25 research outputs found
Changes in chemical and ultrastructural composition of ameroid constrictors following in vitro expansion
ObjectiveTo (1) characterise the chemical and ultra-structural composition of ameroid constrictors, at a native state and during in vitro expansion and (2) determine the presence of irritant compounds at the surface or within the bulk of the constrictor.MethodsTwelve sterile, commercially packaged ameroid constrictors (3 repeats of 3.5 mm, 5 mm, 6 mm and 7 mm internal diameter) were analysed by time-of-flight secondary ion mass spectrometry, Raman spectroscopy, attenuated total reflectance Fourier transform infrared spectroscopy and scanning electron microscopy.ResultsAmeroid constrictors have a composition commensurate with casein with little-to-no intra- or inter- constrictor variation. Microscopic analysis indicated that the topographical features of the constrictor surfaces were consistent between all constrictors. Following in vitro expansion there was a reproducible decrease in Ca+ ion content, little-to-no variation in secondary protein structure and morphological changes including the presence of surface aggregates present only at the inner surface of the ameroid constrictor. The potential irritant polydimethylsiloxane was found on the constrictor surface. A trace quantity of an ion fragment assigned as formaldehyde was detected; however, the extremely low level is thought highly unlikely to play a role as an inflammatory trigger clinically.DiscussionThere is a high degree of inter- and intra-constrictor homogeneity from different batches, and reproducible ultrastructural changes following in vitro expansion. Variations occur in both the surface chemistry and topography of the device during closure, which can potentially affect the biomaterial-host interface. Ameroid constrictor closure mechanism is likely involving calcium-mediated inter-protein interactions rather than the imbibition of water only
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CYP3A7*1C allele: linking premenopausal oestrone and progesterone levels with risk of hormone receptor-positive breast cancers
Funder: Breast Cancer Now (BCN); doi: https://doi.org/10.13039/100009794Funder: Cancer Research UK (CRUK); doi: https://doi.org/10.13039/501100000289Funder: RCUK | Medical Research Council (MRC); doi: https://doi.org/10.13039/501100000265Funder: U.S. Department of Health & Human Services | National Institutes of Health (NIH)Funder: Wellcome Trust (Wellcome); doi: https://doi.org/10.13039/100004440Funder: EC | EC Seventh Framework Programm | FP7 Ideas: European Research Council (FP7-IDEAS-ERC - Specific Programme: "Ideas" Implementing the Seventh Framework Programme of the European Community for Research, Technological Development and Demonstration Activities (2007 to 2013)); doi: https://doi.org/10.13039/100011199; Grant(s): HEALTH-F2-2009-223175, HEALTH-F2-2009-223175Funder: Genome Canada (Génome Canada); doi: https://doi.org/10.13039/100008762Funder: Gouvernement du Canada | Canadian Institutes of Health Research (Instituts de Recherche en Santé du Canada); doi: https://doi.org/10.13039/501100000024Funder: Quebec Breast cancer Foundation Genome QuebecFunder: U.S. Department of Health & Human Services | NIH | U.S. National Library of Medicine (NLM); doi: https://doi.org/10.13039/100000092Funder: EC | EC Seventh Framework Programm | FP7 Ideas: European Research Council (FP7-IDEAS-ERC - Specific Programme: "Ideas" Implementing the Seventh Framework Programme of the European Community for Research, Technological Development and Demonstration Activities (2007 to 2013))Funder: European Union’s Horizon 2020Funder: Deutsche Krebshilfe (German Cancer Aid); doi: https://doi.org/10.13039/501100005972Funder: BCAST - European Union’s Horizon 2020Funder: Breast Cancer Now; doi: https://doi.org/10.13039/501100007913Abstract: Background: Epidemiological studies provide strong evidence for a role of endogenous sex hormones in the aetiology of breast cancer. The aim of this analysis was to identify genetic variants that are associated with urinary sex-hormone levels and breast cancer risk. Methods: We carried out a genome-wide association study of urinary oestrone-3-glucuronide and pregnanediol-3-glucuronide levels in 560 premenopausal women, with additional analysis of progesterone levels in 298 premenopausal women. To test for the association with breast cancer risk, we carried out follow-up genotyping in 90,916 cases and 89,893 controls from the Breast Cancer Association Consortium. All women were of European