cell loss and gliosis, respectively. Whole-brain connectomes were generated via diffusion tractography and examined using graph theory along with a novel network control theory paradigm which simulates functional dynamics from structural network data. RESULTS. Compared to controls, we observed markedly increased path length and decreased clustering in TLE-HS compared to controls, indicating lower global and local network efficiency, while TLE-G showed only subtle alterations. Similarly, network controllability was lower in TLE-HS only, suggesting limited range of functional dynamics. Hippocampal imaging markers were positively associated with macroscale network alterations, particularly in ipsilateral CA1-3. Systematic assessment across several networks revealed maximal changes in the hippocampal circuity. Findings were consistent when correcting for cortical thickness, suggesting independence from grey matter atrophy. CONCLUSIONS. Severe HS is associated with marked remodeling of connectome topology and structurally-governed functional dynamics in TLE, as opposed to isolated gliosis which has negligible effects. Cell loss, particularly in CA1-3, may exert a cascading effect on brain-wide connectomes, underlining coupled disease processes across multiple scales. Data_phen_conn_dryadPhenotypic information and mean connectome feature data for Bernhardt et al. (2019) Temporal lobe epilepsy: hippocampal pathology modulates white matter connectome topology and controllability. Neurology

Premise of the study: Polyploidization is a common and recurring phenomenon in plants and is often thought to be a mechanism of "instant speciation." Whether polyploidization is associated with the formation of new species ("cladogenesis") or simply occurs over time within a lineage ("anagenesis") has never, however, been assessed systematically. Methods: Here, we tested this hypothesis using phylogenetic and karyotypic information from 235 plant genera (mostly angiosperms). We first constructed a large database of combined sequence and chromosome number data sets using an automated procedure. We then applied likelihood models (ClaSSE) that estimate the degree of synchronization between polyploidization and speciation events in maximum likelihood and Bayesian frameworks. Key results: Our maximum likelihood analysis indicated that 35 genera supported a model that includes cladogenetic transitions over a model with only anagenetic transitions, whereas three genera supported a model that incorporates anagenetic transitions over one with only cladogenetic transitions. Furthermore, the Bayesian analysis supported a preponderance of cladogenetic change in four genera but did not support a preponderance of anagenetic change in any genus. Conclusions: Overall, these phylogenetic analyses provide the first broad confirmation that polyploidization is temporally associated with speciation events, suggesting that it is indeed a major speciation mechanism in plants, at least in some genera. PloiDBPhylogenetic trees inferred using MrBayes, ploidy estimates using ChromEvol, and TPL-based genus species diversity estimates for 223 genera.ploidb_dryad.tar.gz

Funding: This work was supported by CIHR Foundation grant FDN 143312 (DWA), CIHR grant PJT 156167 (LZP), the European Union's Seventh Framework Programme (FP7/2008–2013) under Grant Agreement 627951 (Marie Curie IOF to PM), the German Academic Exchange Service (DAAD) with funds from the German Federal Ministry of Education and Research (57212163 to PM), and in part by the Bundesministerium für Bildung und Forschung, Germany (BMBF, grant no. 16GW0191 to PM). JMP is recipient of the Queen Elizabeth II graduate scholarship in science and technology. PM has been supported by the BIH‐Charité Clinical Scientist Program funded by the Charité – Universitätsmedizin Berlin and the Berlin Institute of Health. DWA holds a Tier 1 Canada Research Chair (CRC) in Membrane Biogenesis. LZP holds a Tier 1 CRC in Molecular Oncology. 3D confocal image stacks of primary cortical neurons under different treatment conditions to test the functionality of Phindr3D. Explanatory .txt file contained in the ZIP file. Please see the manuscript for details and on how to access the full data set: Rapid 3D phenotypic analysis of neurons and organoids using data-driven cell segmentation-free machine learning Philipp Mergenthaler*, Santosh Hariharan*, James M. Pemberton, Corey Lourenco, Linda Z. Penn, David W. Andrews PLOS Computational Biology, DOI: 10.1371/journal.pcbi.1008630 Phindr3D is available on GitHub: GitHub - DWALab/Phindr3D

