An Imaging Mass Spectrometry Investigation Into the N-linked Glycosylation Landscape of Pancreatic Ductal Adenocarcinoma and the Development of Associated Tools for Enhanced Glycan Separation and Characterization

The severity of pancreatic ductal adenocarcinoma (PDAC) is largely attributed to a failure to detect the disease before metastatic spread has occurred. CA19-9, a carbohydrate biomarker, is used clinically to surveille disease progression, but due to specificity challenges is not suitable for early discovery. As CA19-9 and other prospective markers are glycan epitopes, there is great clinical interest in understanding the glycobiology of pancreatic cancer. Unfortunately, few studies have been able to link glycosylation changes directly to pancreatic tumors and instead have focused on peripheral glycan alterations in the serum of PDAC patients. To address this gap in our understanding, we applied an imaging mass spectrometry (IMS) approach with complementary enzymatic and chemical isomer separation techniques to spatially assess the PDAC N-glycome in a cohort of pancreatic cancer patients. Orthogonally, we characterized the expression of CA19-9 and a new biomarker, sTRA, by multi-round immunofluorescence (IF) in the same cohort. These analyses revealed increased sialylation, fucosylation and branching amongst other structural themes in areas of PDAC tumor tissue. CA19-9 expressing tumors were defined by multiply branched, fucosylated bisecting N-glycans while sTRA expressing tumors favored tetraantennary N-glycans with polylactosamine extensions. IMS and IF-derived glycan and biomarker features were used to build classification models that detected PDAC tissue with an AUC of 0.939, outperforming models using either dataset individually. While studying sialylation isomers in our PDAC cohort, we saw an opportunity to enhance the chemical derivatization protocol we were using to address its shortcomings and expand its functionality. Subsequently, we developed a set of novel amidation-amidation strategies to stabilize and differentially label 2,3 and 2,6-linked sialic acids. In our alkyne-based approach, the differential mass shifts induced by the reactions allow for isomeric discrimination in imaging mass spectrometry experiments. This scheme, termed AAXL, was further characterized in clinical tissue specimens, biofluids and cultured cells. Our azide-based approach, termed AAN3, was more suitable for bioorthogonal applications, where the azide tag installed on 2,3 and 2,8-sialic acids could be reacted by click chemistry with a biotin-alkyne for subsequent streptavidin-peroxidase staining. Furthering the use of AAN3, we developed two additional techniques to fluorescently label (SAFER) and preferentially enrich (SABER) 2,3 and 2,8-linked sialic acids for more advanced glycomic applications. Initial experiments with these novel approaches have shown successful fluorescent staining and the identification of over 100 sialylated glycoproteins by LC-MS/MS. These four bioorthogonal strategies provide a new glycomic tool set for the characterization of sialic acid isomers in pancreatic and other cancers. Overall, this work furthers our collective understanding of the glycobiology underpinning pancreatic cancer and potentiates the discovery of novel carbohydrate biomarkers for the early detection of PDAC

Judgment and the identity theory of truth

The identity theory of truth takes on different forms depending on whether it is combined with a dual relation or a multiple relation theory of judgment. This paper argues that there are two significant problems for the dual relation identity theorist regarding thought's answerability to reality, neither of which takes a grip on the multiple relation identity theory

The efficacy of good practice to prevent long-term leaching losses of phosphorus from an irrigated dairy farm

