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1.
Eur Radiol ; 26(12): 4413-4422, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27012555

ABSTRACT

OBJECTIVE: To investigate different brain regions for grey (GM) and white matter (WM) damage in a well-defined cohort of neuromyelitis optica spectrum disorder (NMOSD) patients and compare advanced MRI techniques (VBM, Subcortical and cortical analyses (Freesurfer), and DTI) for their ability to detect damage in NMOSD. METHODS: We analyzed 21 NMOSD patients and 21 age and gender matched control subjects. VBM (GW/WM) and DTI whole brain (TBSS) analyses were performed at different statistical thresholds to reflect different statistical approaches in previous studies. In an automated atlas-based approach, Freesurfer and DTI results were compared between NMOSD and controls. RESULTS: DTI TBSS and DTI atlas based analysis demonstrated microstructural impairment only within the optic radiation or in regions associated with the optic radiation (posterior thalamic radiation p < 0.001, 6.9 % reduction of fractional anisotropy). VBM demonstrated widespread brain GM and WM reduction, but only at exploratory statistical thresholds, with no differences remaining after correction for multiple comparisons. Freesurfer analysis demonstrated no group differences. CONCLUSION: NMOSD specific parenchymal brain damage is predominantly located in the optic radiation, likely due to a secondary degeneration caused by ON. In comparison, DTI appears to be the most reliable and sensitive technique for brain damage detection in NMOSD. KEY POINTS: • The hypothesis of a widespread brain damage in NMOSD is challenged. • The optic radiation (OR) is the most severely affected region. • OR-affection is likely due to secondary degeneration following optic neuritis. • DTI is currently the most sensitive technique for NMOSD-related brain-damage detection. • DTI is currently the most reliable technique for NMOSD-related brain-damage detection.


Subject(s)
Brain/diagnostic imaging , Gray Matter/diagnostic imaging , Neuromyelitis Optica/diagnostic imaging , Optic Nerve/diagnostic imaging , White Matter/diagnostic imaging , Adult , Anisotropy , Case-Control Studies , Diffusion Tensor Imaging , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Multimodal Imaging , Tomography, Optical Coherence
2.
Mult Scler ; 21(7): 925-34, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25392321

ABSTRACT

BACKGROUND: Fatigue is one of the most frequent and disabling symptoms in multiple sclerosis, but its pathophysiological mechanisms are poorly understood. It is in particular unclear whether and how fatigue relates to structural and functional brain changes. OBJECTIVE: We aimed to analyse the association of fatigue severity with basal ganglia functional connectivity, basal ganglia volumes, white matter integrity and grey matter density. METHODS: In 44 patients with relapsing-remitting multiple sclerosis and 20 age- and gender-matched healthy controls, resting-state fMRI, diffusion tensor imaging and voxel-based morphometry was performed. RESULTS: In comparison with healthy controls, patients showed alteration of grey matter density, white matter integrity, basal ganglia volumes and basal ganglia functional connectivity. No association of fatigue severity with grey matter density, white matter integrity and basal ganglia volumes was observed within patients. In contrast, fatigue severity was negatively correlated with functional connectivity of basal ganglia nuclei with medial prefrontal cortex, precuneus and posterior cingulate cortex in patients. Furthermore, fatigue severity was positively correlated with functional connectivity between caudate nucleus and motor cortex. CONCLUSION: Fatigue is associated with distinct alterations of basal ganglia functional connectivity independent of overall disability. The pattern of connectivity changes suggests that disruption of motor and non-motor basal ganglia functions, including motivation and reward processing, contributes to fatigue pathophysiology in multiple sclerosis.


Subject(s)
Basal Ganglia/pathology , Fatigue/etiology , Multiple Sclerosis, Relapsing-Remitting/complications , Multiple Sclerosis, Relapsing-Remitting/pathology , Neural Pathways/pathology , Adult , Aged , Diffusion Magnetic Resonance Imaging , Female , Humans , Image Interpretation, Computer-Assisted , Male , Middle Aged
3.
Phys Med Biol ; 53(12): 3147-58, 2008 Jun 21.
Article in English | MEDLINE | ID: mdl-18495979

ABSTRACT

Magnetic resonance elastography (MRE) is an increasingly used noninvasive modality for diagnosing diseases using the response of soft tissue to harmonic shear waves. We present a study on the algebraic Helmholtz inversion (AHI) applied to planar MRE, demonstrating that the deduced phase speed of shear waves depends strongly on the relative orientations of actuator polarization, motion encoding direction and image plane as well as on the actuator plate size, signal-to-noise ratio and discretization of the wave image. Results from the numerical calculation of harmonic elastic waves due to different excitation directions and simulated plate sizes are compared to experiments on a gel phantom. The results suggest that correct phase speed can be obtained despite these largely uncontrollable influences, if AHI is based on out-of-plane displacements and the actuator is driven at an optimal frequency yielding an optimal pixel per wavelength resolution in the wave image. Assuming plane waves, the required number of pixels per wavelength depends only on the degree of noise.


