Publications by authors named "Robert Fisher"

568 Publications

The SANTÉ study at 10 years of follow-up: Effectiveness, safety, and sudden unexpected death in epilepsy.

Epilepsia 2021 Apr 8. Epub 2021 Apr 8.

Department of Neurology, Stanford University, Stanford, California, USA.

Objective: We evaluated the efficacy and safety of deep brain anterior thalamus stimulation after 7 and 10 years, and report the incidence of sudden unexpected death in epilepsy (SUDEP) and overall mortality in adults in the Stimulation of the Anterior Nucleus of the Thalamus for Epilepsy (SANTÉ) study.

Methods: After the 3-month blinded and 9-month unblinded phases, subjects continued to be assessed during long-term follow-up (LTFU) and later a continued therapy access phase (CAP), to further characterize adverse events and the incidence of SUDEP. Stimulus parameter and medication changes were allowed.

Results: One hundred ten implanted subjects accumulated a total of 938 device-years of experience (69 subjects during the LTFU phase and 61 subjects in the CAP phase). Prior to study closure, 57 active subjects continued therapy at 14 study centers, with follow-up of at least 10 (maximum 14) years. At 7 years, median seizure frequency percent reduction from baseline was 75% (p < .001), with no outcome differences related to prior vagus nerve stimulation or resective surgery. The most severe seizure type, focal to bilateral tonic-clonic, was reduced by 71%. Adding new antiseizure medications did not impact the pattern of seizure reduction over time. There were no unanticipated serious adverse events in the study. The definite-plus-probable SUDEP rate, based on SANTÉ study experience (two deaths in 938 years) and previous pilot studies (0 deaths in 76 years), indicated a rate of 2.0 deaths for 1000 person-years. Overall mortality was 6.9 deaths per 1000 person-years.

Significance: The long-term efficacy and safety profiles of the deep brain stimulation (DBS) system for epilepsy are favorable and demonstrate stable outcomes. Improvement in frequency of the most severe seizure type may reduce SUDEP risk. The SUDEP rate with DBS (2.0) is comparable to other neuromodulation treatments (i.e., vagus nerve stimulation, responsive neurostimulation) for drug-resistant focal epilepsy.
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http://dx.doi.org/10.1111/epi.16895DOI Listing
April 2021

Salt stress enhances early symbiotic gene expression in Medicago truncatula and induces a stress-specific set of rhizobium-responsive genes.

Mol Plant Microbe Interact 2021 Apr 5. Epub 2021 Apr 5.

University of Vermont, Plant Biology, 63 Carrigan Drive, Burlington, Vermont, United States, 05405-0086;

Salt stress is a major agricultural concern inhibiting not only plant growth but also the symbiotic association between legume roots and the soil bacteria rhizobia. This symbiotic association is initiated by a molecular dialogue between the two partners, leading to the activation of a signaling cascade in the legume host and ultimately the formation of nitrogen-fixing root nodules. Here we show that a moderate salt stress increases the responsiveness of early symbiotic genes in Medicago truncatula to its symbiotic partner, Sinorhizobium meliloti, while conversely, inoculation with S. meliloti counteracts salt-regulated gene expression, restoring one-third to control levels. Our analysis of Early Nodulin 11 shows that salt-induced expression is dynamic, Nod-factor dependent, and requires the ionic, but not the osmotic, component of salt. We demonstrate that salt stimulation of rhizobium-induced gene expression requires NSP2, which functions as a node to integrate the abiotic and biotic signals. In addition, our work reveals that inoculation with Sinorhizobium meliloti succinoglycan mutants also hyperinduces ENOD11 expression in the presence or absence of salt, suggesting a possible link between rhizobial exopolysaccharide and the plant response to salt stress. Finally, we identify an accessory set of genes that are induced by rhizobium only under conditions of salt stress and have not been previously identified as being nodulation-related genes. Our data suggests that interplay of core nodulation genes with different accessory sets, specific for different abiotic conditions, function to establish the symbiosis. Together, our findings reveal a complex and dynamic interaction between plant, microbe, and environment.
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http://dx.doi.org/10.1094/MPMI-01-21-0019-RDOI Listing
April 2021

The effect of target salience and size in visual search within naturalistic scenes under degraded vision.

J Vis 2021 Apr;21(4)

School of Informatics, University of Edinburgh, UK.

We address two questions concerning eye guidance during visual search in naturalistic scenes. First, search has been described as a task in which visual salience is unimportant. Here, we revisit this question by using a letter-in-scene search task that minimizes any confounding effects that may arise from scene guidance. Second, we investigate how important the different regions of the visual field are for different subprocesses of search (target localization, verification). In Experiment 1, we manipulated both the salience (low vs. high) and the size (small vs. large) of the target letter (a "T"), and we implemented a foveal scotoma (radius: 1°) in half of the trials. In Experiment 2, observers searched for high- and low-salience targets either with full vision or with a central or peripheral scotoma (radius: 2.5°). In both experiments, we found main effects of salience with better performance for high-salience targets. In Experiment 1, search was faster for large than for small targets, and high-salience helped more for small targets. When searching with a foveal scotoma, performance was relatively unimpaired regardless of the target's salience and size. In Experiment 2, both visual-field manipulations led to search time costs, but the peripheral scotoma was much more detrimental than the central scotoma. Peripheral vision proved to be important for target localization, and central vision for target verification. Salience affected eye movement guidance to the target in both central and peripheral vision. Collectively, the results lend support for search models that incorporate salience for predicting eye-movement behavior.
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http://dx.doi.org/10.1167/jov.21.4.2DOI Listing
April 2021

Induced organoids derived from patients with ulcerative colitis recapitulate colitic reactivity.

Nat Commun 2021 01 11;12(1):262. Epub 2021 Jan 11.

Department of Cancer Biology, Cleveland Clinic Lerner Research Institute, Cleveland, OH, 44195, USA.