Assemblies of vertically connected neurons in the cerebral cortex form information processing units (columns) that participate in the distribution and segregation of sensory signals. Despite well-accepted models of columnar architecture, functional mechanisms of inter-laminar communication remain poorly understood. Hence, the purpose of the present investigation was to examine the effects of sensory information features on columnar response properties. Using acute recording techniques, extracellular response activity was collected from the right hemisphere of eight mature cats (felis catus). Recordings were conducted with multichannel electrodes that permitted the simultaneous acquisition of neuronal activity within primary auditory cortex columns. Neuronal responses to simple (pure tones), complex (noise burst and frequency modulated sweeps), and ecologically relevant (con-specific vocalizations) acoustic signals were measured. Collectively, the present investigation demonstrates that despite consistencies in neuronal tuning (characteristic frequency), irregularities in discharge activity between neurons of individual A1 columns increase as a function of spectral (signal complexity) and temporal (duration) acoustic variations. Multi-unit responses to acoustic signals within A1 columnsThe data set consists of eight multi-unit electrophysiology experiments located within a single .zip file. Acoustic feature (signal type and duration) are in subfolders where data rasters for each recording session conducted can be found. Columns represent time and rows trial number. Data is presented as Matlab files.DRYAD.zip

Background: Clinical trials that end prematurely (or “terminate”) raise financial, ethical, and scientific concerns. The extent to which the results of such trials are disseminated and the reasons for termination have not been well characterized. Methods and Findings: A cross-sectional, descriptive study of terminated clinical trials posted on the ClinicalTrials.gov results database as of February 2013 was conducted. The main outcomes were to characterize the availability of primary outcome data on ClinicalTrials.gov and in the published literature and to identify the reasons for trial termination. Approximately 12% of trials with results posted on the ClinicalTrials.gov results database (905/7,646) were terminated. Most trials were terminated for reasons other than accumulated data from the trial (68%; 619/905), with an insufficient rate of accrual being the lead reason for termination among these trials (57%; 350/619). Of the remaining trials, 21% (193/905) were terminated based on data from the trial (findings of efficacy or toxicity) and 10% (93/905) did not specify a reason. Overall, data for a primary outcome measure were available on ClinicalTrials.gov and in the published literature for 72% (648/905) and 22% (198/905) of trials, respectively. Primary outcome data were reported on the ClinicalTrials.gov results database and in the published literature more frequently (91% and 46%, respectively) when the decision to terminate was based on data from the trial. Conclusions: Trials terminate for a variety of reasons, not all of which reflect failures in the process or an inability to achieve the intended goals. Primary outcome data were reported most often when termination was based on data from the trial. Further research is needed to identify best practices for disseminating the experience and data resulting from terminated trials in order to help ensure maximal societal benefit from the investments of trial participants and others involved with the study. DATA_Terminated Trials in ClinicalTrialsgov Results Database (19 Feb 2013)CSV data file containing data retrieved from the ClinicalTrials.gov registry and results database on February 19, 2013. Additional details are available in the ReadMe file.

We carried out an admixture mapping study of lipid traits in two samples from Mexico City. Native American locus ancestry was significantly associated with triglyceride levels in a broad region of chromosome 11 overlapping the BUD13, ZNF259 and APOA5 genes. In our fine-mapping analysis of this region using dense genome-wide data, rs964184 is the only marker included in the 99% credible set of SNPs, providing strong support for rs964184 as the causal variant within this region. The frequency of the allele associated with increased triglyceride concentrations (rs964184-G) is between 30-40% higher in Native American populations from Mexico than in European populations. The evidence currently available for this variant indicates that it may be exerting its effect through three potential mechanisms: 1) modification of enhancer activity, 2) regulation of the expression of several genes in cis and/or trans, or 3) modification of the methylation patterns of the promoter of the APOA5 gene. MC-sample1-HDL-AMAdmixture Mapping results for HDL-cholesterol: Mexico City sample 1MC-sample1-LDL-AMAdmixture Mapping results for LDL-cholesterol: Mexico City sample 1MC-sample1-TCHOL-AMAdmixture Mapping results for Total-cholesterol: Mexico City sample 1MC-sample1-TG-AMAdmixture Mapping results for triglycerides: Mexico City sample 1MC-sample2-HDL-AMAdmixture Mapping results for HDL-cholesterol: Mexico City sample 2MC-sample2-LDL-AMAdmixture Mapping results for LDL-cholesterol: Mexico City sample 2MC-sample2-TCHOL-AMAdmixture Mapping results for Total-cholesterol: Mexico City sample 2MC-sample2-TG-AMAdmixture Mapping results for triglycerides: Mexico City sample 2Mexico-City-AM-signalsAdmixture Mapping signals identified in both Mexico City samples for all the lipid traits.