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1.
Eur Radiol ; 26(12): 4413-4422, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27012555

RESUMO

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.


Assuntos
Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Neuromielite Óptica/diagnóstico por imagem , Nervo Óptico/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Anisotropia , Estudos de Casos e Controles , Imagem de Tensor de Difusão , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Tomografia de Coerência Óptica
2.
Mult Scler ; 21(7): 925-34, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25392321

RESUMO

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.


Assuntos
Gânglios da Base/patologia , Fadiga/etiologia , Esclerose Múltipla Recidivante-Remitente/complicações , Esclerose Múltipla Recidivante-Remitente/patologia , Vias Neurais/patologia , Adulto , Idoso , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade
3.
Phys Med Biol ; 53(12): 3147-58, 2008 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-18495979

RESUMO

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.


Assuntos
Algoritmos , Técnicas de Imagem por Elasticidade/métodos , Processamento de Imagem Assistida por Computador/métodos , Artefatos , Imagens de Fantasmas , Reprodutibilidade dos Testes
4.
Phys Med Biol ; 52(3): 675-84, 2007 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-17228113

RESUMO

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.


Assuntos
Tecido Elástico/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Fenômenos Biofísicos , Biofísica , Elasticidade , Humanos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/estatística & dados numéricos , Modelos Teóricos , Imagens de Fantasmas
5.
Acta Biomater ; 3(1): 127-37, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17067861

RESUMO

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.


Assuntos
Encéfalo/anatomia & histologia , Elasticidade , Humanos , Imagens de Fantasmas , Viscosidade
6.
J Neurosurg ; 95(1 Suppl): 93-5, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11453438

RESUMO

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.


Assuntos
Hemangioendotelioma/cirurgia , Neoplasias da Medula Espinal/cirurgia , Feminino , Hemangioendotelioma/diagnóstico , Hemangioendotelioma/patologia , Humanos , Laminectomia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Medula Espinal/patologia , Medula Espinal/cirurgia , Neoplasias da Medula Espinal/diagnóstico , Neoplasias da Medula Espinal/patologia , Raízes Nervosas Espinhais/patologia , Raízes Nervosas Espinhais/cirurgia , Vértebras Torácicas/patologia , Vértebras Torácicas/cirurgia
7.
Am J Clin Nutr ; 70(6): 1077-82, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10584053

RESUMO

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.


Assuntos
Artrite Reumatoide/prevenção & controle , Culinária , Dieta , Gorduras Insaturadas na Dieta/administração & dosagem , Óleos de Plantas/administração & dosagem , Verduras , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Grécia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Azeite de Oliva , Inquéritos e Questionários
8.
Acta Med Austriaca ; 26(1): 26-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10230473

RESUMO

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.


Assuntos
Artrite Reumatoide/sangue , Artrite Reumatoide/complicações , Doenças da Glândula Tireoide/complicações , Doenças da Glândula Tireoide/diagnóstico , Tireotropina/sangue , Feminino , Humanos , Medições Luminescentes , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Osteoartrite/sangue , Sensibilidade e Especificidade , Doenças da Glândula Tireoide/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
9.
Am Heart J ; 136(5): 905-12, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9812087

RESUMO

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.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Estrogênios Conjugados (USP)/uso terapêutico , Hormônios/uso terapêutico , Doença de Raynaud/tratamento farmacológico , Escleroderma Sistêmico/tratamento farmacológico , Vasodilatação/efeitos dos fármacos , Adulto , Idoso , Artéria Braquial/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Estudos de Casos e Controles , Esquema de Medicação , Feminino , Humanos , Pessoa de Meia-Idade , Doença de Raynaud/diagnóstico por imagem , Escleroderma Sistêmico/diagnóstico por imagem , Ultrassonografia
10.
Br J Rheumatol ; 37(9): 937-45, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9783757

RESUMO

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.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Inibidores de Ciclo-Oxigenase/efeitos adversos , Diclofenaco/efeitos adversos , Gastroenteropatias/induzido quimicamente , Osteoartrite/tratamento farmacológico , Tiazinas/efeitos adversos , Tiazóis/efeitos adversos , Idoso , Anti-Inflamatórios não Esteroides/uso terapêutico , Inibidores de Ciclo-Oxigenase/uso terapêutico , Diclofenaco/uso terapêutico , Método Duplo-Cego , Feminino , Gastroenteropatias/classificação , Hemorragia Gastrointestinal/induzido quimicamente , Humanos , Isoenzimas/antagonistas & inibidores , Masculino , Meloxicam , Pessoa de Meia-Idade , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Úlcera Péptica/induzido quimicamente , Estudos Prospectivos , Tiazinas/uso terapêutico , Tiazóis/uso terapêutico , Resultado do Tratamento
11.
Br J Rheumatol ; 37(9): 946-51, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9783758

RESUMO

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.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Inibidores de Ciclo-Oxigenase/efeitos adversos , Gastroenteropatias/induzido quimicamente , Osteoartrite/tratamento farmacológico , Piroxicam/efeitos adversos , Tiazinas/efeitos adversos , Tiazóis/efeitos adversos , Idoso , Anti-Inflamatórios não Esteroides/uso terapêutico , Inibidores de Ciclo-Oxigenase/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Isoenzimas/antagonistas & inibidores , Masculino , Meloxicam , Pessoa de Meia-Idade , Piroxicam/uso terapêutico , Estudos Prospectivos , Tiazinas/uso terapêutico , Tiazóis/uso terapêutico , Resultado do Tratamento
12.
Clin Exp Rheumatol ; 16(2): 135-40, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9536388

RESUMO

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.


