1,518 research outputs found
V1647 Orionis: Reinvigorated Accretion and the Re-Appearance of McNeil's Nebula
In late 2003, the young eruptive variable star V1647 Orionis optically
brightened by over 5 magnitudes, stayed bright for around 26 months, and then
decline to its pre-outburst level. In August 2008 the star was reported to have
unexpectedly brightened yet again and we herein present the first detailed
observations of this new outburst. Photometrically, the star is now as bright
as it ever was following the 2003 eruption. Spectroscopically, a pronounced P
Cygni profile is again seen in Halpha with an absorption trough extending to
-700 km/s. In the near-infrared, the spectrum now possesses very weak CO
overtone bandhead absorption in contrast to the strong bandhead emission seen
soon after the 2003 event. Water vapor absorption is also much stronger than
previously seen. We discuss the current outburst below and relate it to the
earlier event.Comment: 6 pages, 3 figure
Reversibilidade de bens na concessão do serviço telefônico fixo comutado : uma análise crítica na perspectiva da Teoria Responsiva da Regulação
Dissertação (mestrado)—Universidade de Brasília, Faculdade de Direito, Curso de Pós-Graduação em Direito, 2017.A presente dissertação investiga as possíveis consequências de mutações paradigmáticas do direito administrativo no contorno jurídico de um instituto considerado, tradicionalmente, intrínseco às concessões de serviço de telecomunicações: a reversão de bens. O estudo evidencia a relação das alterações doutrinárias dos institutos jurídicos do direito administrativo com a persistência dos bens reversíveis nas concessões de serviços de telecomunicações. Destarte, a linha investigativa do trabalho identifica se o instituto da reversibilidade de bens na concessão de serviço público de telecomunicações é, ainda, a única ou melhor forma de se atingir os fins por ele visados, em especial a continuidade do serviço. Em relação ao marco teórico, adotou-se a teoria responsiva da regulação, tal como concebida por Ian Ayres e John Braithwaite no livro Responsive Regulation: Transcending the Deregulation Debate, de 1992, e desdobramentos de pesquisas posteriores. A pesquisa inicia com investigação sobre o novo papel a ser desempenhado pela Administração Pública em sua atuação em geral e, especificamente, no âmbito regulatório. Em seguida, propõe-se a adoção da teoria responsiva da regulação como modelagem teórica adequada para conciliar uma nova forma de atuação administrativa com a proteção dos interesses públicos. Após um aprofundamento sobre as principais proposições da teoria responsiva, foram analisados a doutrina e o arcabouço normativo sobre o tema dos bens reversíveis no setor de telecomunicações, propondo-se, ao final, uma crítica à regulamentação atual e fornecendo-se uma possível modelagem que seguisse os ditames da teoria responsiva da regulação.This study investigates the possible consequences of paradigmatic changes in Administrative Law in the legal context of an institute considered, at least traditionally, intrinsic to telecommunications service in Brazil: the reversal to the public domain or to a new service provider of assets owned by the current service provider. It is intended to highlight the relationship between the doctrinal changes in the legal institutes of Administrative Law and the persistence of the reversible assets in telecommunications service. Thus, the investigative line of the work will seek to know if the institute of the reversibility of asset in public telecommunications services is still the only or the better way to achieve its goals, especially the continuity of the service, from the perspective of the theory of responsive regulation, as conceived by Ian Ayres and John Braithwaite in the book Responsive Regulation: Transcending the Deregulation Debate, 1992. The research begins with developments on the new role to be played by the Public Administration, not least in the regulatory arena. Next, the study tackles the appropriateness of the theory of responsive regulation to reconcile a new form of administrative action with the protection of public interests. After that the main propositions of the theory of responsive regulation, the doctrine and the normative framework on the subject of reversible assets in the telecommunications sector were analyzed. Finally, a critique of current state of the art of the regulation and proposals providing a possible modeling that follows the dictates of the Responsive Theory of Regulation were made
IL-27 induces an IFN-like signature in murine macrophages which in turn modulate colonic epithelium
Mucosal delivery of IL-27 has been shown to have a therapeutic benefit in murine models of inflammatory bowel disease (IBD). The IL-27 effect was associated with phosphorylated STAT1 (pSTAT1), a product of IL27 receptor signaling, in bowel tissue. To determine whether IL-27 acted directly on colonic epithelium, murine colonoids and primary intact colonic crypts were shown to be unresponsive to IL-27 in vitro and to lack detectable IL-27 receptors. On the other hand, macrophages, which are present in inflamed colon tissue, were responsive to IL-27 in vitro. IL-27 induced pSTAT1 in macrophages, the transcriptome indicated an IFN-like signature, and supernatants induced pSTAT1 in colonoids. IL-27 induced anti-viral activity in macrophages and MHC Class II induction. We conclude that the effects of mucosal delivery of IL-27 in murine IBD are in part based on the known effects of IL27 inducing immunosuppression of T cells mediated by IL-10. We also conclude that IL-27 has potent effects on macrophages in inflamed colon tissue, generating mediators that in turn act on colonic epithelium
Language and reading impairments are associated with increased prevalence of non-right handedness
Funding: Royal Society - UF150663, RGF\EA\180141; Wellcome Trust - 217065/Z/19/Z; H2020 European Research Council - 694189; NWO - 451-15-017; National Health and Medical Research Council - 1173896; Canadian Institute for Health Research - MOP-133440.Handedness has been studied for association with language-related disorders because of its link with language hemispheric dominance. No clear pattern has emerged, possibly because of small samples, publication bias, and heterogeneous criteria across studies. Non-right-handedness (NRH) frequency was assessed in N = 2503 cases with reading and/or language impairment and N = 4316 sex-matched controls identified from 10 distinct cohorts (age range 6–19 years old; European ethnicity) using a priori set criteria. A meta-analysis (Ncases = 1994) showed elevated NRH % in individuals with language/reading impairment compared with controls (OR = 1.21, CI = 1.06–1.39, p = .01). The association between reading/language impairments and NRH could result from shared pathways underlying brain lateralization, handedness, and cognitive functions.Publisher PDFPeer reviewe
Genetic variants and functional pathways associated with resilience to Alzheimer\u27s disease.