The pathogenesis of ulcerative colitis (UC), a major type of inflammatory bowel disease, remains unknown. No model exists that adequately recapitulates the complexity of clinical UC. Here, we take advantage of induced pluripotent stem cells (iPSCs) to develop an induced human UC-derived organoid (iHUCO) model and compared it with the induced human normal organoid model (iHNO). Notably, iHUCOs recapitulated histological and functional features of primary colitic tissues, including the absence of acidic mucus secretion and aberrant adherens junctions in the epithelial barrier both in vitro and in vivo. We demonstrate that the CXCL8/CXCR1 axis was overexpressed in iHUCO but not in iHNO. As proof-of-principle, we show that inhibition of CXCL8 receptor by the small-molecule non-competitive inhibitor repertaxin attenuated the progression of UC phenotypes in vitro and in vivo. This patient-derived organoid model, containing both epithelial and stromal compartments, will generate new insights into the underlying pathogenesis of UC while offering opportunities to tailor interventions to the individual patient.
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http://dx.doi.org/10.1038/s41467-020-20351-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7801686PMC
January 2021

The influence of species life history and distribution characteristics on species responses to habitat fragmentation in an urban landscape.

J Anim Ecol 2021 Mar 1;90(3):685-697. Epub 2021 Feb 1.

U.S. Geological Survey, Western Ecological Research Center, San Diego, CA, USA.

Fragmentation within urbanized environments often leads to a loss of native species diversity; however, variation exists in responses among-species and among-populations within species. We aimed to identify patterns in species biogeography in an urbanized landscape to understand anthropogenic effects on vertebrate communities and identify species that are more sensitive or resilient to landscape change. We investigated patterns in species richness and species responses to fragmentation in southern Californian small vertebrate communities using multispecies occupancy models and determined factors associated with overall commonness and sensitivity to patch size for 45 small vertebrate species both among and within remaining non-developed patches. In general, smaller patches had fewer species, with amphibian species richness being particularly sensitive to patch size effects. Mammals were generally more common, occurring both in a greater proportion of patches and a higher proportion of the sites within occupied patches. Alternatively, amphibians were generally restricted to larger patches but were more ubiquitous within smaller patches when occupied. Species range size was positively correlated with how common a species was across and within patches, even when controlling for only patches that fell within a species' range. We found sensitivity to patch size was greater for more fecund species and depended on where the patch occurred within a species' range. While all taxa were more likely to occur in patches in the warmer portions of their ranges, amphibians and mammals were more sensitive to fragmentation in these warmer areas as compared to the rest of their ranges. Similarly, amphibians occurred at a smaller proportion of sites within patches in drier portions of their ranges. Mammals occurred at a higher proportion of sites that were also in drier portions of their range while reptiles did not differ in their sensitivity to patch size by range position. We demonstrate that taxonomy, life history, range size and range position can predict commonness and sensitivity of species across this highly fragmented yet biodiverse landscape. The impacts of fragmentation on species communities within an urban landscape depend on scale, with differences emerging among and within species and populations.
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http://dx.doi.org/10.1111/1365-2656.13403DOI Listing
March 2021

Conservation Genomics of the Threatened Western Spadefoot, Spea hammondii, in Urbanized Southern California.

J Hered 2020 12;111(7):613-627

Department of Ecology and Evolutionary Biology, and La Kretz Center for California Conservation Science, University of California Los Angeles, Los Angeles, CA.

Populations of the western spadefoot (Spea hammondii) in southern California occur in one of the most urbanized and fragmented landscapes on the planet and have lost up to 80% of their native habitat. Orange County is one of the last strongholds for this pond-breeding amphibian in the region, and ongoing restoration efforts targeting S. hammondii have involved habitat protection and the construction of artificial breeding ponds. These efforts have successfully increased breeding activity, but genetic characterization of the populations, including estimates of effective population size and admixture between the gene pools of constructed artificial and natural ponds, has never been undertaken. Using thousands of genome-wide single-nucleotide polymorphisms, we characterized the population structure, genetic diversity, and genetic connectivity of spadefoots in Orange County to guide ongoing and future management efforts. We identified at least 2, and possibly 3 major genetic clusters, with additional substructure within clusters indicating that individual ponds are often genetically distinct. Estimates of landscape resistance suggest that ponds on either side of the Los Angeles Basin were likely interconnected historically, but intense urban development has rendered them essentially isolated, and the resulting risk of interruption to natural metapopulation dynamics appears to be high. Resistance surfaces show that the existing artificial ponds were well-placed and connected to natural populations by low-resistance corridors. Toad samples from all ponds (natural and artificial) returned extremely low estimates of effective population size, possibly due to a bottleneck caused by a recent multi-year drought. Management efforts should focus on maintaining gene flow among natural and artificial ponds by both assisted migration and construction of new ponds to bolster the existing pond network in the region.
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http://dx.doi.org/10.1093/jhered/esaa049DOI Listing
December 2020

Identification of seizure clusters using free text notes in an electronic seizure diary.

Epilepsy Behav 2020 12 20;113:107498. Epub 2020 Oct 20.

Stanford Department of Neurology and Neurological Sciences, USA.

Significance: Online seizure diaries offer a wealth of information regarding real world experience of patients living with epilepsy. Free text notes (FTN) written by patients reflect concerns and priorities of patients and provide supplemental information to structured diary data.

Objective: This project evaluated feasibility using an automated lexical analysis to identify FTN relevant to seizure clusters (SCs).

Methods: Data were extracted from EpiDiary™, a free electronic epilepsy diary with 42,799 unique users, generating 1,096,168 entries and 247,232 FTN. Both structured data as well as FTN were analyzed for presence of SC. A pilot study was conducted to validate an automated lexical analysis algorithm to identify SC in FTN in a sample of 98 diaries. The lexical analysis was then applied to the entire dataset. Outcomes included cluster prevalence and frequency, as well as the types of triggers commonly reported.

Results: At least one FTN was found among 13,987 (32.68%) individual diaries. An automated lexical analysis algorithm identified 5797 of FTN as SC. There were 2423 unique patients with SC that were not identified by structured data alone and were identified using lexical analysis of FTN only. Seizure clusters were identified in n = 10,331 (24.1%) of diary users through both structured data and FTN. The median number of SCs days per year was 13.7, (interquartile rank (IQR): 3.2-54.7). The median number of seizures in a cluster day was 3 (IQR 2-4). The most common missed medication linked to patients with SC was levetiracetam (n = 576, 29%) followed by lamotrigine (n = 495, 24%), topiramate (n = 208, 10.5%), carbamazepine (n = 190, 9.6%), and lacosamide (n = 170, 8.6%). These percentages generally reflected prevalence of medication use in this population. The use of rescue medications was documented in 3306 of structured entries and 4305 in FTN.