Subject(s)
Algorithms , Elasticity Imaging Techniques/methods , Image Processing, Computer-Assisted/methods , Artifacts , Phantoms, Imaging , Reproducibility of Results
4.
Phys Med Biol ; 52(3): 675-84, 2007 Feb 07.
Article in English | MEDLINE | ID: mdl-17228113

ABSTRACT

A method based on magnetic resonance elastography is presented that allows measuring the weldedness of interfaces between soft tissue layers. The technique exploits the dependence of shear wave scattering at elastic interfaces on the frequency of vibration. Experiments were performed on gel phantoms including differently welded interfaces. Plane wave excitation parallel to the planar interface with corresponding motion sensitization enabled the observation of only shear-horizontal (SH) wave scattering. Spatio-temporal filtering was applied to calculate scattering coefficients from the amplitudes of the incident, transmitted and reflected SH-waves in the vicinity of the interface. The results illustrate that acoustic wave scattering in soft tissues is largely dependent on the connectivity of interfaces, which is potentially interesting for imaging tissue mechanics in medicine and biology.


Subject(s)
Elastic Tissue/anatomy & histology , Magnetic Resonance Imaging/methods , Biophysical Phenomena , Biophysics , Elasticity , Humans , Magnetic Resonance Imaging/instrumentation , Magnetic Resonance Imaging/statistics & numerical data , Models, Theoretical , Phantoms, Imaging
5.
Acta Biomater ; 3(1): 127-37, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17067861

ABSTRACT

Dynamic magnetic resonance elastography (MRE) is a non-invasive method for the quantitative determination of the mechanical properties of soft tissues in vivo. In MRE, shear waves are generated in the tissue and visualized using phase-sensitive MR imaging methods. The resulting two-dimensional (2-D) wave images can reveal in-plane elastic properties when possible geometrical biases of the wave patterns are taken into account. In this study, 3-D MRE experiments of in vivo human brain are analyzed to gain knowledge about the direction of wave propagation and to deduce in-plane elastic properties. The direction of wave propagation was determined using a new algorithm which identifies minimal wave velocities along rays from the surface into the brain. It was possible to quantify biases of the elastic parameters due to projections onto coronal, sagittal and transversal image planes in 2-D MRE. It was found that the in-plane shear modulus is increasingly overestimated when the image slice is displaced from narrow slabs of 2-5cm through the center of the brain. The mean shear modulus of the brain was deduced from 4-D wave data with about 3.5kPa. Using the proposed slice positions in 2-D MRE, this shear modulus can be reproduced with an acceptable error within a fraction of the full 3-D examination time.


Subject(s)
Brain/anatomy & histology , Elasticity , Humans , Phantoms, Imaging , Viscosity
6.
J Neurosurg ; 95(1 Suppl): 93-5, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11453438

ABSTRACT

A case of polymorphous hemangioendothelioma of the spinal cord is described. This 55-year-old woman presented with an 18-month history of lower-extremity sensorimotor deficit. A magnetic resonance image revealed an enhancing, intradural, extramedullary nodule at the T 1-2 level. On gross inspection, the lesion measured 3.5 cm and was firmly attached to spinal cord parenchyma and adjacent nerve roots. It was completely removed. Fourteen months after surgery the patient's neurological deficit had resolved. Polymorphous hemangioendothelioma is a rare vascular tumor of borderline malignancy. Most occur in lymph nodes. None has been reported to occur in the central and peripheral nervous system. Based on current experience, resection and close follow up seems the best therapeutic approach.


