Publications by authors named "Barton I"

Article Synopsis
  • MucR is a transcriptional regulator found in Brucella species that influences gene expression related to virulence by binding to AT-rich DNA regions.
  • MucR is part of the Ros/MucR family in α-proteobacteria and shares functional similarities with H-NS proteins, although they lack sequence homology.
  • This study uses cryo-EM and other methods to reveal that MucR and its homolog Ml5 form a unique circular structure that can condense DNA, linking nucleoid structure to transcription regulation.
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Bacteria rely on DNA methylation for restriction-modification systems and epigenetic control of gene expression. Here, we use direct detection of methylated bases by nanopore sequencing to monitor global DNA methylation in Alphaproteobacteria, where use of this technique has not yet been reported. One representative of this order, , relies on DNA methylation to control cell cycle progression, but it is unclear whether other members of this order, such as , depend on the same systems.

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Article Synopsis
  • MucR is part of a protein family that plays a crucial role in regulating virulence and symbiosis genes in α-proteobacteria.
  • Recent research has redefined MucR from a classical transcriptional regulator to a unique Histone-like Nucleoid Structuring (H-NS) protein.
  • The review aims to compile genetic and biochemical evidence showing that MucR binds to AT-rich DNA regions, influencing gene expression differently than traditional regulators.
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Bacteria rely on DNA methylation for restriction-modification systems and epigenetic control of gene expression. Here, we use direct detection of methylated bases by nanopore sequencing to monitor global DNA methylation in Alphaproteobacteria, where use of this technique has not yet been reported. One representative of this order, , relies on DNA methylation to control cell cycle progression, but it is unclear whether other members of this order, such as , depend on the same systems.

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Histone-like nucleoid structuring (H-NS) and H-NS-like proteins coordinate host-associated behaviors in many pathogenic bacteria, often through forming silencer/counter-silencer pairs with signal-responsive transcriptional activators to tightly control gene expression. and related bacteria do not encode H-NS or homologs of known H-NS-like proteins, and it is unclear if they have other proteins that perform analogous functions during pathogenesis. In this work, we provide compelling evidence for the role of MucR as a novel H-NS-like protein in .

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We report on the electronic structure of vanadium in synthetic V-oxides and in natural roscoelite (V-rich phyllosilicate). This study applied electron energy-loss spectroscopy (EELS) in the scanning transmission electron microscope (STEM), combined with first-principle calculations, to (1) establish relationships between the V oxidation state and EELS L2,3 features and (2) better constrain the oxidation state and crystallographic siting of V in roscoelite, with implications for other V-bearing phyllosilicates. Both EELS measurements and band structure calculations show that the EELS L2/L3 ratio increases as the oxidation state of V increases.

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Objective: We explored the relationship between the Sleep Hygiene Practices Scale (SHPS) and sleep quality and sleep-related impairment in Black and Latinx adults with type 2 diabetes (T2DM).

Methods: Forty Black and Latinx adults with T2DM participated. Self-reported measures include the Pittsburg Sleep Quality Index (PSQI), Patient Reported Outcomes Measurement Information System (PROMIS) Sleep Disturbance (SD) and Sleep-Related Impairment (SRI) measures, and SHPS (domains include sleep schedule and timing, arousal-related behaviors, poor eating/drinking habits prior to sleep, and poor sleep environment).

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Many pathogens or symbionts of animals and plants contain multiple replicons, a configuration called a multipartite genome. Multipartite genomes enable those species to replicate their genomes faster and better adapt to new niches. Despite their prevalence, the mechanisms by which multipartite genomes are stably maintained are poorly understood.

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We investigate the influence of various optical fiber fabrication processes on the fluorescence decay of RE ions commonly used in fiber lasers and amplifiers, i.e. Yb, Tm and Ho.

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Bacterial species from diverse phyla contain multiple replicons, yet how these multipartite genomes are organized and segregated during the cell cycle remains poorly understood. has a 2.8-Mb circular chromosome (Ch1), a 2.

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Bacteria in the genus are important human and veterinary pathogens. The abortion and infertility they cause in food animals produce economic hardships in areas where the disease has not been controlled, and human brucellosis is one of the world's most common zoonoses. strains have also been isolated from wildlife, but we know much less about the pathobiology and epidemiology of these infections than we do about brucellosis in domestic animals.

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Members of the , often carry multiple secondary replicons in addition to the primary chromosome with compatible -based replication systems. Unlike secondary chromosomes and chromids, -based megaplasmids and plasmids can undergo copy number fluctuations and are capable of conjugative transfer in response to environmental signals. Several lineages harbor three secondary -based replicons, including a secondary chromosome (often linear), the Ti (tumor-inducing) plasmid and the At megaplasmid.