Conclusion: This exploratory study demonstrates a novel approach applying lexical analysis to previously untapped FTN in a large electronic seizure diary database. Free text notes captured information about SC not available from the structured diary data. Diary FTN contain information of high importance to people with epilepsy, written in their own words.
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http://dx.doi.org/10.1016/j.yebeh.2020.107498DOI Listing
December 2020

Incremental Unsupervised Domain-Adversarial Training of Neural Networks.

IEEE Trans Neural Netw Learn Syst 2020 Oct 7;PP. Epub 2020 Oct 7.

In the context of supervised statistical learning, it is typically assumed that the training set comes from the same distribution that draws the test samples. When this is not the case, the behavior of the learned model is unpredictable and becomes dependent upon the degree of similarity between the distribution of the training set and the distribution of the test set. One of the research topics that investigates this scenario is referred to as domain adaptation (DA). Deep neural networks brought dramatic advances in pattern recognition and that is why there have been many attempts to provide good DA algorithms for these models. Herein we take a different avenue and approach the problem from an incremental point of view, where the model is adapted to the new domain iteratively. We make use of an existing unsupervised domain-adaptation algorithm to identify the target samples on which there is greater confidence about their true label. The output of the model is analyzed in different ways to determine the candidate samples. The selected samples are then added to the source training set by self-labeling, and the process is repeated until all target samples are labeled. This approach implements a form of adversarial training in which, by moving the self-labeled samples from the target to the source set, the DA algorithm is forced to look for new features after each iteration. Our results report a clear improvement with respect to the non-incremental case in several data sets, also outperforming other state-of-the-art DA algorithms.
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http://dx.doi.org/10.1109/TNNLS.2020.3025954DOI Listing
October 2020

Epileptogenic network of focal epilepsies mapped with cortico-cortical evoked potentials.

Clin Neurophysiol 2020 Nov 2;131(11):2657-2666. Epub 2020 Sep 2.

Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; Stereotactic and Functional Neurosurgery Laboratory, Beijing Neurosurgical Institute, Capital Medical University, Beijing, China; Beijing Key Laboratory of Neurostimulation, Beijing, China. Electronic address:

Objective: The goal of this study was to investigate the spatial extent and functional organization of the epileptogenic network through cortico-cortical evoked potentials (CCEPs) in patients being evaluated with intracranial stereoelectroencephalography.

Methods: We retrospectively included 25 patients. We divided the recorded sites into three regions: epileptogenic zone (EZ); propagation zone (PZ); and noninvolved zone (NIZ). The root mean square of the amplitudes was calculated to reconstruct effective connectivity network. We also analyzed the N1/N2 amplitudes to explore the responsiveness influenced by epileptogenicity. Prognostic analysis was performed by comparing intra-region and inter-region connectivity between seizure-free and non-seizure-free groups.

Results: Our results confirmed that stimulation of the EZ caused the strongest responses on other sites within and outside the EZ. Moreover, we found a hierarchical connectivity pattern showing the highest connectivity strength within EZ, and decreasing connectivity gradient from EZ, PZ to NIZ. Prognostic analysis indicated a stronger intra-EZ connection in the seizure-free group.

Conclusion: The EZ showed highest excitability and dominantly influenced other regions. Quantitative CCEPs can be useful in mapping epileptic networks and predicting surgical outcome.

Significance: The generated computational connectivity model may enhance our understanding of epileptogenic networks and provide useful information for surgical planning and prognosis prediction.
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http://dx.doi.org/10.1016/j.clinph.2020.08.012DOI Listing
November 2020

On the relative (un)importance of foveal vision during letter search in naturalistic scenes.

Vision Res 2020 12 19;177:41-55. Epub 2020 Sep 19.

Psychology Department, School of Philosophy, Psychology and Language Sciences, University of Edinburgh, UK; Institute of Psychology, University of Kiel, Germany. Electronic address:

The importance of high-acuity foveal vision to visual search can be assessed by denying foveal vision using the gaze-contingent Moving Mask technique. Foveal vision was necessary to attain normal performance when searching for a target letter in alphanumeric displays, Perception & Psychophysics, 62 (2000) 576-585. In contrast, foveal vision was not necessary to correctly locate and identify medium-sized target objects in natural scenes, Journal of Experimental Psychology: Human Perception and Performance, 40 (2014) 342-360. To explore these task differences, we used grayscale pictures of real-world scenes which included a target letter (Experiment 1: T, Experiment 2: T or L). To reduce between-scene variability with regard to target salience, we developed the Target Embedding Algorithm (T.E.A.) to place the letter in a location for which there was a median change in local contrast when inserting the letter into the scene. The presence or absence of foveal vision was crossed with four target sizes. In both experiments, search performance decreased for smaller targets, and was impaired when searching the scene without foveal vision. For correct trials, the process of target localization remained completely unimpaired by the foveal scotoma, but it took longer to accept the target. We reasoned that the size of the target may affect the importance of foveal vision to the task, but the present data remain ambiguous. In summary, the data highlight the importance of extrafoveal vision for target localization, and the importance of foveal vision for target verification during letter-in-scene search.
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http://dx.doi.org/10.1016/j.visres.2020.07.005DOI Listing
December 2020

Does the virus cross the road? Viral phylogeographic patterns among bobcat populations reflect a history of urban development.

Evol Appl 2020 Sep 20;13(8):1806-1817. Epub 2020 Feb 20.

School of Natural Sciences University of Tasmania Hobart TAS Australia.

