Publications by authors named "George Michael"

Introduction: Greater body mass index (BMI) has been associated with less radiographic progression in rheumatoid arthritis (RA). We evaluated the association between BMI and joint damage progression as measured by X-ray and MRI.

Methods: 1068 subjects with RA from two clinical trials of golimumab (GO-BEFORE and GO-FORWARD) had radiographs performed at weeks 0, 52 and 104 and evaluated using the van der Heijde-Sharp (vdHS) scoring system.

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Automated patch clamp devices are now commonly used for studying ion channels. A useful modification of this approach is the replacement of the glass pipet with a thin planar glass layer with a small hole in the middle. Planar patch clamp devices, such as the three described in this unit, are overtaking glass pipets in popularity because they increase throughput, are easier to use, provide for the acquisition of high-quality and information-rich data, and allow for rapid perfusion and temperature control.

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Visual attention has been shown to progress from the most to the least salient item in a given scene. Cognitive and physiological models assume that this orienting of covert attention relies on the collicular pathway, involving the superior colliculus and the pulvinar. Recent studies questioned this statement as they described attentional capture by visual items invisible to the superior colliculus.

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Carbon-hydrogen bond activation reactions of four cycloalkanes (C5H10, C6H12, C7H14, and C8H16) by the Cp'Rh(CO) fragments (Cp' = η(5)-C5H5 (Cp) or η(5)-C5Me5 (Cp*)) were modeled theoretically by combining density functional and coupled cluster theories, and their reaction rates were measured by fast time-resolved infrared spectroscopy. The reaction has two steps, starting with the formation of a σ-complex intermediate, followed by oxidative addition of the C-H bond by the rhodium. A range of σ-complex stabilities among the electronically unique C-H bonds in a cycloalkane were calculated and are related to the individual strengths of the C-H bond's interactions with the Rh fragment and the steric repulsion that is incurred upon forming the specific σ-complex.

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Photoproduction of dihydrogen (H2) by a low molecular weight analogue of the active site of [NiFe] hydrogenase has been investigated by reduction of the [NiFe2] cluster, 1, by a photosensitier PS (PS = [ReCl(CO)3(bpy)] or [Ru(bpy)3][PF6]2). Reductive quenching of the (3)MLCT excited state of the photosensitizer by NEt3 or N(CH2CH2OH)3 (TEOA) generates PS(•-), and subsequent intermolecular electron transfer to 1 produces the reduced anionic form of 1. Time-resolved infrared spectroscopy (TRIR) has been used to probe the intermediates throughout the reduction of 1 and subsequent photocatalytic H2 production from [HTEOA][BF4], which was monitored by gas chromatography.

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Purpose Of Review: This review describes the impact of HIV infection on gut-associated lymphoid tissue, the mechanisms for persistent gut-associated lymphoid tissue dysfunction despite effective antiretroviral therapy, and potential strategies to restore gut-associated lymphoid tissue function and promote immune reconstitution.

Recent Findings: Recent studies indicate that unresolved microbial translocation and intestinal dysbiosis may continue to promote enteropathy as well as HIV-associated and non-HIV-associated conditions in many HIV patients who otherwise maintain therapeutic control of systemic viral replication.

Summary: Several novel therapeutic approaches to reduce intestinal inflammation and mitigate microbial translocation may hold promise for restoring gastrointestinal health and thereby increasing the efficacy of immune reconstitution in HIV-infected patients undergoing antiretroviral therapy.

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Unlabelled: Epithelial barrier dysfunction during human immunodeficiency virus (HIV) infection has largely been attributed to the rapid and severe depletion of CD4(+) T cells in the gastrointestinal (GI) tract. Although it is known that changes in mucosal gene expression contribute to intestinal enteropathy, the role of small noncoding RNAs, specifically microRNA (miRNA), has not been investigated. Using the simian immunodeficiency virus (SIV)-infected nonhuman primate model of HIV pathogenesis, we investigated the effect of viral infection on miRNA expression in intestinal mucosa.