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Study Objectives: Text messaging (TM) may provide an inexpensive and convenient method for self-reported sleep assessment. This pilot study evaluated the feasibility of a TM sleep diary among a racial/ethnic minority population with uncontrolled type 2 diabetes.

Methods: A convenience sample of 40 participants with uncontrolled type 2 diabetes was recruited.

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Many life-saving drugs are still inaccessible and unaffordable in low- and middle-income countries, particularly in Sub-Saharan Africa. This contributes to poor health outcomes, wider health and socioeconomic inequities, and higher patient spending on healthcare. While resource limitations facing national regulatory authorities (NRAs) contribute to the problem, we believe that (1) fragmented and complex drug regulations, (2) suboptimal enforcement of existing regulations, and (3) poorly designed disincentives for non-compliance play a larger role.

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Bacteria with multi-replicon genome organizations, including members of the family , often carry a variety of niche-associated functions on large plasmids. While evidence exists for cross-replicon interactions and co-evolution between replicons in many of these systems, remarkable strain-to-strain variation is also observed for extrachromosomal elements, suggesting increased genetic plasticity. Here, we show that curing of the tumor-inducing virulence plasmid (pTi) of an octopine-type lineage leads to a large deletion in the co-resident At megaplasmid (pAt).

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From 2006 to 2014, Supply Chain Management System (SCMS), the global procurement and distribution project for the U.S. President's Emergency Plan for AIDS Relief (PEPFAR), distributed over US$1.

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Many important pathogens maintain significant populations in highly disparate disease and non-disease environments. The consequences of this environmental heterogeneity in shaping the ecological and evolutionary dynamics of these facultative pathogens are incompletely understood. Agrobacterium tumefaciens, the causative agent for crown gall disease of plants has proven a productive model for many aspects of interactions between pathogens and their hosts and with other microbes.

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During a trip to Cyprus, 27 September-4 October 2015, 4 specimens (3♂ and 1♀) of a Coleophora sp. unknown to the author were collected in the Oreites Forest, above Kouklia, Paphos District (N34 7307149: E32 6366901, altitude 340m). Two males and the one female were dissected.

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Senegal and other developing countries are improving access to health commodities by outsourcing supply chain logistics to private providers. To achieve broader, lasting reform, we must support further adoption of the outsourced model; assist country-led cost-benefit analyses; and help governments build capacity to manage contracts and overcome other barriers.

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As with many pathogenic bacteria, agrobacterial plant pathogens carry most of their virulence functions on a horizontally transmissible genetic element. The tumor-inducing (Ti) plasmid encodes the majority of virulence functions for the crown gall agent Agrobacterium tumefaciens. This includes the vir genes which drive genetic transformation of host cells and the catabolic genes needed to utilize the opines produced by infected plants.

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We describe the advantages of using diffractive (Fresnel) lenses on thin membranes over conventional optics for, among others, future space telescope projects. Fabrication methods are presented for lenses on two types of freestanding membrane up to 50 cm in size. The first is a Fresnel lens etched into a thin (380-microm) glass sheet, and the second is an approximately 50-microm-thick polymer membrane containing a Fresnel lens made by replication process from a specially made fused-silica master.

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Space-invariant, multilevel, diffractive phase elements are designed for large-scale pattern-formation tasks. The importance of the design algorithm and the phase-encoding geometry of the diffractive element is discussed with regard to the performance of both on- and off-axis reconstruction, notably for pixelated gratings. A new phase-encoding scheme is presented that results in an increase of the diffraction efficiency for the off-axis case.

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We report what we believe to be the first applications of numerical optimization algorithms to the design of diffractive elements that customize the fundamental mode profile of a laser system. Standard design techniques treat these elements as specific phase-conjugation devices, which leads to performance loss when they are quantized to permit fabrication. Numerical optimization can account for quantization of the element to increase the effective performance.

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A diffractive Alvarez lens is demonstrated that consists of two separate phase plates, each having complementary 16-level surface-relief profiles that contain cubic phase delays. Translation of these two components in the plane of the phase plates is shown to produce a variable astigmatic focus. Both spherical and cylindrical phase profiles are demonstrated with good accuracy, and the discrete surface-relief features are shown to cause less than lambda/10 wave-front aberration in the transmitted wave front over a 40 mm x 80 mm region.

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Unlabelled: This posthoc analysis of four trials studied the efficacy of risedronate to reduce fragility fractures in postmenopausal women with osteopenia (i.e., T-scores between -1 and -2.

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