Phosphorus (P) can be leached from intensive land uses, including grazed dairy farming. There is some evidence to suggest that P-leaching can enrich groundwater, especially where fertiliser or farm dairy effluent P (FDE) is applied to soils of low sorption capacity. We measured P fractions in leachate at 70 cm depth from two soils of low-P sorption capacity in an intensively grazed dairy farm, one a free-draining shallow soil and another a deep and moderately well-drained soil. As per industry good practice, the soils were maintained at an agronomic optimum and received P as either fertiliser or a lower rate of fertiliser plus FDE, applied according to regional rules and industry guidelines to avoid the FDE ponding on the soil surface and leaching to depth. Our hypothesis was that rules and guidelines were not sufficient to prevent P losses, especially in the free-draining soil. In response to annual applications of 40 kg P ha⁻¹ yr⁻¹ as fertiliser or 30 kg P ha⁻¹ yr⁻¹ as fertiliser and 10 kg P ha⁻¹ yr⁻¹ as FDE, dissolved and particulate P concentrations increased annually 4 to 7%. Mean total P load over the 14-yr period of measurement (2001–2015) from the FDE-treated, free-draining shallow soil was 1.46 kg ha⁻¹ yr⁻¹, much greater than the same soil without FDE (0.25 kg ha⁻¹ yr⁻¹) or the moderately well-drained soil with or without FDE applied (0.12 kg ha⁻¹ yr⁻¹, for both treatments). Leaching losses were attributed to a combination of high hydraulic conductivity enhanced by the presence of macropores and the increasing P saturation of macropore walls. An enrichment in dissolved reactive P was also detected in a well intercepting groundwater at 10-m depth. However, the source of the enrichment was unclear. These data suggest that despite following industry good practice, regional rules and industry guidelines significant P losses may occur when FDE is applied to soil at rates designed to maintain soil Olsen P in an agronomically optimal concentration. It is unclear if applying less FDE at lower rate, would decrease P losses. Therefore, less P must be applied, made less available for loss, or P-rich FDE not applied to this freely draining shallow stony soil (or similar soils) under irrigation

Epidemiological study of E. coli O157:H7 isolated in Northern Ireland using pulsed-field gel electrophoresis (PFGE)

In Northern Ireland over the last 7 years, there is a mean of 41.9 laboratory reports per annum of human gastrointestinal infection (range 19-54) caused by Escherichia coli O157:H7. In the preceding years 1992-1996, reports were 5.4 per annum, whereas in 1997-2000, reports increased from 30 to 54 per annum. This high level has continued on an annual basis to date. The aim of this study was therefore to retrospectively examine this period of exponential increase in reports to help ascertain the genetic relatedness of strains employing pulsed-field gel electrophoresis (PFGE), as no data on the molecular epidemiology of E. coli O157:H7 in Northern Ireland has yet been published. Clinical isolates (n=84) were PFGE typed employing Xba I digestion and resulting band profiles demonstrated the presence of 13, 9 and 16 clonal types, for 1997, 1998 and 1999, respectively. In 1998, five clonal types remained from 1997 with the introduction of 4 new clonal types, whereas in 1999, 10 new clonal types were observed, accounting for over half (58%) of the E. coli O157 isolates for that year. These data suggest that, unlike gastrointestinal infections due to thermophilic campylobacters, there was considerable genetic evolution of PFGE clonal types of E. coli O157, through the displacement and emergence of genotypes. Further studies are now required to find the environmental reservoirs of these common clonal types of clinical E. coli O157:H7 in Northern Ireland to help define sources and routes of transmission of this infection locally

Feminist Reflections on the Scope of Labour Law: Domestic Work, Social Reproduction and Jurisdiction

Drawing on feminist labour law and political economy literature, I argue that it is crucial to interrogate the personal and territorial scope of labour. After discussing the “commodification” of care, global care chains, and body work, I claim that the territorial scope of labour law must be expanded beyond that nation state to include transnational processes. I use the idea of social reproduction both to illustrate and to examine some of the recurring regulatory dilemmas that plague labour markets. I argue that unpaid care and domestic work performed in the household, typically by women, troubles the personal scope of labour law. I use the example of this specific type of personal service relation to illustrate my claim that the jurisdiction of labour law is historical and contingent, rather than conceptual and universal. I conclude by identifying some of the implications of redrawing the territorial and personal scope of labour law in light of feminist understandings of social reproduction

Population health metrics: crucial inputs to the development of evidence for health policy

