Publications by authors named "Roy H"

The transfer RNA (tRNA)-dependent pathway for lipid aminoacylation is a two-step pathway composed of (1) a tRNA aminoacylation step catalyzed by an aminoacyl-tRNA synthetase, forming a specific aa-tRNA, and (2) a tRNA-dependent transfer step in which the amino acid acylating the tRNA is transferred to an acceptor lipid. The latter step is catalyzed by a transferase located within the cytoplasmic membrane of certain bacteria. Lipid aminoacylation modifies the biochemical properties of the membrane and enhances resistance of some pathogens to various classes of antimicrobial agents and components of the innate immune response.

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Action to reduce anthropogenic impact on the environment and species within it will be most effective when targeted towards activities that have the greatest impact on biodiversity. To do this effectively we need to better understand the relative importance of different activities and how they drive changes in species' populations. Here, we present a novel, flexible framework that reviews evidence for the relative importance of these drivers of change and uses it to explain recent alterations in species' populations.

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Background: Recently there has been increasing focus on monitoring pollinating insects, due to concerns about their declines, and interest in the role of volunteers in monitoring pollinators, particularly bumblebees, via citizen science.

Methodology / Principal Findings: The Big Bumblebee Discovery was a one-year citizen science project run by a partnership of EDF Energy, the British Science Association and the Centre for Ecology & Hydrology which sought to assess the influence of the landscape at multiple scales on the diversity and abundance of bumblebees. Timed counts of bumblebees (Bombus spp.

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The hydrothermal mats, mounds, and chimneys of the southern Guaymas Basin are the surface expression of complex subsurface hydrothermal circulation patterns. In this overview, we document the most frequently visited features of this hydrothermal area with photographs, temperature measurements, and selected geochemical data; many of these distinct habitats await characterization of their microbial communities and activities. Microprofiler deployments on microbial mats and hydrothermal sediments show their steep geochemical and thermal gradients at millimeter-scale vertical resolution.

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Introduction: Clinical pharmacy has developed since the 1960s in North America, with large disparities in the presence of decentralized pharmacists in hospital units between healthcare programs. Decentralized pharmacists have been present in pediatrics since the 1970s. The main objective of this study was to describe the steps used to upgrade the pediatrics department's pharmaceutical care.

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Alkanes are major constituents of crude oil and are released to the marine environment by natural seepage and from anthropogenic sources. Due to their chemical inertness, their removal from anoxic marine sediments is primarily controlled by the activity of anaerobic alkane-degrading microorganisms. To facilitate comprehensive cultivation-independent surveys of the diversity and distribution of anaerobic alkane degraders, we designed novel PCR primers that cover all known diversity of the 1-methylalkyl succinate synthase gene (masD/assA), which catalyzes the initial activation of alkanes.

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Background: The oral transmucosal (OTM) route for administration of comfort medication in infants at the end-of-life has long been favored by our pediatric palliative care team but has rarely been described in the literature.

Objective: To determine the feasibility of implementing a standardized comfort care protocol using OTM medications in dying neonates.

Method: A comfort protocol prescribing medication by the OTM route and standardized assessment were established.

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Iron is abundant in sediments, where it can be biogeochemically cycled between its divalent and trivalent redox states. The neutrophilic microbiological Fe cycle involves Fe(III)-reducing and three different physiological groups of Fe(II)-oxidizing microorganisms, i.e.

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Potassium salts of phenolate based polydentate xanthate ligands 4,4'-bis(2-dithiocarbonatobenzylideneamino)diphenyl ether () and 4,4'-bis(2-dithiocarbonatonaphthylmethylideneamino)diphenyl ether () have been synthesized and characterized, prior to use. The reaction of or with M(OAc)2 in Et3N affords access to a rare series of binuclear metallomacrocyclic xanthate complexes of the type [M2-μ(2)-bis-(κ(2)S,S-xan(1)/xan(2))] () which quickly forms [2 : 2] binuclear N,O-bidentate Schiff base macrocyclic complexes of the type [M2-μ(2)-bis-(κ(2)N,O-L(1)/L(2))] ( = 4,4'-bis(2-hydroxybenzylideneamino)diphenyl ether, = 4,4'-bis(2-hydroxynaphthylmethylidene-amino)diphenyl ether) via evolution of CS2 in solution. The compounds were characterized by microanalysis, relevant spectroscopy (FT-IR, UV-visible), mass spectrometry (ESI-MS), and powder and single crystal XRD techniques.

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Chromatin organization has a fundamental impact on the whole spectrum of genomic functions. Quantitative characterization of the chromatin structure, particularly at submicron length scales where chromatin fractal globules are formed, is critical to understanding this structure-function relationship. Such analysis is currently challenging due to the diffraction-limited resolution of conventional light microscopy.