Subject(s)
Hemangioendothelioma/surgery , Spinal Cord Neoplasms/surgery , Female , Hemangioendothelioma/diagnosis , Hemangioendothelioma/pathology , Humans , Laminectomy , Magnetic Resonance Imaging , Middle Aged , Spinal Cord/pathology , Spinal Cord/surgery , Spinal Cord Neoplasms/diagnosis , Spinal Cord Neoplasms/pathology , Spinal Nerve Roots/pathology , Spinal Nerve Roots/surgery , Thoracic Vertebrae/pathology , Thoracic Vertebrae/surgery
7.
Am J Clin Nutr ; 70(6): 1077-82, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10584053

ABSTRACT

BACKGROUND: Although several studies showed that risk of rheumatoid arthritis (RA) is inversely associated with consumption of n-3 fatty acids, the one study showing that olive oil may have a protective role has not yet been confirmed. OBJECTIVE: We examined the relation between dietary factors and risk of RA in persons from southern Greece. DESIGN: We studied 145 RA patients and 188 control subjects who provided information on demographic and socioeconomic variables, prior medical and family history, and present disease status. Subjects responded to an interviewer-administered, validated, food-frequency questionnaire that assessed the consumption of >100 food items. We calculated chi-square statistics for linear trend and odds ratios (ORs) for the development of RA in relation to the consumption of olive oil, fish, vegetables, and a series of food groups classified in quartiles. RESULTS: Risk of developing RA was inversely and significantly associated only with cooked vegetables (OR: 0.39) and olive oil (OR: 0.39) by univariate analysis. A significant trend was observed with increasing olive oil (chi-square: 4.28; P = 0.03) and cooked vegetable (chi-square: 10. 48; P = 0.001) consumption. Multiple logistic regression analysis models confirmed the independent and inverse association between olive oil or cooked vegetable consumption and risk of RA (OR: 0.38 and 0.24, respectively). CONCLUSIONS: Consumption of both cooked vegetables and olive oil was inversely and independently associated with risk of RA in this population. Further research is needed to elucidate the underlying mechanisms of this finding, which may include the antioxidant properties or the high n-9 fatty acid content of the olive oil.


Subject(s)
Arthritis, Rheumatoid/prevention & control , Cooking , Diet , Dietary Fats, Unsaturated/administration & dosage , Plant Oils/administration & dosage , Vegetables , Adolescent , Adult , Aged , Aged, 80 and over , Case-Control Studies , Female , Greece , Humans , Male , Middle Aged , Multivariate Analysis , Olive Oil , Surveys and Questionnaires
8.
Acta Med Austriaca ; 26(1): 26-8, 1999.
Article in English | MEDLINE | ID: mdl-10230473

ABSTRACT

The objective of this study was to screen for thyroidopathies in patients with rheumatoid arthritis (RA). Screening for thyroid disorders is advocated in patients with autoimmune diseases, and rheumatoid arthritis has been linked to thyroid autoimmune disorders, more particularly Hashimoto's thyroiditis and sometimes Graves' disease. We performed thyroid disease screening in 69 patients with RA free of medication for at least a 2 weeks period, not in remission, and in 65 patients with osteoarthritis (OA). The latter were studied as a control group of non-autoimmune arthritis patients. Basal levels of thyrotrophin (TSH) were measured using a sensitive chemiluminescence serum TSH assay. Serum antithyroperoxidase and antithyroglobulin (anti-Tg) autoantibodies were measured as well. If TSH values were found to be outside the normal limits, serum total thyroxine, total triiodothyronine (T3), resin T3 uptake, the free thyroxine index (FT4I) and free triiodothyronine index (FT3I) were evaluated. Rheumatoid arthritis patients exhibited statistically significant lower mean TSH values as compared to OA patients. However, RA patients with low TSH values did not have elevated FT4I. Previous use of corticosteroids in some of the RA patients may be responsible for these results. The autoantibodies levels did not differ between the two groups. We conclude that thyroid function screening with sensitive TSH assays is not sufficient for assessment of early stages of autoimmune thyroidopathies in patients with RA. Thyroid hormones should also be estimated.


Subject(s)
Arthritis, Rheumatoid/blood , Arthritis, Rheumatoid/complications , Thyroid Diseases/complications , Thyroid Diseases/diagnosis , Thyrotropin/blood , Female , Humans , Luminescent Measurements , Male , Mass Screening , Middle Aged , Osteoarthritis/blood , Sensitivity and Specificity , Thyroid Diseases/blood , Thyroxine/blood , Triiodothyronine/blood
9.
Am Heart J ; 136(5): 905-12, 1998 Nov.
Article in English | MEDLINE | ID: mdl-9812087