Valid, reliable and comparable measures of the health states of individuals and of the health status of populations are critical components of the evidence base for health policy. We need to develop population health measurement strategies that coherently address the relationships between epidemiological measures (such as risk exposures, incidence, and mortality rates) and multi-domain measures of population health status, while ensuring validity and cross-population comparability. Studies reporting on descriptive epidemiology of major diseases, injuries and risk factors, and on the measurement of health at the population level – either for monitoring trends in health levels or inequalities or for measuring broad outcomes of health systems and social interventions – are not well-represented in traditional epidemiology journals, which tend to concentrate on causal studies and on quasi-experimental design. In particular, key methodological issues relating to the clear conceptualisation of, and the validity and comparability of measures of population health are currently not addressed coherently by any discipline, and cross-disciplinary debate is fragmented and often conducted in mutually incomprehensible language or paradigms. Population health measurement potentially bridges a range of currently disjoint fields of inquiry relating to health: biology, demography, epidemiology, health economics, and broader social science disciplines relevant to assessment of health determinants, health state valuations and health inequalities. This new journal will focus on the importance of a population based approach to measurement as a way to characterize the complexity of people's health, the diseases and risks that affect it, its distribution, and its valuation, and will attempt to provide a forum for innovative work and debate that bridge the many fields of inquiry relevant to population health in order to contribute to the development of valid and comparable methods for the measurement of population health and its determinants

The Grail of original meaning : uses of the past in American constitutional theory

Originalist jurisprudence, which enjoins a faithful adherence to the values enshrined in the late eighteenth-century Constitution, has become a prominent feature of contemporary American conservatism. Recovering the original meaning of the Constitution is far from straightforward, and raises major issues of historical interpretation. How far do the assumed historical underpinnings of originalist interpretation mesh with the findings of academic historians? To what extent has the conservative invocation of the Founding Fathers obscured a lost American Enlightenment? Nor is ‘tradition’ in American Constitutional law an unproblematic matter. How far does a desire to restore the original meaning of the Constitution ignore the role of ‘stare decisis’ (precedent) in America's common law heritage? It transpires, moreover, that the various schemes of historical interpretation in American Constitutional jurisprudence do not map easily onto a simple liberal–conservative divide.PostprintPeer reviewe

A ‘living fossil’ eel (Anguilliformes: Protanguillidae, fam. nov.) from an undersea cave in Palau

We report the discovery of an enigmatic, small eel-like fish from a 35 m-deep fringing-reef cave in the western Pacific Ocean Republic of Palau that exhibits an unusual suite of morphological characters. Many of these uniquely characterize the Recent members of the 19 families comprising the elopomorph order Anguilliformes, the true eels. Others are found among anguilliforms only in the Cretaceous fossils, and still others are primitive with respect to both Recent and fossil eels. Thus, morphological evidence explicitly places it as the most basal lineage (i.e. the sister group of extant anguilliforms). Phylogenetic analysis and divergence time estimation based on whole mitogenome sequences from various actinopterygians, including representatives of all eel families, demonstrate that this fish represents one of the most basal, independent lineages of the true eels, with a long evolutionary history comparable to that of the entire Anguilliformes (approx. 200 Myr). Such a long, independent evolutionary history dating back to the early Mesozoic and a retention of primitive morphological features (e.g. the presence of a premaxilla, metapterygoid, free symplectic, gill rakers, pseudobranch and distinct caudal fin rays) warrant recognition of this species as a ‘living fossil’ of the true eels, herein described as Protanguilla palau genus et species nov. in the new family Protanguillidae

Consensus Recommendation for Mouse Models of Ocular Hypertension to Study Aqueous Humor Outflow and Its Mechanisms.

Due to their similarities in anatomy, physiology, and pharmacology to humans, mice are a valuable model system to study the generation and mechanisms modulating conventional outflow resistance and thus intraocular pressure. In addition, mouse models are critical for understanding the complex nature of conventional outflow homeostasis and dysfunction that results in ocular hypertension. In this review, we describe a set of minimum acceptable standards for developing, characterizing, and utilizing mouse models of open-angle ocular hypertension. We expect that this set of standard practices will increase scientific rigor when using mouse models and will better enable researchers to replicate and build upon previous findings