148 results on '"R. Mathieson"'
Search Results
2. Subjective loss of clinical response to TNFi in axSpA relates to recurrence of MRI bone marrow oedema particularly with long-acting agents
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Stephanie R Harrison, Noemi Busquets-Pérez, Dennis McGonagle, Helena Marzo-Ortega, Hannah R. Mathieson, M. Merashli, and Rebecca Ansell
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Adult ,Male ,medicine.medical_specialty ,Bone marrow oedema ,Etanercept ,Rheumatology ,Bone Marrow ,Internal medicine ,Statistical significance ,Adalimumab ,Edema ,Humans ,Medicine ,Pharmacology (medical) ,Bone Marrow Diseases ,BASDAI ,Ankylosing spondylitis ,medicine.diagnostic_test ,Tumor Necrosis Factor-alpha ,business.industry ,Magnetic resonance imaging ,medicine.disease ,Magnetic Resonance Imaging ,Infliximab ,Female ,business ,Axial Spondyloarthritis ,medicine.drug - Abstract
Objectives Subjective loss of response immediately prior to routine TNFi therapy can occur in axial spondyloarthritis (axSpA). We investigated clinical outcomes in patients taking the first three licenced TNFis and correlated this with recurrence of MRI bone marrow oedema (MRI-BMO). Methods Proof-of-concept study including axSpA patients established on etanercept (ETA), adalimumab (ADA) or infliximab (IFX) reporting symptom deterioration prior to next dose. MRI/clinical data were collected prior to scheduled dose (v1), 4 days post-dose (v2) and at the time of patient-reported symptom return (v3). MRI spine/sacroiliac joints utilizing 3 T were scored using the semi-quantitative Leeds MRI scoring system. Results A total of 113 clinical assessments and MRIs were performed in 38 participants (ADA = 16, ETA = 12, IFX = 10), mean age 42.1 years ± 24.4(2SD, n = 38), 71.1% male (n = 27/38), 69.7% HLA-B27 positive (n = 23/33). At v1, all patients had high disease activity [ASDAS-CRP = 3 (2.7–3.7)] and 57.9% had MRI-BMO (number of MRI-BMO: ETA = 26, ADA = 59, IFX = 28). Improved clinical responses were seen at v2 [ASDAS-CRP −0.41(−0.81 − 0.30), P =0.018; BASDAI −0.58(−2.2 − 0.52), P =0.024]. Despite just a 4-day interval between v1 and v2, a numerical reduction in MRI-BMO lesions between v1/v2 was observed (ETA = −6, ADA = −10, IFX = −3). By v3, comparatively fewer new BMO lesions were detected in the ETA and ADA groups compared with IFX (ETA = −1, ADA = +3, IFX = +8), although the numbers were too small to enable testing for statistical significance. Conclusions Short-lived fluctuations in MRI-BMO were commoner with longer-acting agents and corresponded with subjective loss of clinical response before next scheduled TNFi dose. Larger studies are needed to confirm the possible pathogenic implications of this phenomenon.
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- 2021
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3. Neonatal EEG graded for severity of background abnormalities in hypoxic-ischaemic encephalopathy
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John M. O’Toole, Sean R. Mathieson, Sumit A. Raurale, Fabio Magarelli, William P. Marnane, Gordon Lightbody, and Geraldine B. Boylan
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Statistics and Probability ,Signal Processing (eess.SP) ,FOS: Computer and information sciences ,Computer Science - Machine Learning ,FOS: Physical sciences ,Library and Information Sciences ,Physics - Medical Physics ,Computer Science Applications ,Education ,Machine Learning (cs.LG) ,FOS: Electrical engineering, electronic engineering, information engineering ,Medical Physics (physics.med-ph) ,Statistics, Probability and Uncertainty ,Electrical Engineering and Systems Science - Signal Processing ,Information Systems - Abstract
This report describes a set of neonatal electroencephalogram (EEG) recordings graded according to the severity of abnormalities in the background pattern. The dataset consists of 169 hours of multichannel EEG from 53 neonates recorded in a neonatal intensive care unit. All neonates received a diagnosis of hypoxic-ischaemic encephalopathy (HIE), the most common cause of brain injury in full term infants. For each neonate, multiple 1-hour epochs of good quality EEG were selected and then graded for background abnormalities. The grading system assesses EEG attributes such as amplitude, continuity, sleep–wake cycling, symmetry and synchrony, and abnormal waveforms. Background severity was then categorised into 4 grades: normal or mildly abnormal EEG, moderately abnormal EEG, majorly abnormal EEG, and inactive EEG. The data can be used as a reference set of multi-channel EEG for neonates with HIE, for EEG training purposes, or for developing and evaluating automated grading algorithms.
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- 2022
4. Intentional Stranding by Mammal-Hunting Killer Whales (Orcinus orca) in the Salish Sea
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Josh P. Tawse, Justine N. Buckmaster, Chelsea R. Mathieson, Kelsey D. Cullen, and Josh D. McInnes
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Fishery ,Geography ,Animal Science and Zoology ,Mammal ,Aquatic Science ,Nature and Landscape Conservation - Published
- 2020
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5. Sleep state organisation of moderate to late preterm infants in the neonatal unit
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Mary Anne J, Ryan, Sean R, Mathieson, Vicki, Livingstone, Marc Paul, O'Sullivan, Eugene M, Dempsey, and Geraldine B, Boylan
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Sleep supports neurodevelopment and sleep architecture reflects brain maturation. This prospective observational study describes the nocturnal sleep architecture of healthy moderate to late preterm (MLP) infants in the neonatal unit at 36 weeks post menstrual age (PMA).MLP infants, in the neonatal unit of a tertiary hospital in Ireland from 2017 to 2018, had overnight continuous electroencephalography (cEEG) with video for a minimum 12 h at 36 weeks PMA. The total sleep time (TST) including periods of active sleep (AS), quiet sleep (QS), indeterminate sleep (IS), wakefulness and feeding were identified, annotated and quantified.A total of 98 infants had cEEG with video monitoring suitable for analysis. The median (IQR) of TST in the 12 h period was 7.09 h (IQR 6.61-7.76 h), 4.58 h (3.69-5.09 h) in AS, 2.02 h (1.76-2.36 h) in QS and 0.65 h (0.48-0.89 h) in IS. The total duration of AS was significantly lower in infants born at lower GA (p = 0.007) whilst the duration of individual QS periods was significantly higher (p = 0.001).Overnight cEEG with video at 36 weeks PMA showed that sleep state architecture is dependent on birth GA. Infants with a lower birth GA have less AS and more QS that may have implications for later neurodevelopment.EEG provides objective information about the sleep organisation of the moderate to late preterm (MLP) infant. Quantitative changes in sleep states occur with each week of advancing gestational age (GA). Active sleep (AS) is the dominant sleep state that was significantly lower in infants born at lower GA. MLP infants who were exclusively fed orally had a shorter total sleep time and less AS compared to infants who were fed via nasogastric tube.
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- 2022
6. Development of an Eeg Artefact Detection Algorithm and its Application in Grading Hypoxic-Ischemic Encephalopathy
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Mark E. O'Sullivan, Gordon Lightbody, Sean R. Mathieson, William P. Marnane, Geraldine Boylan, and John M. O'Toole
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- 2022
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7. Tracé alternant detector for grading hypoxic-ischemic encephalopathy in neonatal EEG
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Sumit A. Raurale, Geraldine B. Boylan, Sean R. Mathieson, William P. Marnane, Gordon Lightbody, and John M. O'Toole
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- 2021
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8. Evidence of a sudden increase in the nuclear size of proton-rich silver-96
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R. F. Garcia Ruiz, A. Zadvornaya, M. Hukkanen, L. Al Ayoubi, Bradley Cheal, K. Chrysalidis, R. Mathieson, P. Imgram, A. de Roubin, Iain Moore, L. Canete, Mark Bissell, Anu Kankainen, Ilkka Pohjalainen, Tommi Eronen, S. Geldhof, C. S. Devlin, S. Kujanpää, Á. Koszorús, Markus Kortelainen, C. Delafosse, Dmitrii Nesterenko, M. Reponen, Paul Campbell, R. P. de Groote, M. Vilen, O. Beliuskina, W. Gins, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), and Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
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CHARGE RADII ,EFFICIENCY ,Proton ,Science ,SYMMETRY ,Nuclear Theory ,General Physics and Astronomy ,IONIZATION SPECTROSCOPY ,[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex] ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,Effective nuclear charge ,Article ,Nuclear physics ,Charge radius ,MOMENTS ,0103 physical sciences ,experimental nuclear physics ,Neutron ,Nuclear Physics - Experiment ,Physics::Atomic Physics ,BETA-DECAY ,Experimental nuclear physics ,010306 general physics ,LASER SPECTROSCOPY ,Nuclear Experiment ,Physics ,RESONANCE IONIZATION ,isotoopit ,Multidisciplinary ,Science & Technology ,Isotope ,010308 nuclear & particles physics ,General Chemistry ,Radius ,ION-SOURCE ,Multidisciplinary Sciences ,Theoretical nuclear physics ,Neutron number ,theoretical nuclear physics ,Science & Technology - Other Topics ,ISOTOPES ,Density functional theory ,ydinfysiikka - Abstract
Understanding the evolution of the nuclear charge radius is one of the long-standing challenges for nuclear theory. Recently, density functional theory calculations utilizing Fayans functionals have successfully reproduced the charge radii of a variety of exotic isotopes. However, difficulties in the isotope production have hindered testing these models in the immediate region of the nuclear chart below the heaviest self-conjugate doubly-magic nucleus 100Sn, where the near-equal number of protons (Z) and neutrons (N) lead to enhanced neutron-proton pairing. Here, we present an optical excursion into this region by crossing the N = 50 magic neutron number in the silver isotopic chain with the measurement of the charge radius of 96Ag (N = 49). The results provide a challenge for nuclear theory: calculations are unable to reproduce the pronounced discontinuity in the charge radii as one moves below N = 50. The technical advancements in this work open the N = Z region below 100Sn for further optical studies, which will lead to more comprehensive input for nuclear theory development., Laser spectroscopic measurements of isotopes near the doubly-magic 100-Sn are challenging due to difficulties in their production. Here the authors measure the ground state charge radius of the proton-rich 96-Ag isotope and find a discontinuity in the nuclear size when crossing the neutron number N equal to 50.