ABSTRACT

BACKGROUND: Morphologic changes of the vascular endothelium are common in patients with systemic sclerosis and Raynaud's phenomenon. The aim of this study was to evaluate the endothelium-dependent vasodilatation and endothelium-independent vasodilatation and to examine the effects of short-term estrogen administration on vascular responses in these patients. METHODS AND RESULTS: The study included 12 female patients with systemic sclerosis and Raynaud's phenomenon (aged 49+/-14 years) and 12 age- and sex-matched healthy control subjects. With the use of high-resolution ultrasound imaging, brachial artery diameter was measured at rest, during reactive hyperemia (endothelium-dependent response), and after administration of sublingual nitroglycerin (endothelium-independent dilatation). Intima-media thickness of the common carotid artery was also measured. Baseline diameter was similar in patients and control subjects; intima-media thickness was significantly higher in patients (0.83+/-0.3 vs 0.46+/-0.2 mm, P= .002) than in control subjects. Flow-mediated dilatation was reduced in patients (3.6%+/-7% vs 11.9%+/- 4.6%, P = .003); endothelium-independent dilatation also was reduced in patients with Raynaud's phenomenon (14%+/-7% vs 23%+/-6%, P= .003). Vascular responses in 10 patients were examined 15 minutes after administration of conjugated estrogens (25 mg intravenously); there was a significant increase of endothelium-dependent dilatation after estrogen administration (1.7%+/-4% to 6.3%+/-4%, P= .01), whereas endothelium-independent dilatation did not change (13.4%+/-8% to 15.5%+/-7%, not significant). CONCLUSIONS: Endothelium-dependent vasodilatation and endothelium-independent vasodilatation are impaired in patients with Raynaud's phenomenon secondary to systemic sclerosis, whereas intima-media thickness is increased. Short-term estrogen administration can improve endothelial dysfunction in this group of patients.


Subject(s)
Endothelium, Vascular/drug effects , Endothelium, Vascular/physiopathology , Estrogens, Conjugated (USP)/therapeutic use , Hormones/therapeutic use , Raynaud Disease/drug therapy , Scleroderma, Systemic/drug therapy , Vasodilation/drug effects , Adult , Aged , Brachial Artery/diagnostic imaging , Carotid Arteries/diagnostic imaging , Case-Control Studies , Drug Administration Schedule , Female , Humans , Middle Aged , Raynaud Disease/diagnostic imaging , Scleroderma, Systemic/diagnostic imaging , Ultrasonography
10.
Br J Rheumatol ; 37(9): 937-45, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9783757

ABSTRACT

Although widely used, non-steroidal anti-inflammatory drugs (NSAIDs) are associated with a high incidence of gastrointestinal (GI) side-effects. Inhibition of the cyclooxygenase (COX) enzyme is the basis for both the efficacy and toxicity of NSAIDs. The discovery of two COX isoforms, constitutive COX-1 and inducible COX-2, has led to the hypothesis that selective inhibition of COX-2 will minimize the potential for GI toxicity without compromising efficacy. The Meloxicam Large-scale International Study Safety Assessment (MELISSA) trial reported here was therefore set up to investigate the tolerability of meloxicam, a preferential inhibitor of COX-2, compared to diclofenac. MELISSA was a large-scale, double-blind, randomized, international, prospective trial, conducted over 28 days in patients with symptomatic osteoarthritis. Patients received either meloxicam 7.5 mg or diclofenac 100 mg slow release, the recommended doses for the treatment of osteoarthritis. Evaluation of the profile of adverse events was the main aim of the trial, together with assessment of efficacy. A total of 9323 patients received treatment (4635 and 4688 in the meloxicam and diclofenac groups, respectively). Significantly fewer adverse events were reported by patients receiving meloxicam. This was attributable to fewer GI adverse events (13%) compared to diclofenac (19%; P < 0.001). Of the most common GI adverse events, there was significantly less dyspepsia (P < 0.001), nausea and vomiting (P < 0.05), abdominal pain (P < 0.001) and diarrhoea (P < 0.001) with meloxicam compared to diclofenac. Five patients on meloxicam experienced a perforation, ulcer or bleed vs seven on diclofenac (not significant). No endoscopically verified ulcer complication was detected in the meloxicam group compared to four with diclofenac. There were five patient days of hospitalization in patients on meloxicam compared to 121 with diclofenac. Adverse events caused withdrawal from the study in 254 patients receiving meloxicam (5.48%) compared to 373 (7.96%) on diclofenac (P < 0.001). These differences were attributable to differences in reported GI adverse events (3.02% on meloxicam vs 6.14% on diclofenac; P < 0.001). Differences in efficacy, as assessed by visual analogue scales, consistently favoured diclofenac. In all instances, 95% confidence intervals did not cross zero, suggesting a statistically significant effect. However, differences were small (4.5-9.01% difference) and did not reach pre-determined levels of clinical significance. Nevertheless, significantly more patients discontinued meloxicam because of lack of efficacy (80 out of 4635 vs 49 out of 4688; P < 0.01). The MELISSA trial confirms earlier studies suggesting that meloxicam has a significantly improved GI tolerability profile in comparison with other NSAIDs, including diclofenac. These results may in part reflect the preferential COX-2 selectivity of meloxicam, although the dose and other aspects of tolerability may be important. These results may provide support for the hypothesis that selective inhibition of COX-2 relative to COX-1 might be an effective approach towards improved NSAID therapy.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Cyclooxygenase Inhibitors/adverse effects , Diclofenac/adverse effects , Gastrointestinal Diseases/chemically induced , Osteoarthritis/drug therapy , Thiazines/adverse effects , Thiazoles/adverse effects , Aged , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Cyclooxygenase Inhibitors/therapeutic use , Diclofenac/therapeutic use , Double-Blind Method , Female , Gastrointestinal Diseases/classification , Gastrointestinal Hemorrhage/chemically induced , Humans , Isoenzymes/antagonists & inhibitors , Male , Meloxicam , Middle Aged , Patient Dropouts/statistics & numerical data , Peptic Ulcer/chemically induced , Prospective Studies , Thiazines/therapeutic use , Thiazoles/therapeutic use , Treatment Outcome
11.
Br J Rheumatol ; 37(9): 946-51, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9783758