Urban development has major impacts on connectivity among wildlife populations and is thus likely an important factor shaping pathogen transmission in wildlife. However, most investigations of wildlife diseases in urban areas focus on prevalence and infection risk rather than potential effects of urbanization on transmission itself. Feline immunodeficiency virus (FIV) is a directly transmitted retrovirus that infects many felid species and can be used as a model for studying pathogen transmission at landscape scales. We investigated phylogenetic relationships among FIV isolates sampled from five bobcat () populations in coastal southern California that appear isolated due to major highways and dense urban development. Divergence dates among FIV phylogenetic lineages in several cases reflected historical urban growth and construction of major highways. We found strong FIV phylogeographic structure among three host populations north-west of Los Angeles, largely coincident with host genetic structure. In contrast, relatively little FIV phylogeographic structure existed among two genetically distinct host populations south-east of Los Angeles. Rates of FIV transfer among host populations did not vary significantly, with the lack of phylogenetic structure south-east of Los Angeles unlikely to reflect frequent contemporary transmission among populations. Our results indicate that major barriers to host gene flow can also act as barriers to pathogen spread, suggesting potentially reduced susceptibility of fragmented populations to novel directly transmitted pathogens. Infrequent exchange of FIV among host populations suggests that populations would best be managed as distinct units in the event of a severe disease outbreak. Phylogeographic inference of pathogen transmission is useful for estimating the ability of geographic barriers to constrain disease spread and can provide insights into contemporary and historical drivers of host population connectivity.
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http://dx.doi.org/10.1111/eva.12927DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7463333PMC
September 2020

Slender salamanders (genus ) reveal Southern California to be a center for the diversification, persistence, and introduction of salamander lineages.

PeerJ 2020 14;8:e9599. Epub 2020 Aug 14.

Museum of Vertebrate Zoology, University of California, Berkeley, CA, United States of America.

Background: The southern California biodiversity hotspot has had a complex geological history, with both plate tectonic forces and sea level changes repeatedly reconfiguring the region, and likely driving both lineage splittings and extinctions. Here we investigate patterns of genetic divergence in two species of slender salamanders (Plethodontidae: ) in this region. The complex geological history in combination with several organismal traits led us to predict that these species harbor multiple ancient mitochondrial lineages endemic to southern California. These species belong to a clade characterized by fine-scale mitochondrial structure, which has been shown to track ancient splits. Both focal species, and , are relatively widely distributed in southern California, and estimated to have persisted there across millions of years. Recently several extralimital populations of were found in the San Joaquin Valley of California, a former desert area that has been extensively modified for agriculture. The origins of these populations are unknown, but based on morphology, they are hypothesized to result from human-mediated introductions of .

Methods: We sequenced the mitochondrial gene from a geographically comprehensive sampling of the mitochondrial lineages of and that are endemic to southern California. We used phylogenetic analyses to characterize phylogeographic structure and identify mitochondrial contact zones. We also included the San Joaquin Valley samples to test whether they resulted from introductions. We used a bootstrap resampling approach to compare the strength of isolation-by-distance in both species and four other salamander species with which they co-occur in southern California.

Results: The northern lineage of harbors at least eight deeply differentiated, geographically cohesive mitochondrial subclades. We identify geographic contact between many of these mtDNA lineages and some biogeographic features that are concordant with lineage boundaries. also has multiple deeply differentiated clades within the region. Comparative analyses highlight the smaller spatial scales over which mitochondrial divergence accumulates in relative to most other salamander species in southern California. The extralimital populations of from the San Joaquin Valley are assigned to and are shown to result from at least two independent introductions from different source populations. We also suggest that on Catalina Island, where it is considered native, may be the result of an introduction. Some of the same traits that facilitate the build-up of deep phylogeographic structure in likely also contribute to its propensity for introductions, and we anticipate that additional introduced populations will be discovered.
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http://dx.doi.org/10.7717/peerj.9599DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7430267PMC
August 2020

Distinct Cdk9-phosphatase switches act at the beginning and end of elongation by RNA polymerase II.

Nat Commun 2020 08 28;11(1):4338. Epub 2020 Aug 28.

Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029-6574, USA.

Reversible phosphorylation of Pol II and accessory factors helps order the transcription cycle. Here, we define two kinase-phosphatase switches that operate at different points in human transcription. Cdk9/cyclin T1 (P-TEFb) catalyzes inhibitory phosphorylation of PP1 and PP4 complexes that localize to 3' and 5' ends of genes, respectively, and have overlapping but distinct specificities for Cdk9-dependent phosphorylations of Spt5, a factor instrumental in promoter-proximal pausing and elongation-rate control. PP1 dephosphorylates an Spt5 carboxy-terminal repeat (CTR), but not Spt5-Ser666, a site between Kyrpides-Ouzounis-Woese (KOW) motifs 4 and 5, whereas PP4 can target both sites. In vivo, Spt5-CTR phosphorylation decreases as transcription complexes pass the cleavage and polyadenylation signal (CPS) and increases upon PP1 depletion, consistent with a PP1 function in termination first uncovered in yeast. Depletion of PP4-complex subunits increases phosphorylation of both Ser666 and the CTR, and promotes redistribution of promoter-proximally paused Pol II into gene bodies. These results suggest that switches comprising Cdk9 and either PP4 or PP1 govern pause release and the elongation-termination transition, respectively.
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http://dx.doi.org/10.1038/s41467-020-18173-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7455706PMC
August 2020

Aneurysm Growth After Endovascular Sealing of Abdominal Aortic Aneurysms (EVAS) with the Nellix Endoprosthesis.

Eur J Vasc Endovasc Surg 2020 Nov 15;60(5):671-676. Epub 2020 Aug 15.

Institute of Translational Medicine, University of Liverpool, UK; School of Physical Sciences, University of Liverpool, UK; Liverpool Cardiovascular Service, Liverpool, UK; Liverpool Vascular & Endovascular Service, Liverpool, UK; Institute of Medicine, University of Chester, UK.

Objective: The aim of this study was to measure the incidence of post endovascular aneurysm sealing (EVAS) abdominal aortic aneurysm (AAA) growth, and its association with stent migration, in a cohort of patients with differing compliance to old and new Instructions For Use (IFU).

Methods: A retrospective single centre study was conducted to review the computed tomography (CT) and clinical data of elective, infrarenal EVAS cases, performed as a primary intervention, between December 2013 and March 2018. All included patients had a baseline post-operative CT scan at one month and at least one year follow up. The primary outcome measure was the incidence of AAA growth and its association with stent migration. AAA growth was defined as a ≥5% increase in aortic volume between the lowermost renal artery and the aortic bifurcation post EVAS at any time during follow up, in comparison to the baseline CT scan. Migration was defined according to the ESVS guidelines, as > 10 mm downward movement of either Nellix stent frame in the proximal zone.