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- 2021
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9. Case Report: Early Neonatal EEG in Two Infants with Pallister Killian Syndrome (PKS)
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Carol M Stephens, Andreea M Pavel, Sean R Mathieson, Niamh McSweeney, Brian McNamara, Michael Moore, and Geraldine B Boylan
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polycyclic compounds ,General Medicine - Abstract
Pallister Killian Syndrome (PKS) is a rare genetic disorder caused by a mosaic tetrasomy of the short arm of chromosome 12. The syndrome is characterised by typical craniofacial dysmorphism, congenital anomalies and intellectual disability. Epilepsy is a known complication, with onset usually occurring in early childhood and characterised most commonly by spasms and myoclonic seizures. To the best of our knowledge, there have been no cases describing the early neonatal EEG in PKS and electrographic seizures, to date. Here, we report two cases of PKS presenting in the neonatal period with distinctive EEG features and seizures.
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- 2022
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10. Combined inhibition of tumour necrosis factor-alpha and interleukin-12/23 for long-standing, refractory psoriatic disease: a differential role for cytokine pathways?
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Dennis McGonagle, Conor Magee, Helena Marzo-Ortega, Gabriele De Marco, Mark Goodfield, Mira Merashli, Oliver FitzGerald, and Hannah R. Mathieson
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0301 basic medicine ,business.industry ,medicine.medical_treatment ,Arthritis ,Psoriatic disease ,Tumour necrosis factor alpha ,medicine.disease ,03 medical and health sciences ,030104 developmental biology ,Pharmacotherapy ,Cytokine ,Rheumatology ,Refractory ,Cytokines metabolism ,Cancer research ,Interleukin 12 ,medicine ,Pharmacology (medical) ,business - Published
- 2018
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11. Diagnosis of seizures and encephalopathy using conventional EEG and amplitude integrated EEG
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Geraldine B, Boylan, Liudmila, Kharoshankaya, and Sean R, Mathieson
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Adult ,Brain Diseases ,Hypothermia, Induced ,Pregnancy ,Seizures ,Hypoxia-Ischemia, Brain ,Infant, Newborn ,Humans ,Electroencephalography ,Female - Abstract
Seizures are more common in the neonatal period than at any other time of life, partly due to the relative hyperexcitability of the neonatal brain. Brain monitoring of sick neonates in the NICU using either conventional electroencephalography or amplitude integrated EEG is essential to accurately detect seizures. Treatment of seizures is important, as evidence increasingly indicates that seizures damage the brain in addition to that caused by the underlying etiology. Prompt treatment has been shown to reduce seizure burden with the potential to ameliorate seizure-mediated damage. Neonatal encephalopathy most commonly caused by a hypoxia-ischemia results in an alteration of mental status and problems such as seizures, hypotonia, apnea, and feeding difficulties. Confirmation of encephalopathy with EEG monitoring can act as an important adjunct to other investigations and the clinical examination, particularly when considering treatment strategies such as therapeutic hypothermia. Brain monitoring also provides useful early prognostic indicators to clinicians. Recent use of machine learning in algorithms to continuously monitor the neonatal EEG, detect seizures, and grade encephalopathy offers the exciting prospect of real-time decision support in the NICU in the very near future.
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- 2019
12. Retrospective evaluation of a clinical decision support tool for effective computed tomography angiography utilization in urgent brain imaging of suspected TIA/minor stroke in the emergency department
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Brian Farrell, Kristine Votova, Colin Sedgwick, Devin R. Harris, Maximilian B Bibok, Robert Balshaw, Andrew M. Penn, John R Mathieson, Madeline Nealis, Mary Lesperance, and Melanie Penn
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Male ,medicine.medical_specialty ,Computed Tomography Angiography ,Clinical decision support system ,Sensitivity and Specificity ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,cardiovascular diseases ,030212 general & internal medicine ,Stroke ,Computed tomography angiography ,Aged ,Retrospective Studies ,Transient ischemic attack (TIA) ,medicine.diagnostic_test ,business.industry ,Brain ,030208 emergency & critical care medicine ,Retrospective cohort study ,Emergency department ,Guideline ,medicine.disease ,Decision Support Systems, Clinical ,Ischemic Attack, Transient ,Radiological weapon ,Emergency medicine ,Emergency Medicine ,Female ,business ,Emergency Service, Hospital - Abstract
ObjectivesThe Canadian Stroke Best Practice Recommendations suggests that patients suspected of transient ischemic attack (TIA)/minor stroke receive urgent brain imaging, preferably computed tomography angiography (CTA). Yet, high requisition rates for non-cerebrovascular patients overburden limited radiological resources, putting patients at risk. We hypothesize that our clinical decision support tool (CDST) developed for risk stratification of TIA in the emergency department (ED), and which incorporates Canadian guidelines, could improve CTA utilization.MethodsRetrospective study design with clinical information gathered from ED patient referrals to an outpatient TIA unit in Victoria, BC, from 2015-2016. Actual CTA orders by ED and TIA unit staff were compared to hypothetical CTA ordering if our CDST had been used in the ED upon patient arrival.ResultsFor 1,679 referrals, clinicians ordered 954 CTAs. Our CDST would have ordered a total of 977 CTAs for these patients. Overall, this would have increased the number of imaged-TIA patients by 89 (10.1%) while imaging 98 (16.1%) fewer non-cerebrovascular patients over the 2-year period. Our CDST would have ordered CTA for 18 (78.3%) of the recurrent stroke patients in the sample.ConclusionsOur CDST could enhance CTA utilization in the ED for suspected TIA patients, and facilitate guideline-based stroke care. Use of our CDST would increase the number of TIA patients receiving CTA before ED discharge (rather than later at TIA units) and reduce the burden of imaging stroke mimics in radiological departments.
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- 2018
13. Interaction of Taste and Place Coding in the Hippocampus
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Donald B. Katz, Elon R. Mathieson, Shantanu P. Jadhav, Seneca J. Scott, Linnea E Herzog, and Leila May Pascual
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0301 basic medicine ,Male ,Taste ,Lateral hypothalamus ,Context-dependent memory ,Hippocampus ,Action Potentials ,Context (language use) ,Sensory system ,Hippocampal formation ,Amygdala ,03 medical and health sciences ,0302 clinical medicine ,Memory ,medicine ,Animals ,Rats, Long-Evans ,Palatability ,Research Articles ,030304 developmental biology ,Neurons ,0303 health sciences ,General Neuroscience ,Taste Perception ,Rats ,030104 developmental biology ,medicine.anatomical_structure ,nervous system ,Space Perception ,Psychology ,Neuroscience ,030217 neurology & neurosurgery - Abstract
An animal’s survival depends on finding food, and the memory of food and contexts are often linked. Given that the hippocampus is required for spatial and contextual memory, it is reasonable to expect related coding of space and food stimuli in hippocampal neurons. However, relatively little is known about how the hippocampus responds to tastes, the most central sensory property of food. In this study, we examined the taste-evoked responses and spatial firing properties of single units in the dorsal CA1 hippocampal region as male rats received a battery of taste stimuli differing in both chemical composition and palatability within a specific spatial context. We identified a subset of hippocampal neurons that responded to tastes, some of which were place cells. These taste and place responses had a distinct interaction: taste-responsive cells tended to have less spatially specific firing fields, and place cells only responded to tastes delivered inside their place field. Like neurons in the amygdala and lateral hypothalamus, hippocampal neurons discriminated between tastes predominantly on the basis of palatability, with taste-selectivity emerging concurrently with palatability-relatedness; these responses did not reflect movement or arousal. However, hippocampal taste responses emerged several hundred msec later than responses in other parts of the taste system, suggesting that the hippocampus does not influence real-time taste decisions, instead associating the hedonic value of tastes with a particular context. This incorporation of taste responses into existing hippocampal maps could be one way that animals use past experience to locate food sources.Significance statementFinding food is essential for animals’ survival, and taste and context memory are often linked. While hippocampal responses to space and contexts have been well characterized, little is known about how the hippocampus responds to tastes. Here, we identified a subset of hippocampal neurons that discriminated between tastes based on palatability. Cells with stronger taste responses typically had weaker spatial responses, and taste responses were confined to place cells’ firing fields. Hippocampal taste responses emerged later than in other parts of the taste system, suggesting that the hippocampus does not influence taste decisions, but rather, associates the hedonic value of tastes consumed within a particular context. This could be one way that animals use past experience to locate food sources.