ABSTRACT

SELECT is a large-scale, prospective, international, multicentre, double-blind, double-dummy, randomized, parallel-group trial. Patients with exacerbation of osteoarthritis were treated with the recommended dose of meloxicam (7.5 mg) or piroxicam (20 mg) once daily for 28 days; 4320 patients were administered meloxicam and 4336 piroxicam. The incidence of adverse events was significantly lower in the meloxicam group (22.5%) compared with the piroxicam group (27.9%; P < 0.001), mainly due to the significantly lower incidence of gastrointestinal (GI) adverse events in the meloxicam than in the piroxicam group (10.3% vs 15.4%,; P < 0.001), while the efficacy of both drugs was equivalent. Individual GI events occurred significantly less often with meloxicam than piroxicam: dyspepsia (3.4% vs 5.8%; P < 0.001), nausea/vomiting (2.5% vs 3.4%; P < 0.05) and abdominal pain (2.1% vs 3.6%; P < 0.001). There were 16 patients with perforations, ulcerations or bleeding (PUBs) of the upper GI tract in the piroxicam group compared with seven in the meloxicam group (relative risk piroxicam:meloxicam = 1.4). Four PUBs were complicated (perforations or bleedings); none of these occurred in the meloxicam group (relative risk piroxicam:meloxicam = 1.9). The outcome of SELECT is consistent with that of the large-scale clinical trial of similar design and size which compared 7.5 mg meloxicam with 100 mg diclofenac in patients with osteoarthritis, and with a previous global analysis of the safety of meloxicam. It adds further data to the proposed relationship between selective inhibition of cyclooxygenase-2 and improved GI tolerability of non-steroidal anti-inflammatory drugs.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Cyclooxygenase Inhibitors/adverse effects , Gastrointestinal Diseases/chemically induced , Osteoarthritis/drug therapy , Piroxicam/adverse effects , Thiazines/adverse effects , Thiazoles/adverse effects , Aged , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Cyclooxygenase Inhibitors/therapeutic use , Double-Blind Method , Female , Humans , Isoenzymes/antagonists & inhibitors , Male , Meloxicam , Middle Aged , Piroxicam/therapeutic use , Prospective Studies , Thiazines/therapeutic use , Thiazoles/therapeutic use , Treatment Outcome
12.
Clin Exp Rheumatol ; 16(2): 135-40, 1998.
Article in English | MEDLINE | ID: mdl-9536388

ABSTRACT

OBJECTIVE: Cardiac involvement with myocardial-band necrosis is common in systemic sclerosis. One possible explanation is that an underlying vasomotor abnormality accounts for these histologic findings. To shed light on this issue we investigated the existence of "myocardial Raynaud's phenomenon" in such patients. METHODS: We examined 25 patients with systemic sclerosis and 14 patients with systemic lupus erythematosus or rheumatoid arthritis, using cold pressor and dipyridamole-thallium-201 scintigraphy. RESULTS: Twenty-three patients with systemic sclerosis and 13 patients with lupus erythematosus or rheumatoid arthritis had normal perfusion during dipyridamole imaging. Seven scleroderma patients with normal dipyridamole test presented cold-induced transient myocardial ischemia, while none of the control patients had cold-induced ischemia (p = 0.034). All patients with cold-induced ischemic defects presented long-standing Raynaud's phenomenon (> 5 years); of the 14 patients with long-standing Raynaud's phenomenon 7 presented ischemic thallium-201 defects; of the remaining 9 patients with Raynaud's phenomenon of short duration (< 5 years) none presented cold-induced ischemia (p = 0.019). CONCLUSION: Patients with systemic sclerosis and long-standing Raynaud's phenomenon, even in the presence of normal myocardial perfusion during pharmacological vasodilation with dipyridamole, may present cold-induced myocardial ischemia, a functional Raynaud's phenomenon of the heart.