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Objective: A major impediment to translating chemoprevention to clinical practice has been lack of intermediate biomarkers. We previously reported that rectal interrogation with low-coherence enhanced backscattering spectroscopy (LEBS) detected microarchitectural manifestations of field carcinogenesis. We now wanted to ascertain if reversion of two LEBS markers spectral slope (SPEC) and fractal dimension (FRAC) could serve as a marker for chemopreventive efficacy.

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Nesting of experimental factors is well established in statistical design literature related to agricultural, environmental and engineering studies. It is perhaps not sufficiently discussed in biological and laboratory experiments stemming from the use of human bio-specimens, where sample size considerations are often provided a priori , but there is little advice regarding the . Motivated by an example from spectroscopic microscopy and lung cancer, we revisit the experimental nesting frame work and discuss how variability, cost of sampling and sample size at lower levels may be coherently utilized.

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1. was first recorded in Britain in 2004. Two subsequent earlier records were received from 2003.

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Over the past decade, France has developed an electronic dose register at national level called SISERI. Institute for Radiological Protection and Nuclear Safety is in charge of the management of this information system. Besides the main purpose of being a central register of any doses measured for the individual dosimetric monitoring of all exposed workers, SISERI has been developed so as to constitute a tool for occupational physicians and radiation protection officers allowing access in real-time to the results of the individual monitoring.

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Volatile fatty acids (VFAs) are key intermediates in the anaerobic mineralization of organic matter in marine sediments. We studied the role of VFAs in the carbon and energy turnover in the sulfate reduction zone of sediments from the sub-arctic Godthåbsfjord (SW Greenland) and the adjacent continental shelf in the NE Labrador Sea. VFA porewater concentrations were measured by a new two-dimensional ion chromatography-mass spectrometry method that enabled the direct analysis of VFAs without sample pretreatment.

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MUC4, a large transmembrane mucin normally expressed in the small and large intestine, is differentially expressed during inflammatory and malignant conditions of the colon. However, the expression pattern and the role of MUC4 in colitis and colorectal cancer (CRC) are inconclusive. Therefore, the aim of this study was to understand the role of Muc4 during inflammatory and malignant conditions of the colon.

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Aminoacyl-phosphatidylglycerol synthases (aaPGSs) are membrane proteins that utilize aminoacylated tRNAs to modify membrane lipids with amino acids. Aminoacylation of membrane lipids alters the biochemical properties of the cytoplasmic membrane and enables bacteria to adapt to changes in environmental conditions. aaPGSs utilize alanine, lysine and arginine as modifying amino acids, and the primary lipid recipients have heretofore been defined as phosphatidylglycerol (PG) and cardiolipin.

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Lynch syndrome (LS) is the most common of all inherited cancer syndromes, associated with substantially elevated risks for colonic and extracolonic malignancies, earlier onset and high rates of multiple primary cancers. At the genetic level, it is caused by a defective mismatch repair (MMR) system due to presence of germline defects in at least one of the MMR genes- MLH1, MSH2, MSH6, PMS2 or EPCAM. An impaired MMR function during replication introduces infidelity in DNA sequence and leads to ubiquitous mutations at simple repetitive sequences (microsatellites), causing microsatellite instability (MSI).

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There are large variations in the responses of species to the environmental changes of recent decades, heightening interest in whether their traits may explain inter-specific differences in range expansions and contractions. Using a long-term distributional dataset, we calculated range changes of grasshoppers and crickets in Britain between the 1980s and the 2000s and assessed whether their traits (resource use, life history, dispersal ability, geographic location) explain relative performance of different species. Our analysis showed large changes in the distributions of some species, and we found a positive relationship between three traits and range change: ranges tended to increase for habitat generalists, species that oviposit in the vegetation above ground, and for those with a southerly distribution.

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Biodiversity is changing at unprecedented rates, and it is increasingly important that these changes are quantified through monitoring programmes. Previous recommendations for developing or enhancing these programmes focus either on the end goals, that is the intended use of the data, or on how these goals are achieved, for example through volunteer involvement in citizen science, but not both. These recommendations are rarely prioritized.

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Background: Appendicitis is a common pediatric query. However, obesity often results in nondiagnostic ultrasounds and increased likelihood of abdominal computed tomography (CT). Concern regarding radiation exposure led the Canadian Association of Radiologists to recommend foregoing CT when ultrasounds are nondiagnostic and clinical suspicion is high.

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Purpose: Colorectal cancer remains the second leading cause of cancer deaths in the United States despite being eminently preventable by colonoscopy via removal of premalignant adenomas. In order to more effectively reduce colorectal cancer mortality, improved screening paradigms are needed. Our group pioneered the use of low-coherence enhanced backscattering (LEBS) spectroscopy to detect the presence of adenomas throughout the colon via optical interrogation of the rectal mucosa.

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