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- 2018
14. Assessment of two screening tools to identify psoriatic arthritis in patients with psoriasis
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Philip M. Laws, Laura C. Coates, Hector Chinoy, Hannah R. Mathieson, Richard B. Warren, Laura Savage, Dennis McGonagle, F Mahmood, C R Lovell, E. Korendowych, P S Helliwell, and Robin Waxman
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Adult ,Male ,medicine.medical_specialty ,Cross-sectional study ,diagnosis ,Arthritis ,Physical examination ,Dermatology ,CONTEST ,030207 dermatology & venereal diseases ,03 medical and health sciences ,Psoriatic arthritis ,0302 clinical medicine ,Quality of life ,Internal medicine ,Psoriasis ,Surveys and Questionnaires ,medicine ,Humans ,Mass Screening ,Physical Examination ,030203 arthritis & rheumatology ,psoriatic arthritis ,Receiver operating characteristic ,medicine.diagnostic_test ,business.industry ,screening ,Arthritis, Psoriatic ,psoriasis ,Middle Aged ,medicine.disease ,Infectious Diseases ,Cross-Sectional Studies ,ROC Curve ,Area Under Curve ,Quality of Life ,Female ,business - Abstract
Background: Many patients with psoriasis have undiagnosed psoriatic arthritis. Low specificity is found with many PsA screening tools. A new instrument, the CONTEST questionnaire, was developed utilizing the most discriminative items from existing instruments.Objective: The aim of this study was to compare the CONTEST and PEST screening tools.Methods: People attending secondary care clinics with psoriasis, but not PsA, completed the questionnaires, were assessed for function and quality of life, and had a physical examination. Patients thought to have PsA were compared to those without. The performance of CONTEST and PEST was compared using area under the receiver operating curve (AUC), and sensitivity and specificity at the previously published cut‐offs.Results: A total of 451 dermatology patients were approached, 35% were reviewed and 27 (17%, 95% CI 12.3–21.7) had unidentified psoriatic arthritis. The sensitivity and specificity (95% CI) of PEST were 0.60 (0.42–0.78)/0.76 (0.69–0.83) and for CONTEST 0.53 (0.34–0.72)/0.71 (0.63–0.79). The confidence limits for the AUC overlapped (AUC for PEST 0.72 (0.61–0.84), for CONTEST 0.66 (0.54–0.77).Conclusions: PEST and CONTEST questionnaires performed equally well, with no superiority of the new CONTEST tool.
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- 2018
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15. THU0368 Clinical and imaging characteristics of patients with axial spondyloarthritis reporting flare symptoms immediately prior to next dose in routine tnfi therapy
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Hannah R. Mathieson, Helena Marzo-Ortega, D. McGonagle, Noemi Busquets-Pérez, R Ansell, and Mira Merashli
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medicine.medical_specialty ,Scoring system ,business.industry ,Infliximab ,Etanercept ,Lesion ,Statistical significance ,medicine ,Adalimumab ,Radiology ,medicine.symptom ,Axial spondyloarthritis ,business ,Active inflammation ,medicine.drug - Abstract
Background Tumour necrosis factor inhibitors (TNFi) are highly efficacious in axial spondyloarthritis (axSpA) with significant clinical responses mirrored in resolution of MRI determined bone marrow oedema (BMO) lesions representative of active inflammation in the sacroiliac joints (SIJ) and spine. However, symptom flare suggesting loss of response is common with many patients reporting deterioration days or weeks prior to the next dose. We hypothesised that intermittent suppression of inflammation with longer acting TNFis such as adalimumab or infliximab may be associated with a greater likelihood of recurrence of MRI determined BMO lesions than shorter acting agents such as etanercept. Objectives To explore the relationship between symptom flare immediately prior to next treatment dose and recurrence of MRI determined BMO lesions with different TNFi in axSpA. Methods Proof-of-concept, single centre study. Eligible participants were adults with axSpA established on adalimumab, etanercept or infliximab describing loss of response immediately prior to next treatment dose. Loss of response was defined as subjective “flare” or “wearing off” of drug effect before the expected duration of treatment effect. Participants attended at three points: Baseline: first day of treatment cycle (day of drug dose); Endpoint 1: 3–4 days after dose; and Endpoint 2: within 48 hours of next dose. ASDAS-CRP and whole spine and SIJ MR imaging utilising 3T MRI scanner were performed at each visit. Images were scored according to the semi-quantitative Leeds MRI scoring system by two observers blinded to participant identity and date of scan. Results 38 participants (16 adalimumab; 12 etanercept; 10 infliximab) with a total 113 MRI scans were analysed. 71% (n=27) male; 60% (n=23) HLA-B27+ with no differences between the groups; 73.7% (n=28) fulfilled mNYC for AS; the remainder were classified as nr-axSpA. 58% (n=22) had at least 1 Grade 1 BMO lesion at baseline with lesions more commonly seen with longer acting drugs (5/12 in etanercept group; 9/16 in adalimumab group; 8/10 in infliximab group) and 11 (50%) had at least 1 Grade ≥2 lesion (Table 2). There was a trend towards number and severity of BMO lesions fluctuating through the treatment cycle (Figure 1) mimicking subjective loss of response, also reflected on the ASDAS-CRP (Table 1) but this did not reach statistical significance. Conclusions This small proof-of-concept study shows subtle fluctuations on MRI changes of BMO and ASDAS-CRP corresponding to time of subjective “flare” before next scheduled TNFi dose in subjects with axSpA. Although these changes may be more common with the longer acting TNFi our data are not confirmatory. Larger studies are required to explore this concept further as these observations are potentially relevant for disease progression since cycles of inflammation and its subsequent suppression could theoretically increase the risk of new bone formation. Acknowledgements This study was sponsored by Pfizer. Disclosure of Interest R. Ansell Grant/research support from: Pfizer, H. Mathieson: None declared, M. Merashli: None declared, N. Busquets-Perez: None declared, D. McGonagle Grant/research support from: Celgene, Janssen & Pfizer, Consultant for: AbbVie, Celgene, Janssen, Novartis, UCB, Speakers bureau: Abbvie, Celgene, Janssen, UCB., H. Marzo-Ortega Grant/research support from: Janssen & Pfizer., Consultant for: AbbVie, Celgene, Janssen, Novartis, UCB. S, Speakers bureau: Abbvie, Celgene, Janssen, UCB.
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- 2017
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16. Diurnal variation of gait in patients with rheumatoid arthritis: The DIVIGN study☆
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Hannah R. Mathieson, Lucy Edgson, Philip S. Helliwell, Anthony C. Redmond, Michael R. Backhouse, David Pickles, and Paul Emery
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musculoskeletal diseases ,Adult ,Male ,medicine.medical_specialty ,Biophysics ,Poison control ,Walking ,Article ,Arthritis, Rheumatoid ,Gait (human) ,Physical medicine and rehabilitation ,Activities of Daily Living ,medicine ,Humans ,Orthopedics and Sports Medicine ,Functional ability ,Circadian rhythm ,Rheumatoid arthritis ,Gait ,Aged ,Aged, 80 and over ,business.industry ,Diurnal temperature variation ,Middle Aged ,medicine.disease ,Circadian Rhythm ,Diurnal variation ,Joint stiffness ,Gait analysis ,Physical therapy ,Female ,medicine.symptom ,business ,human activities - Abstract
Background Circadian variation of joint stiffness (morning stiffness) and its impact on functional ability are widely recognised in rheumatoid arthritis. Subsequent within-day variation of walking ability is important due to the increased availability of instrumented gait analysis. This study aimed to quantify diurnal variation of gait in patients with rheumatoid arthritis, and explore associations with disease characteristics. Methods Thirty one inpatients with rheumatoid arthritis walked at a self-selected speed along a GAITRite instrumented walkway 5 times during a single day. Findings Participants showed marked diurnal variation in gait, leading to a systematic variation throughout the day (F = 19.56, P =, Highlights • Patients with rheumatoid arthritis exhibited a systematic change in walking ability throughout the day. • The magnitude of within day change appeared independent of disease characteristics. • In future, repeat measures should be conducted at the same time of day to exclude the effects of diurnal variation.