Subject(s)
Cold Temperature , Coronary Vessels/physiopathology , Raynaud Disease/physiopathology , Scleroderma, Systemic/physiopathology , Adult , Aged , Coronary Circulation/physiology , Coronary Vessels/diagnostic imaging , Dipyridamole , Female , Humans , Lupus Erythematosus, Systemic/physiopathology , Male , Middle Aged , Thallium Radioisotopes , Tomography, Emission-Computed, Single-Photon
13.
Angiology ; 48(2): 135-9, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9040268

ABSTRACT

The purpose of this study was to delineate among the usually gathered parameters in an electrocardiographic exercise test the determinants of its positive outcome (delta ST decreases > or = 1 mm measured at 80 msec from the J point). The authors studied 832 patients investigated with Bruce's exercise testing and with diagnostic coronary arteriography, all of whom were shown to have significant coronary artery disease (diameter stenosis > or = 50%). Twenty-five demographic, clinical, electrocardiographic, exercise, and anatomic/hemodynamic parameters were analyzed. The stepwise forward logistic regression analysis retained seven among them as significant independent predictors: four as positive contributors: (1) three-vessel and/or left main disease (P = 0.0000), (2) Gensini's angio-graphic score for disease extent (P = 0.0025), (3) anginal pain during the test (P = 0.0000), and (4) age (P = 0.0031) and three as negative contributors: (1) resting heart rate (P = 0.0004), (2) history of old myocardial infarction (P = 0.0019), and (3) pathological Q waves at the resting ECG (P = 0.0018). These findings establish standards that permit the prediction of the positive electrocardiographic exercise outcome in patients with significant coronary disease.


Subject(s)
Coronary Disease/diagnosis , Electrocardiography , Exercise Test , Constriction, Pathologic , Female , Heart Rate , Humans , Logistic Models , Male , Middle Aged , Predictive Value of Tests
14.
Clin Exp Rheumatol ; 14(6): 613-7, 1996.
Article in English | MEDLINE | ID: mdl-8978955

ABSTRACT

OBJECTIVES: To assess whether plasma renin activity (PRA) in patients with rheumatoid arthritis (RA) and evidence of renal involvement (microhematuria) can serve as potential marker of renovascular injury. METHODS: PRA was measured at rest and following exercise. All nonsteroidal antiinflammatory drugs or other medications that might affect renin release were stopped at least ten days prior to PRA measurements. PRA was correlated with the number of dysmorphic erythrocytes present in the urine sediment as indicators of glomerular capillary injury (microhematuria). RESULTS: All patients with RA had a higher mean PRA than controls. Moreover, all patients with RA in whom microhematuria was present had a higher PRA than those without microhematuria. Simple and multiple regression analysis revealed a significant correlation between: a) PRA and rheumatoid factor levels; b) rheumatoid factor levels and the number of erythrocytes in the urine sediment; and c) PRA levels and the number of erythrocytes in the urine sediment. CONCLUSIONS: The observations indicate that increased PRA may occur in normotensive patients with RA and no clinical or biochemical evidence of renal involvement. This may reflect activation of the renin-angiotensin system. The positive correlation between enhanced PRA, rheumatoid factor levels and microhematuria in RA patients may indicate inflammatory injury of the glomerular microvasculature involving the juxtaglomerular apparatus.


Subject(s)
Arthritis, Rheumatoid/blood , Biomarkers/blood , Glomerulonephritis/pathology , Hematuria/etiology , Juxtaglomerular Apparatus/pathology , Renin/blood , Adult , Aged , Arthritis, Rheumatoid/complications , Female , Hematuria/blood , Hematuria/diagnostic imaging , Humans , Male , Middle Aged , Radioimmunoassay , Regression Analysis , Rheumatoid Factor/blood , Ultrasonography
15.
Ann Rheum Dis ; 55(3): 187-9, 1996 Mar.
Article in English | MEDLINE | ID: mdl-8712882