Approximately 30% of older adults exhibit the neuropathological features of Alzheimer\u27s disease without signs of cognitive impairment. Yet, little is known about the genetic factors that allow these potentially resilient individuals to remain cognitively unimpaired in the face of substantial neuropathology. We performed a large, genome-wide association study (GWAS) of two previously validated metrics of cognitive resilience quantified using a latent variable modelling approach and representing better-than-predicted cognitive performance for a given level of neuropathology. Data were harmonized across 5108 participants from a clinical trial of Alzheimer\u27s disease and three longitudinal cohort studies of cognitive ageing. All analyses were run across all participants and repeated restricting the sample to individuals with unimpaired cognition to identify variants at the earliest stages of disease. As expected, all resilience metrics were genetically correlated with cognitive performance and education attainment traits (P-values \u3c 2.5 × 10-20), and we observed novel correlations with neuropsychiatric conditions (P-values \u3c 7.9 × 10-4). Notably, neither resilience metric was genetically correlated with clinical Alzheimer\u27s disease (P-values \u3e 0.42) nor associated with APOE (P-values \u3e 0.13). In single variant analyses, we observed a genome-wide significant locus among participants with unimpaired cognition on chromosome 18 upstream of ATP8B1 (index single nucleotide polymorphism rs2571244, minor allele frequency = 0.08, P = 2.3 × 10-8). The top variant at this locus (rs2571244) was significantly associated with methylation in prefrontal cortex tissue at multiple CpG sites, including one just upstream of ATPB81 (cg19596477; P = 2 × 10-13). Overall, this comprehensive genetic analysis of resilience implicates a putative role of vascular risk, metabolism, and mental health in protection from the cognitive consequences of neuropathology, while also providing evidence for a novel resilience gene along the bile acid metabolism pathway. Furthermore, the genetic architecture of resilience appears to be distinct from that of clinical Alzheimer\u27s disease, suggesting that a shift in focus to molecular contributors to resilience may identify novel pathways for therapeutic targets
Plasmid-Cured Chlamydia caviae Activates TLR2-Dependent Signaling and Retains Virulence in the Guinea Pig Model of Genital Tract Infection
Loss of the conserved “cryptic” plasmid from C. trachomatis and C. muridarum is pleiotropic, resulting in reduced innate inflammatory activation via TLR2, glycogen accumulation and infectivity. The more genetically distant C. caviae GPIC is a natural pathogen of guinea pigs and induces upper genital tract pathology when inoculated intravaginally, modeling human disease. To examine the contribution of pCpGP1 to C. caviae pathogenesis, a cured derivative of GPIC, strain CC13, was derived and evaluated in vitro and in vivo. Transcriptional profiling of CC13 revealed only partial conservation of previously identified plasmid-responsive chromosomal loci (PRCL) in C. caviae. However, 2-deoxyglucose (2DG) treatment of GPIC and CC13 resulted in reduced transcription of all identified PRCL, including glgA, indicating the presence of a plasmid-independent glucose response in this species. In contrast to plasmid-cured C. muridarum and C. trachomatis, plasmid-cured C. caviae strain CC13 signaled via TLR2 in vitro and elicited cytokine production in vivo similar to wild-type C. caviae. Furthermore, inflammatory pathology induced by infection of guinea pigs with CC13 was similar to that induced by GPIC, although we observed more rapid resolution of CC13 infection in estrogen-treated guinea pigs. These data indicate that either the plasmid is not involved in expression or regulation of virulence in C. caviae or that redundant effectors prevent these phenotypic changes from being observed in C. caviae plasmid-cured strains
Sex differences in the genetic architecture of cognitive resilience to Alzheimer\u27s disease.