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- 2014
17. Basic Science * 208. Stem Cell Factor Expression is Increased in the Skin of Patients with Systemic Sclerosis and Promotes Proliferation and Migration of Fibroblasts in vitro
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S. Karrar, X. Shiwen, J. Nikotorowicz-Buniak, D. J. Abraham, C. Denton, R. Stratton, R. Bayley, K. A. Kite, E. Clay, J. P. Smith, G. D. Kitas, C. Buckley, S. P. Young, L. Ye, L. Zhang, J. Goodall, H. Gaston, H. Xu, P. M. Lutalo, Y. Zhao, L. Meng Choong, S. Sangle, J. Spencer, D. D'Cruz, O. J. Rysnik, K. McHugh, P. Bowness, L. Rump-Goodrich, D. Mattey, O. Kehoe, J. Middleton, A. Cartwright, C. Schmutz, A. Askari, D. H. Gardner, L. E. Jeffery, K. Raza, D. M. Sansom, M. Fitzpatrick, G. Wallace, S. Young, J. Shaw, H. Hatano, A. Cauli, J. L. Giles, A. Mathieu, S. Kollnberger, S. Webster, L. Ellis, L. M. O'Brien, T. J. Fitzmaurice, A. Nazeer Moideen, L. Evans, L. Osgood, A. Williams, S. Jones, C. Thomas, V. O'Donnell, M. Nowell, L. Ouboussad, S. Savic, L. J. Dickie, J. Hintze, C. H. Wong, G. P. Cook, M. Buch, P. Emery, M. F. McDermott, S. A. Hardcastle, C. L. Gregson, K. Deere, G. Davey Smith, P. Dieppe, J. H. Tobias, E. Dennison, M. Edwards, J. Bennett, D. Coggon, K. Palmer, C. Cooper, D. McWilliams, A. Young, P. D. Kiely, D. Walsh, H. J. Taylor, I. Harding, J. Hutchinson, I. Nelson, A. Blom, J. Tobias, E. Clark, J. Parker, M. Bukhari, K. Jayakumar, P. Kiely, J. Diffin, M. Lunt, T. Marshall, J. Chipping, D. Symmons, S. Verstappen, J. Bluett, J. Bowes, P. Ho, N. McHugh, D. Buden, O. Fitzgerald, A. Barton, J. R. Glossop, N. B. Nixon, R. D. Emes, P. T. Dawes, W. E. Farrell, D. L. Mattey, I. C. Scott, S. Steer, S. Seegobin, A. M. Hinks, S. Eyre, A. Morgan, A. G. Wilson, L. Hocking, P. Wordsworth, J. Worthington, A. Cope, C. M. Lewis, S. Guerra, B. A. Ahmed, D. Abraham, C. Fonseca, J. Robinson, J. Taylor, L. Haroon Rashid, E. Flynn, J. Isaacs, J. H. Barrett, B. Kingston, M. Ahmed, J. R. Kirwan, R. Marshall, K. Chapman, R. Pearson, C. Heycock, C. Kelly, M. Rynne, V. Saravanan, J. Hamilton, A. Saeed, R. Coughlan, J. J. Carey, Z. Farah, W. Matthews, C. Bell, S. Petford, L.-M. Tibbetts, K. M. J. Douglas, W. Holden, J. Ledingham, M. Fletcher, R. Winfield, Z. Price, K. Mackay, C. Dixon, R. Oppong, S. Jowett, E. Nicholls, D. Whitehurst, S. Hill, A. Hammond, E. Hay, K. Dziedzic, C. Righetti, M. Lebmeier, V. L. Manning, M. Hurley, D. L. Scott, E. Choy, L. Bearne, E. Nikiphorou, S. Morris, D. James, E. C. Wong, J. Long, A. Fletcher, S. Holmes, P. Hockey, M. Abbas, C. Chattopadhyay, J. Flint, M. Gayed, K. Schreiber, S. Arthanari, M. Nisar, M. Khamashta, C. Gordon, I. Giles, J. Robson, A. Kiran, J. Maskell, N. Arden, A. Hutchings, A. Emin, D. Culliford, B. Dasgupta, W. Hamilton, R. Luqmani, H. Jethwa, D. Rowczenio, H. Trojer, T. Russell, J. Loeffler, P. Hawkins, H. Lachmann, I. Verma, A. Syngle, P. Krishan, N. Garg, S. P. McGowan, D. T. Gerrard, H. Chinoy, W. E. Ollier, R. G. Cooper, J. A. Lamb, L. Taborda, P. Correia Azevedo, D. Isenberg, K. M. Leyland, A. Judge, D. Hunter, D. Hart, M. K. Javaid, M. H. Edwards, A. E. Litwic, K. A. Jameson, D. Deeg, J. Cushnaghan, A. Aihie Sayer, D. Jagannath, C. Parsons, L. Stoppiello, P. Mapp, S. Ashraf, D. Wilson, R. Hill, B. Scammell, C. Wenham, P. Shore, R. Hodgson, A. Grainger, J. Aaron, L. Hordon, P. Conaghan, Y. Bar-Ziv, Y. Beer, Y. Ran, S. Benedict, N. Halperin, M. Drexler, A. Mor, G. Segal, A. Lahad, A. Haim, U. Rath, D. M. Morgensteren, M. Salai, A. Elbaz, V. G. Vasishta, E. Derrett-Smith, R. Hoyles, K. Khan, A. Ezeonyeji, G. Takhar, V. Ong, L. Loughrey, L.-A. Bissell, E. Hensor, G. Abignano, A. Redmond, F. Del Galdo, F. C. Hall, A. Malaviya, S. Baker, A. Furlong, A. Mitchell, A. L. Godfrey, M. Ruddlesden, A. Hadjinicolaou, M. Hughes, T. Moore, N. O'Leary, A. Tracey, H. Ennis, G. Dinsdale, C. Roberts, A. Herrick, C. P. Denton, L. Guillevin, E. Hunsche, D. Rosenberg, B. Schwierin, M. Scott, T. Krieg, M. Anderson, M. Matucci-Cerinic, R. Alade, S. Xu, S. Nihtyanova, K. E. Clark, F. W. K. Tam, R. Unwin, R. J. Stratton, B. Schreiber, C. Seng Edwin Lim, E. Corsiero, N. Sutcliffe, H. Wardemann, C. Pitzalis, M. Bombardieri, H. Tahir, S. Donnelly, M. Greenwood, T. O. Smith, V. Easton, H. Bacon, E. Jerman, K. Armon, F. Poland, A. Macgregor, D. van der Heijde, J. Sieper, D. Elewaut, A. L. Pangan, D. Nguyen, C. Badenhorst, S. Kirby, D. White, A. Harrison, J. A. Garcia, S. Stebbings, J. W. MacKay, S. Aboelmagd, K. Gaffney, A. Deodhar, J. Braun, M. Mack, B. Hsu, T. Gathany, C. Han, R. D. Inman, N. Cooper-Moss, J. Packham, V. Strauss, J. E. Freeston, L. Coates, J. Nam, A. R. Moverley, P. Helliwell, R. Wakefield, P. Mease, R. Fleischmann, J. Wollenhaupt, D. Kielar, F. Woltering, C. Stach, B. Hoepken, T. Arledge, D. Gladman, G. Coteur, A. Kavanaugh, O. Purcaru, I. McInnes, A. B. Gottlieb, L. Puig, P. Rahman, C. Ritchlin, S. Li, Y. Wang, A. Mendelsohn, M. Doyle, W. Tillett, D. Jadon, G. Shaddick, C. Cavill, G. Robinson, R. Sengupta, E. Korendowych, C. de Vries, R. C. Thomas, T. Shuto, N. Busquets-Perez, H. Marzo-Ortega, D. McGonagle, G. Richards, S. Bingham, P. John Hamlin, R. Adshead, S. Cambridge, P. Suppiah, M. Cullinan, A. Nolan, W. M. Thompson, H. R. Mathieson, S. L. Mackie, D. Bryer, M. Krutikov, L. Gray, E. Bruce, A. Keat, W. Innes, R. Pandit, L. Kay, S. Lapshina, L. Myasoutova, S. Erdes, D. Wallis, N. Waldron, I. Thorne, C. Harris, K. Vohra, D. Khinchi, L. Kaur, A. Jones, N. Harrison, D. Harris, T. Jones, J. Rees, A. Bennett, S. Fazal, N. Tugnet, N. Barkham, N. Basu, A. McClean, L. Harper, E. N. Amft, N. Dhaun, R. A. Luqmani, M. A. Little, D. R. Jayne, O. Flossmann, J. McLaren, V. Kumar, D. M. Reid, G. J. Macfarlane, G. Jones, M. Yates, R. A. Watts, L. Igali, C. Mukhtyar, H. Doll, S. Yew, R. Suppiah, P. Hoglund, D. Jayne, K. Westman, W. Win Maw, P. Patil, M. Williams, T. Adizie, D. Christidis, F. Borg, A. Robertson, A. P. Croft, S. Smith, S. Carr, S. Youssouf, A. Salama, C. Pusey, and M. Morgan
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medicine.medical_specialty ,business.industry ,Stem cell factor ,Systemic scleroderma ,medicine.disease ,In vitro ,Rheumatology ,medicine.anatomical_structure ,Internal medicine ,Immunology ,medicine ,Pharmacology (medical) ,Fibroblast ,business - Published
- 2013
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18. E72 Awareness of Inflammatory Back Pain and Axial Spondyloarthopathy in Secondary Care
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Helena Marzo-Ortega, Karl Gaffney, Hannah R. Mathieson, and Mira Merashli
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Secondary care ,medicine.medical_specialty ,Physical medicine and rehabilitation ,Inflammatory back pain ,business.industry ,Physical therapy ,medicine ,Back pain ,medicine.symptom ,business - Published
- 2016
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19. Phenobarbital reduces EEG amplitude and propagation of neonatal seizures but does not alter performance of automated seizure detection
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Sean R, Mathieson, Vicki, Livingstone, Evonne, Low, Ronit, Pressler, Janet M, Rennie, and Geraldine B, Boylan
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Electroclinical uncoupling ,Phenobarbital ,Infant, Newborn ,Humans ,Anticonvulsants ,Electroencephalography ,sense organs ,Neonatal seizures ,skin and connective tissue diseases ,Epilepsy, Benign Neonatal ,Article ,Automated seizure detection - Abstract
Highlights • Phenobarbital reduces both amplitude and propagation of neonatal seizures. • These changes may help to explain electroclinical uncoupling. • The performance of our seizure detection algorithm was unaffected., Objective Phenobarbital increases electroclinical uncoupling and our preliminary observations suggest it may also affect electrographic seizure morphology. This may alter the performance of a novel seizure detection algorithm (SDA) developed by our group. The objectives of this study were to compare the morphology of seizures before and after phenobarbital administration in neonates and to determine the effect of any changes on automated seizure detection rates. Methods The EEGs of 18 term neonates with seizures both pre- and post-phenobarbital (524 seizures) administration were studied. Ten features of seizures were manually quantified and summary measures for each neonate were statistically compared between pre- and post-phenobarbital seizures. SDA seizure detection rates were also compared. Results Post-phenobarbital seizures showed significantly lower amplitude (p
- Published
- 2016
20. Kv3.1b and Kv3.3 channel subunit expression in murine spinal dorsal horn GABAergic interneurones
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A.E. King, R.J. Chapman, A. Nowak, Hannah R. Mathieson, K. Obata, Yuchio Yanagawa, Gergely Janzsó, and Gábor Szabó