ABSTRACT

OBJECTIVE: To report clinical experience from patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) who were receiving recommended doses of hydroxychloroquine for more than six years, and were monitored for evidence of hydroxychloroquine related retinopathy every six months. METHODS: A prospective (and continuing) evaluation was made of the potential retinal toxicity of hydroxychloroquine in a cohort of 360 Greek patients followed for RA and SLE, 58 of whom have received long term treatment ( > six years). Fundoscopy, colour vision tests, dark adaptation tests, visual field testing, automated perimetry, and electroretinogram were performed every six months. RESULTS: Among 58 patients receiving hydroxychloroquine for more than six years, two relatively young women (3.5%), one treated for RA and the other treated for SLE, developed characteristic hydroxychloroquine related toxic retinal lesions after cumulative doses of 700 g (6.5 years) and 730 g (8 years) of hydroxychloroquine, respectively. Bilateral visual acuity was 6/6 and 6/7.5, respectively; both patients had normal colour perception. Despite an early diagnosis and cessation of treatment, permanent visual field paracentral scotomata in both patients, and persisting lesions in fluorescein angiography in the patient with SLE, were observed at 4.5 and 3 years of follow up, respectively. No other specific cases of hydroxychloroquine related retinopathy have to date been identified in the remaining 302 patients. CONCLUSION: Cases of irreversible, hydroxychloroquine related retinopathy in patients who did not receive overdoses have not been reported previously. The present observations in two relatively young patients should raise our concern regarding the long term usage of an increasingly popular medication in rheumatology practice.


Subject(s)
Antimalarials/adverse effects , Hydroxychloroquine/adverse effects , Retina/drug effects , Adult , Arthritis, Rheumatoid/drug therapy , Female , Fluorescein Angiography , Humans , Lupus Erythematosus, Systemic/drug therapy , Male , Middle Aged , Prospective Studies , Visual Acuity/drug effects
16.
Arthritis Rheum ; 33(11): 1634-9, 1990 Nov.
Article in English | MEDLINE | ID: mdl-2242061

ABSTRACT

Lung involvement in systemic sclerosis may be due in part to a functional abnormality of the pulmonary vasculature. To investigate the possible role of a pulmonary vasospastic process in this disorder, 21 non-smoking patients who had no evidence of cardiac disease or pulmonary hypertension were evaluated with pulmonary function tests prior to administration of nifedipine, 30 minutes after a single oral dose of nifedipine (20 mg), and after 4 weeks of treatment with nifedipine (10 mg 3 times daily). Treatment with nifedipine did not significantly change any of the pulmonary function values, except for the carbon monoxide diffusing capacity (DLCO). The linear trend between the individual DLCO values at baseline and their changes immediately following the initial 20-mg dose of nifedipine (r = -0.603, P = 0.02) and after 4 weeks of treatment (r = -0.636, P = 0.01) showed that the lower the DLCO value at baseline, the greater the improvement caused by nifedipine. These findings support the hypothesis of a potentially reversible pulmonary vasospasm in systemic sclerosis and suggest that nifedipine may be useful in the treatment of lung disease in these patients; however, further studies are needed.


Subject(s)
Nifedipine/pharmacology , Pulmonary Diffusing Capacity/drug effects , Scleroderma, Systemic/physiopathology , Adult , Carbon Monoxide/metabolism , Drug Administration Schedule , Female , Hemodynamics/drug effects , Humans , Lung Diseases/etiology , Lung Diseases/physiopathology , Male , Middle Aged , Nifedipine/administration & dosage , Respiratory Function Tests , Scleroderma, Systemic/complications , Spasm/etiology , Spasm/physiopathology , Vascular Diseases/etiology , Vascular Diseases/physiopathology
17.
J Immunol ; 133(6): 3387-95, 1984 Dec.
Article in English | MEDLINE | ID: mdl-6238097

ABSTRACT

We have examined the ability of cultured human glioma cells to elicit allogeneic cytolytic lymphocyte responses in vitro in order to delineate properties of glioma cells that may contribute to their ability to escape cellular immune attack. When glioma cells were cultured together with allogeneic peripheral blood mononuclear cells (PBMC) in mixed lymphocyte-tumor cultures (MLTC), it was observed that cells from eight of 12 glioma lines were surrounded by clear pericellular "halos," which appeared to impede contact between PBMC and the glioma cells. Enzymatic, histochemical, and immunochemical studies indicated that these halos represented glycosaminoglycan (GAG) coats that contained hyaluronic acid (HA) as a major constituent. Electron microscopic studies demonstrated the presence of many thin microvillous processes spanning the width of the halos. The presence of GAG coats around glioma cells in MLTC reduced the generation of cytolytic T lymphocytes specific for antigens on the glioma cells. Likewise, these cell coats decreased the lysis of glioma cells by cytolytic lymphocytes, once generated. The production of thick coats of GAG by glioma cells was induced by interaction of glioma cells with a nondialyzable factor produced by PBMC in culture. This factor did not cause glioma cells to release increased amounts of HA into the medium, but rather increased the production of HA that remained associated with the glioma cell surface. The formation of thick, protective GAG coats by glioma cells as a result of their interaction with the PBMC-derived factor constitutes a nonspecific suppressor mechanism that may contribute to the ability of this class of human solid tumors to evade cellular immune attack.