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The design for a new high-pressure-low-temperature infrared (IR) cell for performing experiments using conventional Fourier transform infrared or fast laser-based time-resolved infrared spectroscopy, in a range of solvents, is described. The design builds upon a commercially available compressor and cold end (Polycold PCC(®) and CryoTiger(®)), which enables almost vibration-free operation, ideal for use with sensitive instrumentation. The design of our cell and cryostat allows for the study of systems at temperatures from 77 to 310 K and at pressures up to 250 bar.

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The solid-state, low-temperature linkage isomerism in a series of five square planar group 10 phosphino nitro complexes have been investigated by a combination of photocrystallographic experiments, Raman spectroscopy and computer modelling. The factors influencing the reversible solid-state interconversion between the nitro and nitrito structural isomers have also been investigated, providing insight into the dynamics of this process. The cis-[Ni(dcpe)(NO2)2] (1) and cis-[Ni(dppe)(NO2)2] (2) complexes show reversible 100 % interconversion between the η(1)-NO2 nitro isomer and the η(1)-ONO nitrito form when single-crystals are irradiated with 400 nm light at 100 K.

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Objectives: Vocal process granulomas (VPGs) are benign laryngeal lesions with controversial treatment and a tendency to recur. There are several treatment options with unpredictable results, high recurrence rates, and disappointing long-term outcome. The aims of this article are to focus on evidence-based current treatment strategies for primary lesions and recurrences.

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Despite sleep-induced drastic decrease of self-awareness, human sleep allows some cognitive processing of external stimuli. Here we report the fortuitous observation in a patient who, while being recorded with intra-cerebral electrodes, was able, during paradoxical sleep, to reproduce a motor behaviour previously performed at wake to consciously indicate her perception of nociceptive stimulation. Noxious stimuli induced behavioural responses only if they reached the cortex during periods when mid-frontal networks (pre-SMA, pre-motor cortex) were pre-activated.

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The mucosa that lines the respiratory and gastrointestinal (GI) tracts is an important portal of entry for pathogens and provides the first line of innate immune defense against infections. Although an abundance of memory CD4(+) T cells at mucosal sites render them highly susceptible to HIV infection, the gut and not the lung experiences severe and sustained CD4(+) T cell depletion and tissue disruption. We hypothesized that distinct immune responses in the lung and gut during the primary and chronic stages of viral infection contribute to these differences.

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Movement is known to attenuate the perception of tactile stimuli delivered on the moving part of the body, and this gating diminishes the greater the distance from the moving part. However, does it influence the perception of sensations occurring spontaneously without external triggers? In Experiment 1, participants were asked to focus on one hand while moving or not moving their thumb, and thereafter to map and describe the spatial and qualitative attributes of sensations perceived over the remaining, motionless part of the hand. The results show that movement reduces the frequency, spatial extent, and intensity of sensations, but also participants' confidence about their spatial characteristics.

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A series of dipyrido[3,2-a:2',3'-c]phenazine (dppz)-based ligands with electron-withdrawing substituents and their [Re(CO)3(L)Cl] and [Re(CO)3(L)(py)]PF6 complexes have been studied using Raman, resonance Raman, and transient resonance Raman (TR(2)) and time-resolved infrared (TRIR) spectroscopic techinques in conjunction with computational chemistry as well as electrochemical studies, emission, and absorption of ground and excited states. DFT (B3LYP) frequency calculations show good agreement with nonresonant Raman spectra, which allowed these to be used to identify phenanthroline, phenazine, and delocalized modes. These band assignments were used to establish the nature of chromophores active in resonance Raman spectra, probed with wavelengths between 350.

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The mechanism and intermediates in the UV-light-initiated ligand rearrangement of fac-Re(diimine)(CO)3Cl to form the mer isomer, when incorporated into a 3D metal-organic framework (MOF), have been investigated. The structure hosting the rhenium diimine complex is a 3D network with the formula {Mn(DMF)2[LRe(CO)3Cl]}∞ (ReMn; DMF = N,N-dimethylformamide), where the diimine ligand L, 2,2'-bipyridine-5,5'-dicarboxylate, acts as a strut of the MOF. The incorporation of ReMn into a KBr disk allows spatial distribution of the mer-isomer photoproduct in the disk to be mapped and spectroscopically characterized by both Fourier transform infrared and Raman microscopy.