Results: Seventy-six patients were eligible for inclusion in the study (mean age 76 ± 7.4 years; 58 men). AAA growth was identified in 50 of 76 patients (66%); adherence to IFU did not affect its incidence (mean growth within IFU-2016 compliant cohort vs. non-compliant: 16% vs. 13%, p = .33). Over time, the incidence of AAA growth increased, from 32% at one year to 100% at four years. AAA growth by volume was progressive (p < .001), as its extent increased over time. Migration was detected in 16 patients and there was a statistically significant association with AAA growth (13 patients displayed migration and AAA growth, p = .036).

Conclusion: Patients treated with EVAS are prone to AAA growth, irrespective of whether their aortic anatomy is IFU compliant. AAA growth by volume is associated with stent migration. Clinicians should continue close surveillance post EVAS, regardless of whether patients are treated within IFU.
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http://dx.doi.org/10.1016/j.ejvs.2020.07.013DOI Listing
November 2020

Management of a Compromised Frozen Elephant Trunk Due to Acute Type B Aortic Dissection.

Vasc Endovascular Surg 2020 Nov 13;54(8):756-759. Epub 2020 Aug 13.

Thoracic Aortic Aneurysm Service, Liverpool Centre for Cardiovascular Sciences, 156669Liverpool Heart and Chest Hospital, Liverpool, United Kingdom.

Purpose: To report a case who required a thoracic endovascular stenting (TEVAR) following the deployment of frozen elephant trunk due to false lumen expansion.

Case Report: A 47 years old male patient undergone emergency repair of acute type A aortic dissection in 2011 with bioprosthetic aortic root conduit. Seven years later he presented with moderate aortic valve disease and expanding chronic dissection of the aortic arch, therefore a redo operation with replacement of the prosthetic aortic valve, ascending aorta, total arch and deployment of frozen elephant trunk and he was discharged in good health. Several days post discharge he presented with new onset of chest pain and a new dissection involved the thoracoabdominal aorta was noted pressing on the true lumen and the frozen elephant trunk. Following a multi-disciplinary team meeting, TEVAR was deemed as a most appropriate approach and this was achieved successfully, and patient was discharged. At 1 year of follow up, he remains well and asymptomatic.

Conclusion: Close imaging follow-up following deployment of a FET is mandatory. A new acute Type B aortic dissection distal to the FET, that causes false lumen propagation parallel to the stented portion, is a surgical emergency and further intervention mandated.
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http://dx.doi.org/10.1177/1538574420949313DOI Listing
November 2020

Batrachochytrium salamandrivorans (Bsal) not detected in an intensive survey of wild North American amphibians.

Sci Rep 2020 08 3;10(1):13012. Epub 2020 Aug 3.

National Wildlife Health Center, U.S. Geological Survey, Madison, WI, 53711, USA.

The salamander chytrid fungus (Batrachochytrium salamandrivorans [Bsal]) is causing massive mortality of salamanders in Europe. The potential for spread via international trade into North America and the high diversity of salamanders has catalyzed concern about Bsal in the U.S. Surveillance programs for invading pathogens must initially meet challenges that include low rates of occurrence on the landscape, low prevalence at a site, and imperfect detection of the diagnostic tests. We implemented a large-scale survey to determine if Bsal was present in North America designed to target taxa and localities where Bsal was determined highest risk to be present based on species susceptibility and geography. Our analysis included a Bayesian model to estimate the probability of occurrence of Bsal given our prior knowledge of the occurrence and prevalence of the pathogen. We failed to detect Bsal in any of 11,189 samples from 594 sites in 223 counties within 35 U.S. states and one site in Mexico. Our modeling indicates that Bsal is highly unlikely to occur within wild amphibians in the U.S. and suggests that the best proactive response is to continue mitigation efforts against the introduction and establishment of the disease and to develop plans to reduce impacts should Bsal establish.
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http://dx.doi.org/10.1038/s41598-020-69486-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7400573PMC
August 2020

RGB-D-Based Framework to Acquire, Visualize and Measure the Human Body for Dietetic Treatments.

Sensors (Basel) 2020 Jul 1;20(13). Epub 2020 Jul 1.

School of Informatics, University of Edinburgh, 10 Crichton St, Edinburgh EH8 9AB, UK.

This research aims to improve dietetic-nutritional treatment using state-of-the-art RGB-D sensors and virtual reality (VR) technology. Recent studies show that adherence to treatment can be improved using multimedia technologies. However, there are few studies using 3D data and VR technologies for this purpose. On the other hand, obtaining 3D measurements of the human body and analyzing them over time (4D) in patients undergoing dietary treatment is a challenging field. The main contribution of the work is to provide a framework to study the effect of 4D body model visualization on adherence to obesity treatment. The system can obtain a complete 3D model of a body using low-cost technology, allowing future straightforward transference with sufficient accuracy and realistic visualization, enabling the analysis of the evolution (4D) of the shape during the treatment of obesity. The 3D body models will be used for studying the effect of visualization on adherence to obesity treatment using 2D and VR devices. Moreover, we will use the acquired 3D models to obtain measurements of the body. An analysis of the accuracy of the proposed methods for obtaining measurements with both synthetic and real objects has been carried out.
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http://dx.doi.org/10.3390/s20133690DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7374426PMC
July 2020

Dissecting the Pol II transcription cycle and derailing cancer with CDK inhibitors.

Nat Chem Biol 2020 07 22;16(7):716-724. Epub 2020 Jun 22.

Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.