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c-fos ,Nociception ,endocrine system diseases ,Protein subunit ,Glutamate decarboxylase ,Population ,Pain ,Mice, Transgenic ,Biology ,Article ,gamma-Aminobutyric acid ,Mice ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Interneurons ,medicine ,Noxious stimulus ,Animals ,Gene Knock-In Techniques ,Potassium channel ,Posterior Horn Cell ,education ,gamma-Aminobutyric Acid ,030304 developmental biology ,0303 health sciences ,education.field_of_study ,Glutamate Decarboxylase ,fungi ,Immunohistochemistry ,Cell biology ,Mice, Inbred C57BL ,Posterior Horn Cells ,Shaw Potassium Channels ,nervous system ,GAD65 ,GAD67 ,Excitatory postsynaptic potential ,GABAergic ,Capsaicin ,Neuroscience ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Highlights ► Kv3.1b and Kv3.3 expression was studied in dorsal horn GABAergic interneurones. ► Kv3.1b or Kv3.3 was most abundantly expressed in laminae I–III. ► Kv3.1b but not Kv3.3 was associated with GAD65 and GAD67 neurones. ► Capsaicin-induced c-fos expression was localized mainly to GAD65-GFP interneurones., GABAergic interneurones, including those within spinal dorsal horn, contain one of the two isoforms of the synthesizing enzyme glutamate decarboxylase (GAD), either GAD65 or GAD67. The physiological significance of these two GABAergic phenotypes is unknown but a more detailed anatomical and functional characterization may help resolve this issue. In this study, two transgenic Green Fluorescent Protein (GFP) knock-in murine lines, namely GAD65-GFP and GAD67-GFP (Δneo) mice, were used to profile expression of Shaw-related Kv3.1b and Kv3.3 K+-channel subunits in dorsal horn interneurones. Neuronal expression of these subunits confers specific biophysical characteristic referred to as ‘fast-spiking’. Immuno-labelling for Kv3.1b or Kv3.3 revealed the presence of both of these subunits across the dorsal horn, most abundantly in laminae I–III. Co-localization studies in transgenic mice indicated that Kv3.1b but not Kv3.3 was associated with GAD65-GFP and GAD67-GFP immunopositive neurones. For comparison the distributions of Kv4.2 and Kv4.3 K+-channel subunits which are linked to an excitatory neuronal phenotype were characterized. No co-localization was found between GAD-GFP +ve neurones and Kv4.2 or Kv4.3. In functional studies to evaluate whether either GABAergic population is activated by noxious stimulation, hindpaw intradermal injection of capsaicin followed by c-fos quantification in dorsal horn revealed co-expression c-fos and GAD65-GFP (quantified as 20–30% of GFP +ve population). Co-expression was also detected for GAD67-GFP +ve neurones and capsaicin-induced c-fos but at a much reduced level of 4–5%. These data suggest that whilst both GAD65-GFP and GAD67-GFP +ve neurones express Kv3.1b and therefore may share certain biophysical traits, their responses to peripheral noxious stimulation are distinct.
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- 2011
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21. Poor awareness of inflammatory back pain and axial spondyloarthritis among secondary care specialists
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Mira Merashli, Helena Marzo-Ortega, Hannah R. Mathieson, and Karl Gaffney
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030203 arthritis & rheumatology ,medicine.medical_specialty ,Delayed Diagnosis ,business.industry ,Inflammatory back pain ,Alternative medicine ,MEDLINE ,General Medicine ,Delayed diagnosis ,Secondary Care ,Rheumatology ,Secondary care ,03 medical and health sciences ,0302 clinical medicine ,Back Pain ,Health Care Surveys ,Internal medicine ,Spondylarthritis ,medicine ,Physical therapy ,Humans ,030212 general & internal medicine ,Axial spondyloarthritis ,business - Published
- 2016
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22. 1 Imaging and intervention in abdominal emergencies
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John R. Mathieson and Raymond F. McLoughlin
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medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Radiography ,Radiological weapon ,Intervention (counseling) ,Gastroenterology ,medicine ,Computed tomography ,Magnetic resonance imaging ,Radiology ,Medical diagnosis ,business - Abstract
While plain abdominal radiographs retain an essential place in acute abdominal emergencies, the dramatic advances in ultrasound, computed tomography and magnetic resonance imaging witnessed over the past two decades have revolutionized the practice of emergency medicine. Crosssectional imaging techniques now play a key role in evaluating patients with abdominal emergencies, and allow confident diagnoses to be made in an ever increasing proportion of these patients. Unnecessary laparotomies are now uncommon, and a wide array of interventional radiological techniques can be used to treat abdominal emergencies without surgery.
- Published
- 1995
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23. Abdominal abnormalities in AIDS: detection at US in a large population
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P L Cooperberg, J R Mathieson, and F J Smith
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Male ,medicine.medical_specialty ,Pathology ,Biliary Tract Diseases ,Hepatosplenomegaly ,Gastroenterology ,Internal medicine ,Abdomen ,Ascites ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Lymphatic Diseases ,Ultrasonography ,Acquired Immunodeficiency Syndrome ,medicine.diagnostic_test ,business.industry ,Bile duct ,Liver Diseases ,Gallbladder ,medicine.anatomical_structure ,Abdominal ultrasonography ,Splenomegaly ,Abnormal Liver Function Test ,Female ,medicine.symptom ,Abnormality ,business ,Complication - Abstract
The authors studied the prevalence of abnormalities at abdominal ultrasonography (US) in patients with acquired immunodeficiency syndrome (AIDS), the temporal change in prevalence, and the use of US to correlate clinical indications with these abnormalities.From 1983 to 1991, 899 AIDS patients were seen, representing 89.36% of the 1,006 AIDS patients in the province during that time. Of these, 414 underwent 684 US studies, 399 of which were able to be reviewed.US results showed abnormalities in 264 of the 399 studies, including splenomegaly (n = 124), lymphadenopathy (n = 83]), gallbladder and bile duct abnormalities (n = 80), hepatomegaly (n = 77), and ascites (n = 54). Clinical indications with the highest frequency of abnormal findings included hepatosplenomegaly (n = 337) and abnormal liver function tests (n = 270). Lymph nodes more than 3 cm in diameter (in 10 of 83 patients with enlarged nodes) always represented an abnormality other than reactive hyperplasia. The percentage of abnormal results went from 25% in 1984 (two of nine studies) to 81% in 1990 (77 of 95 studies).The prevalence of abdominal abnormalities depicted at US in AIDS patients has increased since 1983.
- Published
- 1994
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24. Malignant obstruction of the common bile duct: long-term results of Gianturco-Rosch metal stents used as initial treatment
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N Schmidt, S N Stordy, P L Cooperberg, J R Mathieson, R F McLoughlin, J. K. MacFarlane, and C C Prystai
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Adult ,Male ,medicine.medical_specialty ,Palliative care ,Common Bile Duct Diseases ,medicine.medical_treatment ,Cholangiocarcinoma ,Cholangiography ,Cholestasis ,medicine ,Humans ,Initial treatment ,Radiology, Nuclear Medicine and imaging ,Prospective Studies ,Prospective cohort study ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,Common bile duct ,business.industry ,Palliative Care ,Stent ,Long term results ,Cholestasis, Extrahepatic ,Middle Aged ,medicine.disease ,Surgery ,Pancreatic Neoplasms ,medicine.anatomical_structure ,Bile Duct Neoplasms ,Metals ,Female ,Stents ,business - Abstract
To determine how long Gianturco-Rosch metal stents remain patent when used as the initial treatment for malignant obstruction of the common bile duct.The patency of Gianturco-Rosch metal stents was prospectively studied in 26 patients with malignant obstructive jaundice. Biliary obstruction was caused by pancreatic carcinoma (n = 15), cholangiocarcinoma (n = 10), or metastatic lymphadenopathy (n = 1). Follow-up information was obtained every 3-4 months until death.Stent insertion was successful in all patients. Stent occlusion occurred in nine patients (35%). The overall mean patency period was 39.9 weeks. Adequate biliary drainage for a minimum of 80 weeks or until death was achieved in 19 patients (73%). Life-table analysis predicted stent patency rates of 86%, 75%, and 69% at 12, 24, and 48 weeks, respectively.These results are better than those previously reported in patients with plastic endoprostheses. The authors believe that insertion of the metal stent is the procedure of choice in patients with inoperable malignant biliary obstruction.