Approximately 30% of elderly adults are cognitively unimpaired at time of death despite the presence of Alzheimer\u27s disease neuropathology at autopsy. Studying individuals who are resilient to the cognitive consequences of Alzheimer\u27s disease neuropathology may uncover novel therapeutic targets to treat Alzheimer\u27s disease. It is well established that there are sex differences in response to Alzheimer\u27s disease pathology, and growing evidence suggests that genetic factors may contribute to these differences. Taken together, we sought to elucidate sex-specific genetic drivers of resilience. We extended our recent large scale genomic analysis of resilience in which we harmonized cognitive data across four cohorts of cognitive ageing, in vivo amyloid PET across two cohorts, and autopsy measures of amyloid neuritic plaque burden across two cohorts. These data were leveraged to build robust, continuous resilience phenotypes. With these phenotypes, we performed sex-stratified [n (males) = 2093, n (females) = 2931] and sex-interaction [n (both sexes) = 5024] genome-wide association studies (GWAS), gene and pathway-based tests, and genetic correlation analyses to clarify the variants, genes and molecular pathways that relate to resilience in a sex-specific manner. Estimated among cognitively normal individuals of both sexes, resilience was 20-25% heritable, and when estimated in either sex among cognitively normal individuals, resilience was 15-44% heritable. In our GWAS, we identified a female-specific locus on chromosome 10 [rs827389, β (females) = 0.08, P (females) = 5.76 × 10-09, β (males) = -0.01, P(males) = 0.70, β (interaction) = 0.09, P (interaction) = 1.01 × 10-04] in which the minor allele was associated with higher resilience scores among females. This locus is located within chromatin loops that interact with promoters of genes involved in RNA processing, including GATA3. Finally, our genetic correlation analyses revealed shared genetic architecture between resilience phenotypes and other complex traits, including a female-specific association with frontotemporal dementia and male-specific associations with heart rate variability traits. We also observed opposing associations between sexes for multiple sclerosis, such that more resilient females had a lower genetic susceptibility to multiple sclerosis, and more resilient males had a higher genetic susceptibility to multiple sclerosis. Overall, we identified sex differences in the genetic architecture of resilience, identified a female-specific resilience locus and highlighted numerous sex-specific molecular pathways that may underly resilience to Alzheimer\u27s disease pathology. This study illustrates the need to conduct sex-aware genomic analyses to identify novel targets that are unidentified in sex-agnostic models. Our findings support the theory that the most successful treatment for an individual with Alzheimer\u27s disease may be personalized based on their biological sex and genetic context
Neutrophil Extracellular Traps in Breast Cancer and Beyond: Current Perspectives on NET Stimuli, Thrombosis and Metastasis, and Clinical Utility for Diagnosis and Treatment
Abstract
The formation of neutrophil extracellular traps (NETs), known as NETosis, was first observed as a novel immune response to bacterial infection, but has since been found to occur abnormally in a variety of other inflammatory disease states including cancer. Breast cancer is the most commonly diagnosed malignancy in women. In breast cancer, NETosis has been linked to increased disease progression, metastasis, and complications such as venous thromboembolism. NET-targeted therapies have shown success in preclinical cancer models and may prove valuable clinical targets in slowing or halting tumor progression in breast cancer patients. We will briefly outline the mechanisms by which NETs may form in the tumor microenvironment and circulation, including the crosstalk between neutrophils, tumor cells, endothelial cells, and platelets as well as the role of cancer-associated extracellular vesicles in modulating neutrophil behavior and NET extrusion. The prognostic implications of cancer-associated NETosis will be explored in addition to development of novel therapeutics aimed at targeting NET interactions to improve outcomes in patients with breast cancer
Development and validation of a targeted gene sequencing panel for application to disparate cancers
Next generation sequencing has revolutionised genomic studies of cancer, having facilitated the development of precision oncology treatments based on a tumour’s molecular profile. We aimed to develop a targeted gene sequencing panel for application to disparate cancer types with particular focus on tumours of the head and neck, plus test for utility in liquid biopsy. The final panel designed through Roche/Nimblegen combined 451 cancer-associated genes (2.01 Mb target region). 136 patient DNA samples were collected for performance and application testing. Panel sensitivity and precision were measured using well-characterised DNA controls (n = 47), and specificity by Sanger sequencing of the Aryl Hydrocarbon Receptor Interacting Protein (AIP) gene in 89 patients. Assessment of liquid biopsy application employed a pool of synthetic circulating tumour DNA (ctDNA). Library preparation and sequencing were conducted on Illumina-based platforms prior to analysis with our accredited (ISO15189) bioinformatics pipeline. We achieved a mean coverage of 395x, with sensitivity and specificity of >99% and precision of >97%. Liquid biopsy revealed detection to 1.25% variant allele frequency. Application to head and neck tumours/cancers resulted in detection of mutations aligned to published databases. In conclusion, we have developed an analytically-validated panel for application to cancers of disparate types with utility in liquid biopsy
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