Largely non-overlapping sets of cyclin-dependent kinases (CDKs) regulate cell division and RNA polymerase II (Pol II)-dependent transcription. Here we review the molecular mechanisms by which specific CDKs are thought to act at discrete steps in the transcription cycle and describe the recent emergence of transcriptional CDKs as promising drug targets in cancer. We emphasize recent advances in understanding the transcriptional CDK network that were facilitated by development and deployment of small-molecule inhibitors with increased selectivity for individual CDKs. Unexpectedly, several of these compounds have also shown selectivity in killing cancer cells, despite the seemingly universal involvement of their target CDKs during transcription in all cells. Finally, we describe remaining and emerging challenges in defining functions of individual CDKs in transcription and co-transcriptional processes and in leveraging CDK inhibition for therapeutic purposes.
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http://dx.doi.org/10.1038/s41589-020-0563-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7914107PMC
July 2020

Historical museum collections and contemporary population studies implicate roads and introduced predatory bullfrogs in the decline of western pond turtles.

PeerJ 2020 12;8:e9248. Epub 2020 Jun 12.

Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA, USA.

The western pond turtle (WPT), recently separated into two paripatrically distributed species ( and ), is experiencing significant reductions in its range and population size. In addition to habitat loss, two potential causes of decline are female-biased road mortality and high juvenile mortality from non-native predatory bullfrogs (). However, quantitative analyses of these threats have never been conducted for either species of WPT. We used a combination of historical museum samples and published and unpublished field studies shared with us through personal communications with WPT field researchers (B. Shaffer, P. Scott, R. Fisher, C. Brown, R. Dagit, L. Patterson, T. Engstrom, 2019, personal communications) to quantify the effect of roads and bullfrogs on WPT populations along the west coast of the United States. Both species of WPT shift toward increasingly male biased museum collections over the last century, a trend consistent with increasing, female-biased road mortality. Recent WPT population studies revealed that road density and proximity were significantly associated with increasingly male-biased sex ratios, further suggesting female-biased road mortality. The mean body size of museum collections of , but not , has increased over the last 100 years, consistent with reduced recruitment and aging populations that could be driven by invasive predators. Contemporary WPT population sites that co-occur with bullfrogs had significantly greater average body sizes than population sites without bullfrogs, suggesting strong bullfrog predation on small WPT hatchlings and juveniles. Overall, our findings indicate that both species of WPT face demographic challenges which would have been difficult to document without the use of both historical data from natural history collections and contemporary demographic field data. Although correlational, our analyses suggest that female-biased road mortality and predation on small turtles by non-native bullfrogs are occurring, and that conservation strategies reducing both may be important for WPT recovery.
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http://dx.doi.org/10.7717/peerj.9248DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7295021PMC
June 2020

Cdk9 and H2Bub1 signal to Clr6-CII/Rpd3S to suppress aberrant antisense transcription.

Nucleic Acids Res 2020 07;48(13):7154-7168

Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.

Mono-ubiquitylation of histone H2B (H2Bub1) and phosphorylation of elongation factor Spt5 by cyclin-dependent kinase 9 (Cdk9) occur during transcription by RNA polymerase II (RNAPII), and are mutually dependent in fission yeast. It remained unclear whether Cdk9 and H2Bub1 cooperate to regulate the expression of individual genes. Here, we show that Cdk9 inhibition or H2Bub1 loss induces intragenic antisense transcription of ∼10% of fission yeast genes, with each perturbation affecting largely distinct subsets; ablation of both pathways de-represses antisense transcription of over half the genome. H2Bub1 and phospho-Spt5 have similar genome-wide distributions; both modifications are enriched, and directly proportional to each other, in coding regions, and decrease abruptly around the cleavage and polyadenylation signal (CPS). Cdk9-dependence of antisense suppression at specific genes correlates with high H2Bub1 occupancy, and with promoter-proximal RNAPII pausing. Genetic interactions link Cdk9, H2Bub1 and the histone deacetylase Clr6-CII, while combined Cdk9 inhibition and H2Bub1 loss impair Clr6-CII recruitment to chromatin and lead to decreased occupancy and increased acetylation of histones within gene coding regions. These results uncover novel interactions between co-transcriptional histone modification pathways, which link regulation of RNAPII transcription elongation to suppression of aberrant initiation.
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http://dx.doi.org/10.1093/nar/gkaa474DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7367204PMC
July 2020

Anti-seizure therapy with a long-term, implanted intra-cerebroventricular delivery system for drug-resistant epilepsy: A first-in-man study.

EClinicalMedicine 2020 May 3;22:100326. Epub 2020 May 3.

Cerebral Therapeutics, 12635 E. Montview Blvd., Aurora, CO 80010, Australia.

Background: A clinical feasibility study was undertaken at a single center of long-term intra-cerebroventricular drug delivery of the anti-seizure medication valproic acid, into the cerebrospinal fluid (CSF) in order to treat drug resistant focal seizures, using an implantable infusion system. The primary objective was to establish the dose range of VPA administered in this manner. Secondarily, safety, pharmacokinetics (PK) and a preliminary estimate of effectiveness were evaluated.

Methods: In this single arm study, five adult subjects, with 29-234 focal onset seizures per month from a seizure focus involving the mesial temporal lobe were implanted with the system (clinicaltrials.gov identifier NCT02899611). Oral valproic acid (VPA) had previously been ineffective in all subjects. Post-surgery, pharmacokinetic studies of CSF infused VPA were performed. Valproic acid doses were increased stepwise in a standardised protocol.

Findings: The procedure and implantation were well-tolerated by all subjects. Four subjects responded with > 50% seizure reduction at the highest tested dose of 160 mg/day. Two subjects experienced extended periods of complete seizure freedom. All five subjects reported significant quality of life improvement. No clinical dose limiting side effects were encountered and there was no evidence of local periventricular toxicity in three subjects who were evaluated with imaging (T2 MRI). Side effects included nausea and appetite loss but were not dose-limiting. Mean CSF valproic acid levels were 45 μg per ml (range 20-120 μg per ml), with corresponding serum levels of 4-14 μg per ml.  Subjects have received therapy for up to 2.5 years in total . The efficacy analysis presented focuses on the period of time with the current pump with a mean 12.5 months, range 11.5-15 months. Pump failure requiring reimplantation was a significant initial issue in all subjects but resolved with use of pumps suitably compatible with long-term exposure to valproic acid.

Interpretation: The study demonstrated that chronic intraventricular administration of valproic acid is safe and effective in subjects with medically refractory epilepsy over many months. The procedure for implanting the infusion system is safe and well-tolerated. High CSF levels are achieved with corresponding low serum levels and this therapy is shown to be effective despite unsuccessful earlier use of oral valproate preparations. Drug side effects were minimal.

