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The Effect of Haptic Feedback on Efficiency and Safety During Preretinal Membrane Peeling Simulation.
PurposeWe determine whether haptic feedback improves surgical performance and outcome during simulated a preretinal membrane peeling procedure.MethodsA haptic-enabled virtual reality preretinal membrane peeling simulator was developed using a surgical cockpit with two multifinger haptic devices. Six subjects (three trained retina surgeons and three nonsurgeons) performed the preretinal membrane peeling surgical procedure using two modes of operation: visual and haptic feedback, and visual feedback only.ResultsTask completion time, tool tip path trajectory, tool-retina collision force, and retinal damage were all reduced with haptic feedback used and compared to modes where haptic feedback was disabled.ConclusionsHaptic feedback improves efficiency and safety during preretinal membrane peeling simulation.Translational relevanceThese findings highlight the potential benefit of haptic feedback for improving performance and safety of vitreoretinal surgery
Genetic targeting of arginase-ii in mouse prevents renal oxidative stress and inflammation in diet-induced obesity
Obesity is associated with development and progression of chronic kidney disease (CKD). Recent evidence demonstrates that enhanced levels of the L- arginine:ureahydrolase, including the two isoenzymes arginase-I (Arg-I) and arginase- II (Arg-II) in vascular endothelial cells promote uncoupling of endothelial nitric oxide synthase (eNOS), leading to increased superoxide radical anion and decreased NO production thereby endothelial dysfunction. Arg-II but not Arg-I is abundantly expressed in kidney and the role of Arg-II in CKD is uncertain and controversial. We aimed to investigate the role of Arg-II in renal damage associated with diet-induced obesity mouse model. Wild type (WT) C57BL/6 mice and mice deficient in Arg-II gene (Arg-II−/−) were fed with either a normal chow (NC) or a high-fat-diet (HFD) for 14 weeks (starting at the age of 7 weeks) to induce obesity. In WT mice, HFD feeding caused frequent renal lipid accumulation, enhancement of renal reactive oxygen species (ROS) levels which could be attenuated by a NOS inhibitor, suggesting uncoupling of NOS in kidney. HFD feeding also significantly augmented renal Arg-II expression and activity. All the alterations in the kidney under HFD feeding were reduced in Arg-II−/− mice. Moreover, mesangial expansion as analyzed by Periodic Acid Schiff (PAS) staining and renal expression of vascular adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) in HFD-fed WT mouse assessed by immunoblotting were reduced in the HFD-fed Arg- II−/− mice, although there was no significant difference in body weight and renal weight/body weight ratio between the WT and Arg-II−/− mice. Thus, Arg-II expression/activity is enhanced in kidney of diet-induced obesity mice. Genetic targeting of Arg-II prevents renal damage associated with obesity, suggesting an important role of Arg-II in obesity-associated renal disease development
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The Histone Deacetylase SIRT6 Restrains Transcription Elongation via Promoter-Proximal Pausing.
Transcriptional regulation in eukaryotes occurs at promoter-proximal regions wherein transcriptionally engaged RNA polymerase II (Pol II) pauses before proceeding toward productive elongation. The role of chromatin in pausing remains poorly understood. Here, we demonstrate that the histone deacetylase SIRT6 binds to Pol II and prevents the release of the negative elongation factor (NELF), thus stabilizing Pol II promoter-proximal pausing. Genetic depletion of SIRT6 or its chromatin deficiency upon glucose deprivation causes intragenic enrichment of acetylated histone H3 at lysines 9 (H3K9ac) and 56 (H3K56ac), activation of cyclin-dependent kinase 9 (CDK9)-that phosphorylates NELF and the carboxyl terminal domain of Pol II-and enrichment of the positive transcription elongation factors MYC, BRD4, PAF1, and the super elongation factors AFF4 and ELL2. These events lead to increased expression of genes involved in metabolism, protein synthesis, and embryonic development. Our results identified SIRT6 as a Pol II promoter-proximal pausing-dedicated histone deacetylase
La escala de Likert de 5 ítems y la correspondencia de la escala de porcentaje con implicaciones para el uso de modelos con variables lingüísticas (difusas)
The aim of this paper is to examine how people perceive correspondence between the 5-item Likert scale and the percentage scale (the LS-PS correspondence thereinafter). Are all five items of the Likert scale equidistant? Do people use the same scale when evaluating different objects? Are men and women different? Are people from different countries / cultures different? The method of the study was a questionnaire with 661 participating respondents altogether from the Czech Republic, Ecuador, and France. The results indicate that the 5-item Likert scale is neither equidistant, nor symmetrical. Furthermore, there are (highly) statistically significant differences in the LS-PS correspondence with respect to location, age, or gender of respondents. The results can be used as an input for more precise decision-making modeling associated with (fuzzy) linguistic variables.El objetivo de este trabajo es examinar cómo las personas perciben la correspondencia entre la escala Likert de 5 ítems y la escala de porcentaje (la correspondencia LS-PS en adelante). ¿Los cinco elementos de la escala Likert son equidistantes? ¿La gente usa la misma escala al evaluar diferentes objetos? ¿Se diferencian hombres y mujeres? ¿Son diferentes las personas de diferentes países / culturas? El método del estudio fue un cuestionario con 661 encuestados participantes de la República Checa, Ecuador y Francia. Los resultados indican que la escala Likert de 5 ítems no es ni equidistante ni simétrica. Además, existen diferencias (altamente) estadísticamente significativas en la correspondencia LS-PS con respecto a la ubicación, edad o género de los encuestados. Los resultados se pueden utilizar como entrada para un modelo de toma de decisiones más preciso asociado con variables lingüísticas (difusas).Universidad Pablo de Olavid
A Novel Hantavirus of the European Mole, Bruges Virus, Is Involved in Frequent Nova Virus Coinfections
Hantaviruses are zoonotic viruses with a complex evolutionary history of
virus–host coevolution and cross-species transmission. Although hantaviruses
have a broad reservoir host range, virus–host relationships were previously
thought to be strict, with a single virus species infecting a single host
species. Here, we describe Bruges virus, a novel hantavirus harbored by the
European mole (Talpa europaea), which is the well-known host of Nova virus.