ancestry. Results: For pregnanediol-3-glucuronide, there were no genome-wide significant associations; for oestrone-3-glucuronide, we identified a single peak mapping to the CYP3A locus, annotated by rs45446698. The minor rs45446698-C allele was associated with lower oestrone-3-glucuronide (−49.2%, 95% CI −56.1% to −41.1%, P = 3.1 × 10–18); in follow-up analyses, rs45446698-C was also associated with lower progesterone (−26.7%, 95% CI −39.4% to −11.6%, P = 0.001) and reduced risk of oestrogen and progesterone receptor-positive breast cancer (OR = 0.86, 95% CI 0.82–0.91, P = 6.9 × 10–8). Conclusions: The CYP3A7*1C allele is associated with reduced risk of hormone receptor-positive breast cancer possibly mediated via an effect on the metabolism of endogenous sex hormones in premenopausal women
Impact of Cesarean Delivery and Breastfeeding on Secretory Immunoglobulin A in the Infant Gut Is Mediated by Gut Microbiota and Metabolites
How gut immunity in early life is shaped by birth in relation to delivery mode, intrapartum antibiotic prophylaxis (IAP) and labor remains undetermined. We aimed to address this gap with a study of secretory Immunoglobulin A (SIgA) in the infant gut that also tested SIgA-stimulating pathways mediated by gut microbiota and metabolites. Among 1017 Canadian full-term infants, gut microbiota of fecal samples collected at 3 and 12 months were profiled using 16S rRNA sequencing; C. difficile was quantified by qPCR; fecal metabolites and SIgA levels were measured by NMR and SIgA enzyme-linked immunosorbent assay, respectively. We assessed the putative causal relationships from birth events to gut microbiota and metabolites, and ultimately to SIgA, in statistical sequential mediation models, adjusted for maternal gravida status in 551 infants. As birth mode influences the ability to breastfeed, the statistical mediating role of breastfeeding status and milk metabolites was also evaluated. Relative to vaginal birth without maternal IAP, cesarean section (CS) after labor was associated with reduced infant gut SIgA levels at 3 months (6.27 vs. 4.85 mg/g feces, p C. difficile, and Streptococcus. The milk or microbial metabolites in CS-SIgA mediating pathways were galactose, fucose, GABA, choline, lactate, pyruvate and 1,2-propanediol. This cohort study documented the impact of birth on infant gut mucosal SIgA. It is the first to characterize gut microbe-metabolite mediated pathways for early-life SIgA maturation, pathways that require experimental verification
'A Divided Soul'? the Cold War odyssey of O. John Rogge
In 1948 O. John Rogge, a prominent American liberal, was a contender for the Progressive Party's vice-presidential nomination. He was then a man of the Left: an activist in the international peace movement, a champion of radical causes and a defender of organizations deemed subversive by the Department of Justice. In 1951 he persuaded his\ud
client to turn government witness in the Rosenberg espionage trial and was converted into 'Rogge the Rat' by his former allies. In tracing this transformation, this paper will argue that Rogge was neither a typical Cold War apostate nor a typical anti-Stalinist intellectual. Instead, his political trajectory was the outcome of a failed attempt to steer global politics away from Cold War dichotomies. The paper will therefore throw new light\ud
both on the movement to find a 'third way' between East and West, and on the phenomenon of non-communist Left activism during the early Cold War
Planetary opportunities: A social contract for global change science to contribute to a sustainable future
The global change research community needs to renew its social contract with society by moving beyond a focus on biophysical limits and toward solution-oriented research to provide realistic, context-specific pathways to a sustainable future. A focus on planetary opportunities is based on the premise that societies adapt to change and have historically implemented solutions-for example, to protect watersheds, improve food security, and reduce harmful atmospheric emissions. Daunting social and biophysical challenges for achieving a sustainable future demand that the global change research community work to provide underpinnings for workable solutions at multiple scales of governance. Global change research must reorient itself from a focus on biophysically oriented, global-scale analysis of humanity's negative impact on the Earth system to consider the needs of decisionmakers from household to global scales. © 2012 by American Institute of Biological Sciences