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- 1994
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25. FPs and Hospitals
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R, Mathieson
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Letters - Published
- 2011
26. Comparison of a chemical and a biological method for the assay of a purified digitalis preparation
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H J, DANOW, D R, MATHIESON, and H W, HAYS
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Digitalis ,Plant Extracts ,Digitalis Glycosides ,Biological Assay ,Reference Standards - Published
- 2010
27. Factors affecting the hatching of ova of Schistosoma japonicum
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T B, MAGATH and D R, MATHIESON
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Eggs ,Animals ,Humans ,Schistosoma ,Schistosoma japonicum ,Ovum - Published
- 2010
28. Important factors in the epidemiology of schistosomiasis in Leyte
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T B, MAGATH and D R, MATHIESON
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Biometry ,Schistosomiasis - Published
- 2010
29. The present status of tropical and exotic diseases among servicemen
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D R, MATHIESON
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Tropical Medicine ,Humans ,Military Medicine ,Veterans - Published
- 2010
30. Mobility in musculokeletal disease: compromise and compensations: IP76. Why do People with Neurogenic Claudication Like Shopping?
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C. Comer, D. White, P. Conaghan, A. C. Redmond, S. Muller, E. Thomas, G. Peat, M. R. Backhouse, D. A. Pickles, H. R. Mathieson, L. Edgson, P. Emery, H. Bird, P. Helliwell, M. van der Leeden, R. Dahmen, J. Ursum, L. D. Roorda, D. van Schaardenburg, D. L. Knol, M. P. Steultjens, and J. Dekker
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medicine.medical_specialty ,business.industry ,Pseudoclaudication syndrome ,Compromise ,media_common.quotation_subject ,Lumbar spinal stenosis ,Neurogenic claudication ,Disease ,medicine.disease ,Physical medicine and rehabilitation ,Rheumatology ,medicine ,Physical therapy ,Pharmacology (medical) ,medicine.symptom ,business ,media_common - Published
- 2011
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31. HIV Transmission Prevention for Health Care Workers
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Eric van Sonnenberg, John R. Mathieson, and Jacques W. A. J. Reeders
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medicine.medical_specialty ,business.industry ,Human immunodeficiency virus (HIV) ,medicine.disease ,medicine.disease_cause ,Medical care ,Acquired immunodeficiency syndrome (AIDS) ,Universal precautions ,Family medicine ,Health care ,medicine ,Percutaneous cholecystostomy ,Hiv transmission ,business ,Disease transmission - Abstract
The impact of AIDS has included a fundamental reappraisal of methods of disease transmission, and the type of risks posed not only to health care professionals, but also to the public seeking medical care.
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- 2001
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32. Spontaneous portal-right renal vein shunt in portal hypertension
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P L Cooperberg, R F McLoughlin, J R Mathieson, and S M Dashefsky
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Male ,medicine.medical_specialty ,Portal venous pressure ,Collateral Circulation ,Contrast Media ,Inferior vena cava ,Renal Veins ,Hypertension, Portal ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Ultrasonography, Doppler, Color ,Radiological and Ultrasound Technology ,business.industry ,Vascular disease ,Portal Vein ,Middle Aged ,Collateral circulation ,medicine.disease ,Shunt (medical) ,Surgery ,medicine.vein ,Portal hypertension ,Renal vein ,Complication ,business ,Tomography, X-Ray Computed - Published
- 1995
33. High resolution endoluminal ultrasonography in the staging of esophageal carcinoma
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P L Cooperberg, L S Halparin, J R Mathieson, S N Stordy, and R F McLoughlin
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Adult ,Male ,medicine.medical_specialty ,Esophageal Neoplasms ,High resolution ,Adenocarcinoma ,medicine ,Carcinoma ,Humans ,Radiology, Nuclear Medicine and imaging ,Esophagus ,Stage (cooking) ,Lymph node ,Aged ,Neoplasm Staging ,Ultrasonography ,Aged, 80 and over ,Radiological and Ultrasound Technology ,Epithelioma ,Esophageal disease ,business.industry ,Middle Aged ,medicine.disease ,medicine.anatomical_structure ,Carcinoma, Squamous Cell ,Feasibility Studies ,Female ,Radiology ,business - Abstract
Small catheters containing 20 MHz transducers have recently become available for high resolution endoluminal ultrasound. We report our early use of this technique to image and stage esophageal carcinoma. Fifteen patients undergoing high resolution endoluminal ultrasonography for suspected esophageal carcinoma were studied. Twelve of these patients also underwent computed tomography and pathologic correlation was available in seven. Satisfactory esophageal examination was possible in 14 of 15 patients. Of those with pathologic correlation, the depth of tumor invasion was correctly staged by high resolution endoluminal ultrasonography in six of seven patients and by computed tomography in only three of seven patients. Lymph node assessment correlated poorly with pathologic findings for both high resolution endoluminal ultrasound and computed tomography. With the increasing use of preoperative radiation therapy, we believe these early results predict a potential role for high resolution endoluminal ultrasonography in the staging of esophageal carcinoma.
- Published
- 1995
34. Sonographic assessment of infrarenal inferior vena caval dimensions
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Anne Marie G. Sykes, P L Cooperberg, J R Mathieson, R F McLoughlin, R. Brandt, C.-B. B. So, and R. R. Gray
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Inferior vena caval ,Adult ,Male ,medicine.medical_specialty ,Quiet respiration ,Valsalva Maneuver ,Movement ,Vena Cava, Inferior ,Inferior vena cava ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Aged ,Ultrasonography ,Aged, 80 and over ,Leg ,Radiological and Ultrasound Technology ,business.industry ,Respiration ,Middle Aged ,body regions ,medicine.vein ,cardiovascular system ,Feasibility Studies ,Regression Analysis ,Female ,Radiology ,business - Abstract
The dimensions of the infrarenal inferior vena cava during quiet respiration, single leg lifting, and breath-holding were assessed using sonography in 156 patients. Sonographic assessment of infrarenal inferior vena caval dimensions was feasible in 69% of patients. Measurements during breath-holding were significantly greater than during quiet respiration (P < 0.001) and leg lifting (P < 0.005), although in approximately one quarter of the patients the mean calculated diameter was greatest during quiet respiration. we conclude that sonographic assessment of infrarenal inferior vena caval dimensions is feasible, but it should be performed during quiet respiration and breath-holding to allow for variation with different respiratory maneuvers.
- Published
- 1995
35. Peritoneal abscesses due to bowel perforation: effect of extent on outcome after percutaneous drainage
- Author
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John R. Mathieson, Peter L. Cooperberg, Raymond F. McLoughlin, Kenneth G. Atkinson, Ralph M. Christensen, and John K. MacFarlane
- Subjects
Adult ,Male ,medicine.medical_specialty ,Percutaneous ,Colon ,Bowel perforation ,Peritoneal Diseases ,Catheterization ,Patient age ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,In patient ,Drainage ,Aged ,Retrospective Studies ,Aged, 80 and over ,Immune status ,business.industry ,Anastomosis, Surgical ,Age Factors ,Middle Aged ,Appendicitis ,Abscess ,Surgery ,Treatment Outcome ,Intestinal Perforation ,Linear Models ,Female ,Radiology ,Peritoneum ,Cardiology and Cardiovascular Medicine ,business - Abstract
Purpose To determine the effect of extent of peritoneal contamination in enteric abscesses on final outcome and duration of percutaneous drainage. Patients and Methods Results were retrospectively reviewed for 11 patients with varying degrees of peritoneal contamination secondary to subacute bowel perforation who were primarily treated with percutaneous drainage. Stepwise linear regression analysis of duration of drainage was performed with use of patient age and immune status, the site of bowel perforation, and the number of peritoneal compartments involved in the resultant contamination as independent variables. Results In 10 of 11 patients (91%) treatment of the resultant intraperitoneal collections with percutaneous drainage was successful irrespective of the extent of peritoneal contamination. There was no correlation between duration of drainage and extext of peritoneal contamination but good correlation with patient age and site of bowel perforation ( r =0.82, P =.02). Conclusion In patients with enteric abscesses due to subacute bowel perforation, the duration of drainage and final outcome after percutaneous drainage are independent of the extent of peritoneal contamination.
- Published
- 1995
36. Imaging and intervention in abdominal emergencies
- Author
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R F, McLoughlin and J R, Mathieson
- Subjects
Abdomen, Acute ,Diagnostic Imaging ,Gastrointestinal Diseases ,Digestive System Diseases ,Humans ,Abdominal Injuries ,Emergencies ,Radiology, Interventional - Abstract
While plain abdominal radiographs retain an essential place in acute abdominal emergencies, the dramatic advances in ultrasound, computed tomography and magnetic resonance imaging witnessed over the past two decades have revolutionized the practice of emergency medicine. Cross-sectional imaging techniques now play a key role in evaluating patients with abdominal emergencies, and allow confident diagnoses to be made in an ever increasing proportion of these patients. Unnecessary laparotomies are now uncommon, and a wide array of interventional radiological techniques can be used to treat abdominal emergencies without surgery.