Phylogenetic analyses of all three genomic segments showed tree topology
inconsistencies, suggesting that Bruges virus has emerged from cross-species
transmission and ancient reassortment events. A high number of coinfections
with Bruges and Nova viruses was detected, but no evidence was found for
reassortment between these two hantaviruses. These findings highlight the
complexity of hantavirus evolution and the importance of further investigation
of hantavirus–reservoir relationships
Addressing Beacon Re-Identification Attacks: Quantification and Mitigation of Privacy Risks
The Global Alliance for Genomics and Health (GA4GH) created the Beacon Project as a means of testing the willingness of data holders to share genetic data in the simplest technical context query for the presence of a specified nucleotide at a given position within a chromosome. Each participating site (or “beacon”) is responsible for assuring that genomic data are exposed through the Beacon service only with the permission of the individual to whom the data pertains, and in accordance with the GA4GH policy and standards. While recognizing the inference risks associated with large-scale data aggregation, and the fact that some beacons contain sensitive phenotypic associations that increase privacy risk, the GA4GH adjudged the risk of re-identification based on the binary yes/no allele-presence query responses as acceptable. However, recent work demonstrated that, given a beacon with specific characteristics (including relatively small sample size, and an adversary who possesses an individual’s whole genome sequence), the individual’s membership in a beacon can be inferred through repeated queries for variants present in the individual’s genome. In this paper, we propose three practical strategies for reducing re-identification risks in beacons. The first two strategies manipulate the beacon such that the presence of rare alleles is obscured; the third strategy budgets the number of accesses per user for each individual genome. Using a beacon containing data from the 1000 Genomes Project, we demonstrate that the proposed strategies can effectively reduce re-identification risk in beacon-like datasets
Cross-National Differences in Victimization : Disentangling the Impact of Composition and Context
Varying rates of criminal victimization across countries are assumed to be the outcome of countrylevel structural constraints that determine the supply ofmotivated o¡enders, as well as the differential composition within countries of suitable targets and capable guardianship. However, previous empirical tests of these ‘compositional’ and ‘contextual’ explanations of cross-national di¡erences
have been performed upon macro-level crime data due to the unavailability of comparable individual-level data across countries. This limitation has had two important consequences for cross-national crime research. First, micro-/meso-level mechanisms underlying cross-national differences cannot be truly inferred from macro-level data. Secondly, the e¡ects of contextual measures (e.g. income inequality) on crime are uncontrolled for compositional heterogeneity. In this
paper, these limitations are overcome by analysing individual-level victimization data across 18 countries from the International CrimeVictims Survey. Results from multi-level analyses on theft and violent victimization indicate that the national level of income inequality is positively related to risk, independent of compositional (i.e. micro- and meso-level) di¡erences. Furthermore, crossnational variation in victimization rates is not only shaped by di¡erences in national context, but
also by varying composition. More speci¢cally, countries had higher crime rates the more they consisted of urban residents and regions with lowaverage social cohesion.
LKB1/AMPK and PKA Control ABCB11 Trafficking and Polarization in Hepatocytes.
Polarization of hepatocytes is manifested by bile canalicular network formation and activation of LKB1 and AMPK, which control cellular energy metabolism. The bile acid, taurocholate, also regulates development of the canalicular network through activation of AMPK. In the present study, we used collagen sandwich hepatocyte cultures from control and liver-specific LKB1 knockout mice to examine the role of LKB1 in trafficking of ABCB11, the canalicular bile acid transporter. In polarized hepatocytes, ABCB11 traffics from Golgi to the apical plasma membrane and endogenously cycles through the rab 11a-myosin Vb recycling endosomal system. LKB1 knockout mice were jaundiced, lost weight and manifested impaired bile canalicular formation and intracellular trafficking of ABCB11, and died within three weeks. Using live cell imaging, fluorescence recovery after photobleaching (FRAP), particle tracking, and biochemistry, we found that LKB1 activity is required for microtubule-dependent trafficking of ABCB11 to the canalicular membrane. In control hepatocytes, ABCB11 trafficking was accelerated by taurocholate and cAMP; however, in LKB1 knockout hepatocytes, ABCB11 trafficking to the apical membrane was greatly reduced and restored only by cAMP, but not taurocholate. cAMP acted through a PKA-mediated pathway which did not activate AMPK. Our studies establish a regulatory role for LKB1 in ABCB11 trafficking to the canalicular membrane, hepatocyte polarization, and canalicular network formation
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