Subject(s)
Brain Neoplasms/immunology , Glioma/immunology , Glycosaminoglycans/biosynthesis , Leukocytes/immunology , Brain Neoplasms/metabolism , Brain Neoplasms/ultrastructure , Cell Line , Cell Membrane/metabolism , Cell Membrane/ultrastructure , Glioma/metabolism , Glioma/ultrastructure , Humans , Hyaluronic Acid/metabolism , Immunity, Cellular , Leukocytes/metabolism , Lymphocyte Activation , Lymphocyte Culture Test, Mixed , T-Lymphocytes, Cytotoxic/immunology
18.
J Surg Oncol ; 25(4): 227-31, 1984 Apr.
Article in English | MEDLINE | ID: mdl-6717019

ABSTRACT

Neuroblastoma is a common solid tumor of childhood. Maturation to a ganglioneuroma or regression has been reported to occur spontaneously or following minimal treatment. Malignant degeneration of such a ganglioneuroma is extremely rare. We present a report of a malignant tumor arising in a ganglioneuroma 19 years following abdominal radiation therapy for neuroblastoma.


Subject(s)
Abdominal Neoplasms/pathology , Ganglioneuroma/pathology , Muscular Diseases/pathology , Neuroblastoma/pathology , Abdominal Neoplasms/radiotherapy , Adult , Female , Humans , Infant , Neuroblastoma/radiotherapy , Splenic Neoplasms/radiotherapy , Time Factors
19.
Science ; 220(4598): 739-42, 1983 May 13.
Article in English | MEDLINE | ID: mdl-6220469

ABSTRACT

Certain human glioma lines produce mucopolysaccharide coats that impair the generation of cytolytic lymphocytes in response to these lines in vitro. Coat production is substantially enhanced by the interaction of glioma cells with a macromolecular factor released by human peripheral blood mononuclear cells in culture. This interaction thus constitutes an unusual mechanism by which inflammatory cells may nonspecifically suppress the cellular immune response to at least one class of solid tumors in humans.


Subject(s)
Glioma/metabolism , Lymphocytes/metabolism , Animals , Cell Line , Cytotoxicity, Immunologic , Glioma/immunology , Glycosaminoglycans/biosynthesis , Humans , Hyaluronoglucosaminidase/metabolism , Immunity, Cellular , Lymphocytes/immunology , Mice , Rabbits
20.
Immunology ; 41(1): 37-43, 1980 Sep.
Article in English | MEDLINE | ID: mdl-6903558

ABSTRACT

Monocytes, synovial fluid (SF) and synovial membrane (SM) macrophages from patients with rheumatoid arthritis (RA) were maintained in short-term tissue culture for up to 10 days, and the synthesis of C4, C2, C3, C5, factor B(B), D, properdin (P), C3b inactivator (C3bINA) and beta 1H globulin studied. Functionally active C2, B, D, P, C3bINA and beta 1H were synthesized by the cells in each type of culture. C4, C3 and C5 could be detected, but were functionally inactive. RA monocytes synthesized more C2 than monocytes from patients with degenerative joint disease (DJD) (P < 0.001). Similar studies revealed that SF macrophages synthesized more C3 than SM macrophages (P < 0.001) which in turn produced more C2 than monocytes (P < 0.001). Other experiments showed that SF macrophages synthesized more of each component than the other cell types. SM macrophages made more C2 than B than RA and DJD monocytes, but synthesized only small quantities of P, D and beta 1H. RA monocytes synthesized more of each component than DJD monocytes. The results of these studies show that (1) in RA, complement components can be synthesized locally in the inflamed joints, and (2) local factors in the joints probably stimulate complement synthesis.


Subject(s)
Arthritis, Rheumatoid/immunology , Complement System Proteins/biosynthesis , Cells, Cultured , Complement C2/biosynthesis , Complement C3b Inactivator Proteins/biosynthesis , Complement Factor B/biosynthesis , Humans , Macrophages/immunology , Monocytes/immunology , Properdin/biosynthesis , Synovial Fluid/immunology , Synovial Membrane/immunology
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