- Published
- 1995
37. Radiologically guided percutaneous cholecystostomy for acute cholecystitis: long-term outcome in 50 patients
- Author
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R F, McLoughlin, E J, Patterson, J R, Mathieson, P L, Cooperberg, and J K, MacFarlane
- Subjects
Adult ,Aged, 80 and over ,Male ,Time Factors ,Middle Aged ,Prognosis ,Radiography ,Treatment Outcome ,Cholelithiasis ,Acute Disease ,Cholecystitis ,Humans ,Female ,Cholecystostomy ,Aged ,Follow-Up Studies - Abstract
To assess the long-term outcome in patients with acute cholecystitis treated initially by percutaneous cholecystostomy, the authors reviewed the medical and radiology records of all such patients treated at their hospital from January 1990 to September 1993. Of the 50 patients, 29 had calculous and 21 had acalculous cholecystitis. In the group with calculous cholecystitis, 1 of the patients required no further treatment, 3 subsequently underwent percutaneous stone removal, 14 underwent elective cholecystectomy, 6 underwent emergency cholecystectomy and 5 died of the underlying condition shortly after cholecystostomy. In the group with acalculous cholecystitis, 12 of the patients needed no further treatment after a mean follow-up period of 12 months; 8 of these underwent follow-up ultrasound examination, which revealed gallbladder calculi in only 1 patient. Four patients underwent elective cholecystectomy, 1 underwent emergency cholecystectomy, and 4 died of the underlying condition shortly after cholecystostomy. Over the long term, 23 (79%) of the 29 patients with calculous cholecystitis underwent surgery or removal of calculi. In the other group surgery was required in only 5 (24%) of the 21 patients. The authors conclude that percutaneous cholecystostomy is a useful temporizing measure, which allows patients with calculous cholecystitis to undergo elective cholecystectomy. In most cases of acalculous cholecystitis the procedure is curative, obviating the need for cholecystectomy.
- Published
- 1994
38. Effect of hyoscine butylbromide on gastroesophageal reflux in barium studies of the upper gastrointestinal tract
- Author
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R F, McLoughlin, J R, Mathieson, P M, Chipperfield, M R, Grymaloski, and A D, Wong
- Subjects
Radiography ,Butylscopolammonium Bromide ,Gastroesophageal Reflux ,Humans ,Barium Sulfate ,Digestive System - Abstract
Hyoscine butylbromide (Buscopan) is an intravenously administered hypotonic agent that significantly reduces pressure in the lower esophageal sphincter and may therefore artificially induce gastroesophageal reflux during barium examination of the upper gastrointestinal tract. This study was performed to test this hypothesis. The presence or absence and severity of gastroesophageal reflux before and after intravenous injection of 20 mg Buscopan were evaluated in 112 consecutive patients undergoing biphasic upper gastrointestinal examination. Gastroesophageal reflux was seen in 49 (44%) of the patients. Reflux was evident both before and after the injection of Buscopan in 35 (31%) of the patients, before injection only in 10 (9%) and after injection only in 4 (4%). The magnitude of reflux after injection of Buscopan was reduced or the same in 108 of the patients (96%) and increased in 4 (4%). There was no significant difference in the overall occurrence (p = 0.41) or degree (p = 0.81) of gastroesophageal reflux before and after injection of Buscopan (chi 2 test). The authors conclude that the routine use of Buscopan is unlikely to spuriously increase the frequency or degree of gastroesophageal reflux observed on upper gastrointestinal barium studies.
- Published
- 1994
39. Systematic transrectal ultrasound-guided biopsy of the prostate
- Author
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S J, Garber, S L, Goldenberg, P L, Cooperberg, A D, Wong, J H, Bilby, and J R, Mathieson
- Subjects
Male ,Biopsy, Needle ,Prostate ,Humans ,Prostatic Neoplasms ,Prospective Studies ,Adenocarcinoma ,Sensitivity and Specificity ,Ultrasonography, Interventional - Abstract
This study was undertaken to confirm the utility of systematic transrectal ultrasound-guided prostate biopsy in diagnosing cancer in patients with abnormal findings on digital rectal examination or abnormal levels of prostate-specific antigen (or both). The authors also wanted to determine the diagnostic advantage of taking six sextant biopsy samples rather than four quadrant samples. In a prospective study of 669 men examined between July 1992 and April 1993 at a tertiary-care hospital, core samples were obtained from any visualized or palpated abnormalities, the three other "normal" quadrants (apices and bases) and the two parasagittal midzones. The glands of 403 of the patients (60%) had an abnormality detectable by ultrasonography, and 233 of the patients (35%) had adenocarcinoma, proven by histologic examination. Of the 169 cases of adenocarcinoma initially indicated by ultrasonography, the suspected lesion was histologically benign in 66 (39%), but malignancy was found in another portion of the gland. In 18 (8%) of the 233 patients with adenocarcinoma, the only positive result was obtained from the additional core biopsy samples from the midzone. This study confirms that the ultrasonographic characteristics of cancer are variable, that many tumours (130 [56%] in this study) are detected in areas that are normal on ultrasonography and digital rectal examination, and that the detection sensitivity is increased (by 8% in this study) when two midlobe parasagittal plane biopsy samples are added to the four standard quadrant samples.
- Published
- 1994
40. Percutaneous reconstruction of the common hepatic duct with a metal stent after accidental surgical resection
- Author
-
Ralph M. Christensen, John K. MacFarlane, Robert M. Baird, Ray F. McLoughlin, John R. Mathieson, and Peter L. Cooperberg
- Subjects
Surgical resection ,Adult ,medicine.medical_specialty ,Percutaneous ,business.industry ,medicine.medical_treatment ,Stent ,Hepatic Duct, Common ,Radiography ,medicine.anatomical_structure ,Catheters, Indwelling ,Common hepatic duct ,Cholecystectomy, Laparoscopic ,Accidental ,Medicine ,Drainage ,Humans ,Radiology, Nuclear Medicine and imaging ,Female ,Stents ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Intraoperative Complications ,Laparoscopic cholecystectomy - Published
- 1994
41. Percutaneous cholecystostomy: safety of the transperitoneal route
- Author
-
Steven J. Garber, John K. MacFarlane, John R. Mathieson, and Peter L. Cooperberg
- Subjects
Male ,medicine.medical_specialty ,Catheterization ,Hematoma ,Postoperative Complications ,Catheter drainage ,medicine ,Acute cholecystitis ,Cholecystitis ,Percutaneous cholecystostomy ,Humans ,Radiology, Nuclear Medicine and imaging ,In patient ,Cholecystostomy ,Bile leak ,Retrospective Studies ,business.industry ,Gallbladder ,Retrospective cohort study ,Middle Aged ,medicine.disease ,medicine.anatomical_structure ,Acute Disease ,Drainage ,Female ,Radiology ,Cardiology and Cardiovascular Medicine ,business - Abstract
Purpose The authors analyzed the safety and efficacy of trans-peritoneal percutaneous cholecystostomy (PC) in patients with acute cholecystitis. Patients and Methods Thirty-four consecutive patients underwent transperitoneal PC for treatment of acute cholecystitis. A trocar technique was used for placement of the drainage catheter. Results PC was technically successful in all patients. In 27 (79%) of 34 patients, symptoms of acute cholecystitis resolved within 7 days. Minor complications occurred in two patients (5%). Both patients developed a hematoma adjacent to the gallbladder; these resolved without treatment. No cases of bile leak or bile peritonitis occurred. Conclusion The transperitoneal route is safe and effective for PC.
- Published
- 1994
42. Quality of mucosal coating in double-contrast barium enema studies: comparison of two barium preparations
- Author
-
H J, Bray and J R, Mathieson
- Subjects
Radiography ,Colon ,Viscosity ,Humans ,Enema ,Barium Sulfate ,Retrospective Studies - Abstract
To determine which of two types of barium preparation, a dry powder (AC-14, E-Z-EM, Montreal) or a premixed suspension (Liquid Polibar Plus, E-Z-EM), gives better mucosal coating for double-contrast enema studies, the authors compared the results of two series of 80 examinations each, one for each of the preparations. The films were retrospectively reviewed by two independent observers, who did not know which preparation had been used for a given examination. Mucosal coating was graded on a five-point scale and the amount of barium on a three-point scale. Each area of the colon--the cecum, the ascending, the transverse and the descending colon and the rectosigmoid--was rated separately. The premixed barium suspension yielded significantly better mucosal coating than the dry powder in all areas of the colon (p0.01). There was no significant difference between the two preparations in the amount of barium deposited in any region of the colon (p0.05) or in the proportion of unsatisfactory examinations (p0.05). The authors conclude that the premixed suspension yielded better-quality mucosal coating than a suspension made from the dry powder and resulted in a similar high proportion of technically satisfactory studies.
- Published
- 1993
43. Gait velocity exhibits more than 50% diurnal variation in Rheumatoid Arthritis: the divign study
- Author
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Anthony C. Redmond, Howard A. Bird, Lucy Edgson, Hannah R. Mathieson, Michael R. Backhouse, David Pickles, Paul Emery, and Philip S. Helliwell
- Subjects
medicine.medical_specialty ,lcsh:Diseases of the musculoskeletal system ,business.industry ,Diurnal temperature variation ,Outcome measures ,medicine.disease ,Lower limb ,medicine.anatomical_structure ,Gait velocity ,Physical medicine and rehabilitation ,Gait (human) ,Rheumatoid arthritis ,Poster Presentation ,medicine ,Physical therapy ,Upper limb ,Orthopedics and Sports Medicine ,Circadian rhythm ,lcsh:RC925-935 ,business - Abstract
Gait velocity (GV) is a frequently used outcome measure in studies of the lower limb in RA as it is reliable & correlates with disease impact. Despite recent knowledge of marked circadian variation in inflammatory cytokine levels & upper limb function, little is known about within-day variation of gait in RA.