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Interleukin-22 (IL-22) is highly induced in response to infections with a variety of pathogens, and its main functions are considered to be tissue repair and host defense at mucosal surfaces. Here we showed that IL-22 has a unique role during infection in that its expression suppressed the intestinal microbiota and enhanced the colonization of a pathogen. IL-22 induced the expression of antimicrobial proteins, including lipocalin-2 and calprotectin, which sequester essential metal ions from microbes.

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More efficient models are needed to assess potential carcinogenicity hazard of environmental chemicals based on early events in tumorigenesis. Here, we investigated time course profiles for key events in an established cancer mode of action. Using a case study approach, we evaluated two reference phthalates, di(2-ethylhexyl) phthalate (DEHP) and its stereoisomer di-n-octyl phthalate (DNOP), across the span of a two-year carcinogenicity bioassay.

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Space travel presents unlimited opportunities for exploration and discovery, but requires better understanding of the biological consequences of long-term exposure to spaceflight. Immune function in particular is relevant for space travel. Human immune responses are weakened in space, with increased vulnerability to opportunistic infections and immune-related conditions.

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The donor-acceptor ligands 11-(4-diphenylaminophenyl)dipyrido[3,2-a:2',3'-c]phenazine (dppz-PhNPh2) and 11-(4-dimethylaminophenyl)dipyrido[3,2-a:2',3'-c]phenazine (dppz-PhNMe2), and their rhenium complexes, [Re(CO)3X] (X = Cl(-), py, 4-dimethylaminopyridine (dmap)), are reported. Crystal structures of the two ligands were obtained. The optical properties of the ligands and complexes are dominated by intraligand charge transfer (ILCT) transitions from the amine to the dppz moieties with λabs = 463 nm (ε = 13 100 M(-1) cm(-1)) for dppz-PhNMe2 and with λabs = 457 nm (ε = 16 900 M(-1) cm(-1)) for dppz-PhNPh2.

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Cognitive and neural models have proposed the existence of a single inhibitory process that regulates behavior and depends on the right frontal operculum (rFO). The aim of this study was to make a contribution to the ongoing debate as to whether inhibition is a single process or is composed of multiple, independent processes. Here, within a single paradigm, we assessed the links between two inhibitory phenomena-namely, resistance to involuntary visual capture by abrupt onsets and resolving of spatial stimulus-response conflict.

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Objective: American College of Rheumatology and European League Against Rheumatism guidelines recommend colchicine to prevent gout flares in patients initiating and increasing uric acid–lowering therapy until serum uric acid is maintained at ≤6 mg/dl. We aimed to evaluate how well colchicine prescribing practices adhere to these guidelines and to examine factors associated with improved prescribing.

Methods: Electronic medical records were reviewed for 126 patients with active colchicine prescriptions for prophylaxis of gout flares.

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A majority of individuals infected with human immunodeficiency virus (HIV) have inadequate access to antiretroviral therapy and ultimately develop debilitating oral infections that often correlate with disease progression. Due to the impracticalities of conducting host-microbe systems-based studies in HIV infected patients, we have evaluated the potential of simian immunodeficiency virus (SIV) infected rhesus macaques to serve as a non-human primate model for oral manifestations of HIV disease. We present the first description of the rhesus macaque oral microbiota and show that a mixture of human commensal bacteria and "macaque versions" of human commensals colonize the tongue dorsum and dental plaque.

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Objective: Deficits in multiple aspects of attention are a hallmark of the cognitive impairments found with neurofibromatosis type I (NF1). Given, however, that some attention components are hierarchically organized, it is possible that sustained attention, flexibility, and resistance to interference deficits observed in NF1 may be because of weakened lower order attention components. This study investigated the state of these low-level components in NF1.

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Objectives: There is some discrepancy in the results regarding emotional enhancement of memory (EEM) in Alzheimer's disease (AD). Some studies report better retrieval of emotional information, especially positive, than neutral information. This observation is similar to the positivity effect reported in healthy older adults.

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The viability of applying bodipy sensitisers to NiO-based p-type dye-sensitised solar cells (p-DSCs) has been successfully demonstrated. The triphenylamine donor-bodipy acceptor design promotes a long-lived charge-separated state which is difficult to achieve with NiO-based devices. The current was above 3 mA cm(-2) and the IPCE was 28%.

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