Funding: The study was funded by Cerebral Therapeutics Inc., Suite 137 12635 East Montview Blvd Aurora CO 80045.
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http://dx.doi.org/10.1016/j.eclinm.2020.100326DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7205744PMC
May 2020

Establishment of brown anoles () across a southern California county and potential interactions with a native lizard species.

PeerJ 2020 8;8:e8937. Epub 2020 Apr 8.

Western Ecological Research Center, US Geological Survey, San Diego, CA, USA.

The brown anole, , is a native species to the Caribbean; however, has invaded multiple parts of the USA, including Florida, Louisiana, Hawai'i and more recently California. The biological impacts of invading California are currently unknown. Evidence from the invasion in Taiwan shows that they spread quickly and when immediate action is not taken eradication stops being a viable option. In Orange County, California, five urban sites, each less than 100 ha, were surveyed for an average of 49.2 min. Approximately 200 were seen and verified across all survey sites. The paucity of native lizards encountered during the surveys within these sites suggests little to no overlap between the dominant diurnal western fence lizard, , and . This notable lack of overlap could indicate a potentially disturbing reality that are driving local extirpations of .
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http://dx.doi.org/10.7717/peerj.8937DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7150543PMC
April 2020

Sounds of seizures.

Seizure 2020 May 18;78:86-90. Epub 2020 Mar 18.

Department of Neurology, Comprehensive Epilepsy Center, New York University School of Medicine, New York, NY, USA.

Purpose: A phase I feasibility study to determine the accuracy of identifying seizures based on audio recordings.

Methods: We systematically generated 166 audio clips of 30 s duration from 83 patients admitted to an epilepsy monitoring unit between 1/2015 and 12/2016, with one clip during a seizure period and one clip during a non-seizure control period for each patient. Five epileptologists performed a blinded review of the audio clips and rated whether a seizure occurred or not, and indicated the confidence level (low or high) of their rating. The accuracy of individual and consensus ratings were calculated.

Results: The overall performance of the consensus rating between the five epileptologists showed a positive predictive value (PPV) of 0.91 and a negative predictive value (NPV) of 0.66. The performance improved when confidence was high (PPV of 0.96, NPV of 0.70). The agreement between the epileptologists was moderate with a kappa of 0.584. Hyperkinetic (PPV 0.92, NPV 0.86) and tonic-clonic (PPV and NPV 1.00) seizures were most accurately identified. Seizures with automatisms only and non-motor seizures could not be accurately identified. Specific seizure-related sounds associated with accurate identification included disordered breathing (PPV and NPV 1.00), rhythmic sounds (PPV 0.93, NPV 0.80), and ictal vocalizations (PPV 1.00, NPV 0.97).

Conclusion: This phase I feasibility study shows that epileptologists are able to accurately identify certain seizure types from audio recordings when the seizures produce sounds. This provides guidance for the development of audio-based seizure detection devices and demonstrate which seizure types could potentially be detected.
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http://dx.doi.org/10.1016/j.seizure.2020.03.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7269794PMC
May 2020

Splice or Die: When MYC Is Driving, Transcription Needs NUAK1 to Avoid Fatal Pileups.

Authors:
Robert P Fisher

Mol Cell 2020 03;77(6):1157-1158

Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA. Electronic address:

In this issue of Molecular Cell, Cossa et al. (2020) uncover the basis for a dependency of tumor cells with deregulated MYC on the kinase NUAK1, which acts through PP1 and PNUTS to ensure that splicing keeps up with MYC-driven transcription.
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http://dx.doi.org/10.1016/j.molcel.2020.02.025DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7910809PMC
March 2020

Cortical Excitability, Synaptic Plasticity, and Cognition in Benign Epilepsy With Centrotemporal Spikes: A Pilot TMS-EMG-EEG Study.

J Clin Neurophysiol 2020 Mar;37(2):170-180

Division of Adult Epilepsy, Stanford University School of Medicine, Stanford, California, U.S.A.

Purpose: Children with benign epilepsy with centrotemporal spikes have rare seizures emerging from the motor cortex, which they outgrow in adolescence, and additionally may have language deficits of unclear etiology. We piloted the use of transcranial magnetic stimulation paired with EMG and EEG (TMS-EMG, TMS-EEG) to test the hypotheses that net cortical excitability decreases with age and that use-dependent plasticity predicts learning.

Methods: We assessed language and motor learning in 14 right-handed children with benign epilepsy with centrotemporal spikes. We quantified two TMS metrics of left motor cortex excitability: the resting motor threshold (measure of neuronal membrane excitability) and amplitude of the N100-evoked potential (an EEG measure of GABAergic tone). To test plasticity, we applied 1 Hz repetitive TMS to the motor cortex to induce long-term depression-like changes in EMG- and EEG-evoked potentials.

Results: Children with benign epilepsy with centrotemporal spikes tolerate TMS; no seizures were provoked. Resting motor threshold decreases with age but is elevated above maximal stimulator output for half the group. N100 amplitude decreases with age after controlling for resting motor threshold. Motor cortex plasticity correlates significantly with language learning and at a trend level with motor learning.

Conclusions: Transcranial magnetic stimulation is safe and feasible for children with benign epilepsy with centrotemporal spikes, and TMS-EEG provides more reliable outcome measures than TMS-EMG in this group because many children have unmeasurably high resting motor thresholds. Net cortical excitability decreases with age, and motor cortex plasticity predicts not only motor learning but also language learning, suggesting a mechanism by which motor cortex seizures may interact with language development.
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http://dx.doi.org/10.1097/WNP.0000000000000662DOI Listing
March 2020

Amphibian responses in the aftermath of extreme climate events.

Sci Rep 2020 02 25;10(1):3409. Epub 2020 Feb 25.

Pepperdine University, Natural Science Division, 24255 Pacific Coast Highway, Malibu, CA, 90263, USA.