- Published
- 2010
44. Pancreatic duct obstruction treated with percutaneous antegrade insertion of a metal stent: report of two cases
- Author
-
J R Mathieson, R Christensen, N Schmidt, P L Cooperberg, D J Murray, and S M Dashefsky
- Subjects
Male ,medicine.medical_specialty ,Percutaneous ,Pancreatic disease ,medicine.medical_treatment ,Common Bile Duct Diseases ,Constriction, Pathologic ,Prosthesis ,Asymptomatic ,Catheterization ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Aged ,Pancreatic duct ,Aged, 80 and over ,business.industry ,Pancreatic Ducts ,Stent ,Pancreatic Diseases ,Cholestasis, Extrahepatic ,Middle Aged ,equipment and supplies ,medicine.disease ,Pancreatic duct obstruction ,Surgery ,surgical procedures, operative ,medicine.anatomical_structure ,Pancreatitis ,Metals ,Chronic Disease ,Drainage ,Female ,Stents ,Radiology ,medicine.symptom ,business ,Dilatation, Pathologic - Abstract
Expanding metal stents were used to treat symptomatic pancreatic duct obstruction in two patients with chronic pancreatitis. Both patients initially underwent percutaneous external pancreatic duct drainage and then had metal stents inserted for internal drainage. Both patients remained asymptomatic, and the stents were patent during short-term follow-up periods of 6 and 9 months, respectively. Percutaneous insertion of metal stents, which can be performed to treat pancreatic duct obstruction after a trial of external drainage has been shown to relieve the patient's symptoms, should be considered as an alternative to endoscopic stent placement or surgical drainage.
- Published
- 1992
45. An unusual sonographic appearance: the pyramidal gallstone
- Author
-
J R Mathieson, D T Wall, and P L Cooperberg
- Subjects
medicine.medical_specialty ,Radiological and Ultrasound Technology ,business.industry ,Gallbladder ,Surgery ,Cholecystography ,Cholelithiasis ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Radiology ,business ,Tomography, X-Ray Computed ,Aged ,Ultrasonography - Published
- 1992
46. Testicular microlithiasis: sonographic and clinical features
- Author
-
D L Janzen, P L Cooperberg, P M Del Rio, M D Rifkin, J I Marsh, J R Mathieson, and R H Golding
- Subjects
Adult ,Male ,endocrine system ,medicine.medical_specialty ,Pathology ,endocrine system diseases ,Both testes ,Varicocele ,Testicle ,urologic and male genital diseases ,Asymptomatic ,Testicular Diseases ,Calculi ,Testis ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Retrospective Studies ,Ultrasonography ,urogenital system ,business.industry ,General Medicine ,medicine.disease ,medicine.anatomical_structure ,Abdomen ,Radiology ,Epididymitis ,medicine.symptom ,business ,Testicular microlithiasis ,Scrotal Pain - Abstract
Eleven cases of bilateral diffuse microlithiasis of the testes were evaluated sonographically. The presence of testicular microlithiasis was coincidental to the presence of testicular neoplasms (n = 2), nontesticular malignant lesion in the abdomen or chest (n = 2), subfertility (n = 2), varicocele (n = 1), epididymitis (n = 1), testicular maldescent (n = 1), scrotal trauma (n = 1), and transient scrotal pain (n = 1). Clinical follow-up suggested that testicular microlithiasis is an asymptomatic nonprogressive condition. Sonographic examination of testicular microlithiasis shows diffuse hyperechoic nonshadowing foci measuring 1-2 mm in diameter throughout both testes. The diagnosis of testicular microlithiasis was pathologically proved in five cases. In six cases, the diagnosis was made on the basis of the sonographic appearance (n = 6), clinical information and follow-up (n = 6), and radiologic demonstration of testicular microcalcifications (n = 3). The sonographic appearance of testicular microlithiasis is specific, and we believe that biopsy or orchiectomy in these cases is unnecessary.
- Published
- 1992
47. Empirical Dimensions of Discrimination against Disabled People
- Author
-
AH Neufeldt and R Mathieson
- Subjects
Health (social science) ,Sociology and Political Science ,Human rights ,Societal attitudes ,media_common.quotation_subject ,Disabled people ,Social constructionism ,Dignity ,Perception ,Political Science and International Relations ,Empirical evidence ,Psychology ,Social psychology ,Disadvantage ,media_common - Abstract
Where at one time professionals viewed disability as a condition inherent in a person, there now is widespread acceptance that, in large measure, disability is a social construct with roots in societal attitudes. Specifically, the case has been made by disabled people that they are the victims of discrimination. This paper reviews some of the empirical evidence of discriminatory practices in the areas of: access to education; meaningful participation in the labor force; and, physical and sexual assault. There is ample evidence of discriminatory practices in education and employment which further disadvantage disabled people. Disabled people receive less education and are much less likely to find a job than are non-disabled people and are much more vulnerable than the non-disabled to sexual or physical assault. Promoting and protecting the rights and dignity of disabled people will require a combination of legal approaches, attention to the concrete realities of disability and societal barriers, and changes in the perception of and societal attitudes towards disabled people.
- Published
- 1995
- Full Text
- View/download PDF
48. Acid–base and dyeing properties of Nigerian Merino, Yankasa, and Merino–Yankasa crossbred wools
- Author
-
A. R. Mathieson and M. S. Kazmi
- Subjects
chemistry.chemical_classification ,genetic structures ,Polymers and Plastics ,Titration curve ,Base (chemistry) ,Chemistry ,chemical and pharmacologic phenomena ,General Chemistry ,Crossbreed ,eye diseases ,Surfaces, Coatings and Films ,Amino acid analysis ,Animal science ,Wool ,Materials Chemistry ,Dyeing - Abstract
The acid–base titration curves of three wools, Merino, Yankasa, and a ⅝–⅜ Merino–Yankasa crossbred wool, grown in Nigeria, were measured at 25°C in the presence of varying amounts of sodium chloride. Amino acid analysis was carried out on these wools and correlated with the acid–base properties. The isoionic point and titration curves of Merino and the crossbred wool are similar, while those of Yanakasa are somewhat different. The acid–base behavior was interpreted by the Gibbs–Donnan treatment for the acid titrations and the pK01 values for the carboxyl groups obtained, showing the existence of normal and salt-linked carboxyl groups in these wools. Dyeing tests with acidic and basic dyes have shown that the crossbred wool responds almost as well as Merino. Together with the similarity of its mechanical properties, it seems that this crossbred wool is suitable for all the textile applications for which Merino wool is normally preferred.
- Published
- 1982
- Full Text
- View/download PDF
49. HOME ECONOMICS?THE FUTURE
- Author
-
A. R. Mathieson
- Subjects
business.industry ,Family and consumer science ,Subject (philosophy) ,Medicine ,General Medicine ,Social science ,business ,Educational systems ,Subject matter - Abstract
The future development of the subject matter of home economics, and of the professional activities of home economists, are considered in relation to current developments in the educational system, to discernible trends in lifestyles and to long-term changes in the structure of society. The effects on the subject of the move of the home economics colleges into the universities and polytechnics, the nature of the careers followed by home economists, and of international contacts are also examined.
- Published
- 1979
- Full Text
- View/download PDF
50. Acid–base properties of fibers. Part I. Nylon
- Author
-
C. S. Whewell, A. R. Mathieson, and P. E. Williams
- Subjects
chemistry.chemical_classification ,Nylon 66 ,Materials science ,Polymers and Plastics ,Titration curve ,technology, industry, and agriculture ,hemic and immune systems ,chemical and pharmacologic phenomena ,Hydrochloric acid ,Acid–base titration ,macromolecular substances ,General Chemistry ,Polymer ,Surfaces, Coatings and Films ,chemistry.chemical_compound ,Hydrolysis ,Nylon 6 ,chemistry ,Polymer chemistry ,Materials Chemistry ,Titration - Abstract
The acid-base titration curves of solid nylon 6 resins and nylon 66 fibers have been measured, and isoionic points and endgroups determined. Five nylon 6 polymers of different molecular weights and two commercial nylon 66 yarns have been studied. Titration curves of these materials with hydrochloric acid and sodium hydroxide in the absence of added salt, and of nylon 66 in the presence of added salt, at three different temperatures, and with benzenesulfonic, trichloroacetic, and naphthalene-2-sulfonic acid, allowed the effect of polymer molecular weight, salt, temperature, and anion affinity on the titration curves to be determined. All the results are consistent with the view that nylon possesses a zwitterion structure at neutral pH, carboxyl groups being protonated on acid titration. A proportion of the endgroups is not available to titration in the solid polymers. Existing theories of the acid–base combination of solid polymers fail to explain all the results. The titration curves and elastic properties of the following modified nylon 66 yarns have also been determined and interpreted: nylon deaminated by nitrous acid, dinitrophenylated, acetylated, carboxymethylated, hydrolyzed, and dihydrophenylated nylons, and nylon treated with alkaline hypochlorite, boiling water, and boiling benzene. In all cases the increase in the work to stretch the filament is independent of pH.
- Published
- 1964
- Full Text
- View/download PDF
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