Climate change-induced extinctions are estimated to eliminate one in six known species by the end of the century. One major factor that will contribute to these extinctions is extreme climatic events. Here, we show the ecological impacts of recent record warm air temperatures and simultaneous peak drought conditions in California. From 2008-2016, the southern populations of a wide-ranging endemic amphibian (the California newt, Taricha torosa) showed a 20% reduction to mean body condition and significant losses to variation in body condition linked with extreme climate deviations. However, body condition in northern populations remained relatively unaffected during this period. Range-wide population estimates of change to body condition under future climate change scenarios within the next 50 years suggest that northern populations will mirror the loss of body condition recently observed in southern populations. This change is predicated on latter 21 century climate deviations that resemble recent conditions in Southern California. Thus, the ecological consequences of climate change have already occurred across the warmer, drier regions of Southern California, and our results suggest that predicted climate vulnerable regions in the more mesic northern range likely will not provide climate refuge for numerous amphibian communities.
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http://dx.doi.org/10.1038/s41598-020-60122-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7042276PMC
February 2020

Automatic Hierarchical Classification of Kelps Using Deep Residual Features.

Sensors (Basel) 2020 Jan 13;20(2). Epub 2020 Jan 13.

School of Biological Sciences and Oceans Institute, The University of Western Australia, Crawley, WA 6009, Australia.

Across the globe, remote image data is rapidly being collected for the assessment of benthic communities from shallow to extremely deep waters on continental slopes to the abyssal seas. Exploiting this data is presently limited by the time it takes for experts to identify organisms found in these images. With this limitation in mind, a large effort has been made globally to introduce automation and machine learning algorithms to accelerate both classification and assessment of marine benthic biota. One major issue lies with organisms that move with swell and currents, such as kelps. This paper presents an automatic hierarchical classification method local binary classification as opposed to the conventional flat classification to classify kelps in images collected by autonomous underwater vehicles. The proposed kelp classification approach exploits learned feature representations extracted from deep residual networks. We show that these generic features outperform the traditional off-the-shelf CNN features and the conventional hand-crafted features. Experiments also demonstrate that the hierarchical classification method outperforms the traditional parallel multi-class classifications by a significant margin (90.0% vs. 57.6% and 77.2% vs. 59.0%) on Benthoz15 and Rottnest datasets respectively. Furthermore, we compare different hierarchical classification approaches and experimentally show that the sibling hierarchical training approach outperforms the inclusive hierarchical approach by a significant margin. We also report an application of our proposed method to study the change in kelp cover over time for annually repeated AUV surveys.
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http://dx.doi.org/10.3390/s20020447DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7013955PMC
January 2020

Adjunctive repetitive transcranial magnetic stimulation delivers superior quality of life for focal epilepsy compared to anti-epileptic drugs: A meta-analytic utility prediction study.

Brain Stimul 2020 Mar - Apr;13(2):430-432. Epub 2019 Dec 12.

Department of Neurosurgery, Stanford University Medical Center, 300 Pasteur Drive, Stanford, CA, 94305, USA. Electronic address:

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http://dx.doi.org/10.1016/j.brs.2019.12.006DOI Listing
December 2019

Tripolar concentric EEG electrodes reduce noise.

Clin Neurophysiol 2020 01 22;131(1):193-198. Epub 2019 Nov 22.

Stanford University Department of Neurology and Neurological Sciences, Palo Alto, CA 94304, USA. Electronic address:

Objective: To assay EEG signal quality recorded with tripolar concentric ring electrodes (TCREs) compared to regular EEG electrodes.

Methods: EEG segments were recorded simultaneously by TCREs and regular electrodes, low-pass filtered at 35 Hz (REG35) and 70 Hz (REG70). Clips were rated blindly by nine electroencephalographers for presence or absence of key EEG features, relative to the "gold-standard" of the clinical report.

Results: TCRE showed less EMG artifact (F = 15.4, p < 0.0001). Overall quality rankings were not significantly different. Focal slowing was better detected by TCRE and spikes were better detected by regular electrodes. Seizures (n = 85) were detected by TCRE in 64 cases (75.3%), by REG70 in 75 (88.2%) and REG35 in 69 (81.2%) electrodes. TCRE detected 9 (10.6%) seizures not detected by one of the other 2 methods. In contrast, 14 seizures (16.5%) were not detected by TCRE, but were by REG35 electrodes. Each electrode detected interictal spikes when the other did not.

Conclusions: TCRE produced similar overall quality and confidence ratings versus regular electrodes, but less muscle artifact. TCRE recordings detected seizures in 7% of instances where regular electrodes did not.

Significance: The combination of the two types increased detection of epileptiform events compared to either alone.
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http://dx.doi.org/10.1016/j.clinph.2019.10.022DOI Listing
January 2020

Urbanization reduces genetic connectivity in bobcats (Lynx rufus) at both intra- and interpopulation spatial scales.

Mol Ecol 2019 12 12;28(23):5068-5085. Epub 2019 Nov 12.

School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia.

Urbanization is a major factor driving habitat fragmentation and connectivity loss in wildlife. However, the impacts of urbanization on connectivity can vary among species and even populations due to differences in local landscape characteristics, and our ability to detect these relationships may depend on the spatial scale at which they are measured. Bobcats (Lynx rufus) are relatively sensitive to urbanization and the status of bobcat populations is an important indicator of connectivity in urban coastal southern California. We genotyped 271 bobcats at 13,520 SNP loci to conduct a replicated landscape resistance analysis in five genetically distinct populations. We tested urban and natural factors potentially influencing individual connectivity in each population separately, as well as study-wide. Overall, landscape genomic effects were most frequently detected at the study-wide spatial scale, with urban land cover (measured as impervious surface) having negative effects and topographic roughness having positive effects on gene flow. The negative effect of urban land cover on connectivity was also evident when populations were analyzed separately despite varying substantially in spatial area and the proportion of urban development, confirming a pervasive impact of urbanization largely independent of spatial scale. The effect of urban development was strongest in one population where stream habitat had been lost to development, suggesting that riparian corridors may help mitigate reduced connectivity in urbanizing areas. Our results demonstrate the importance of replicating landscape genetic analyses across populations and considering how landscape genetic effects may vary with spatial scale and local landscape structure.
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http://dx.doi.org/10.1111/mec.15274DOI Listing
December 2019