Assuntos
Temperatura Baixa , Vasos Coronários/fisiopatologia , Doença de Raynaud/fisiopatologia , Escleroderma Sistêmico/fisiopatologia , Adulto , Idoso , Circulação Coronária/fisiologia , Vasos Coronários/diagnóstico por imagem , Dipiridamol , Feminino , Humanos , Lúpus Eritematoso Sistêmico/fisiopatologia , Masculino , Pessoa de Meia-Idade , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão de Fóton Único
13.
Angiology ; 48(2): 135-9, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9040268

RESUMO

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.


Assuntos
Doença das Coronárias/diagnóstico , Eletrocardiografia , Teste de Esforço , Constrição Patológica , Feminino , Frequência Cardíaca , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes
14.
Clin Exp Rheumatol ; 14(6): 613-7, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8978955

RESUMO

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.


Assuntos
Artrite Reumatoide/sangue , Biomarcadores/sangue , Glomerulonefrite/patologia , Hematúria/etiologia , Sistema Justaglomerular/patologia , Renina/sangue , Adulto , Idoso , Artrite Reumatoide/complicações , Feminino , Hematúria/sangue , Hematúria/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , Análise de Regressão , Fator Reumatoide/sangue , Ultrassonografia
15.
Ann Rheum Dis ; 55(3): 187-9, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8712882

RESUMO

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.


Assuntos
Antimaláricos/efeitos adversos , Hidroxicloroquina/efeitos adversos , Retina/efeitos dos fármacos , Adulto , Artrite Reumatoide/tratamento farmacológico , Feminino , Angiofluoresceinografia , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Acuidade Visual/efeitos dos fármacos
16.
Arthritis Rheum ; 33(11): 1634-9, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2242061

RESUMO

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.


Assuntos
Nifedipino/farmacologia , Capacidade de Difusão Pulmonar/efeitos dos fármacos , Escleroderma Sistêmico/fisiopatologia , Adulto , Monóxido de Carbono/metabolismo , Esquema de Medicação , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Pneumopatias/etiologia , Pneumopatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Nifedipino/administração & dosagem , Testes de Função Respiratória , Escleroderma Sistêmico/complicações , Espasmo/etiologia , Espasmo/fisiopatologia , Doenças Vasculares/etiologia , Doenças Vasculares/fisiopatologia
17.
J Immunol ; 133(6): 3387-95, 1984 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6238097

RESUMO

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.


Assuntos
Neoplasias Encefálicas/imunologia , Glioma/imunologia , Glicosaminoglicanos/biossíntese , Leucócitos/imunologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/ultraestrutura , Linhagem Celular , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Glioma/metabolismo , Glioma/ultraestrutura , Humanos , Ácido Hialurônico/metabolismo , Imunidade Celular , Leucócitos/metabolismo , Ativação Linfocitária , Teste de Cultura Mista de Linfócitos , Linfócitos T Citotóxicos/imunologia
18.
J Surg Oncol ; 25(4): 227-31, 1984 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6717019

RESUMO

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.


Assuntos
Neoplasias Abdominais/patologia , Ganglioneuroma/patologia , Doenças Musculares/patologia , Neuroblastoma/patologia , Neoplasias Abdominais/radioterapia , Adulto , Feminino , Humanos , Lactente , Neuroblastoma/radioterapia , Neoplasias Esplênicas/radioterapia , Fatores de Tempo
19.
Science ; 220(4598): 739-42, 1983 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-6220469

RESUMO

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.


Assuntos
Glioma/metabolismo , Linfócitos/metabolismo , Animais , Linhagem Celular , Citotoxicidade Imunológica , Glioma/imunologia , Glicosaminoglicanos/biossíntese , Humanos , Hialuronoglucosaminidase/metabolismo , Imunidade Celular , Linfócitos/imunologia , Camundongos , Coelhos
20.
Immunology ; 41(1): 37-43, 1980 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6903558

RESUMO

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.


Assuntos
Artrite Reumatoide/imunologia , Proteínas do Sistema Complemento/biossíntese , Células Cultivadas , Complemento C2/biossíntese , Proteínas Inativadoras do Complemento C3b/biossíntese , Fator B do Complemento/biossíntese , Humanos , Macrófagos/imunologia , Monócitos/imunologia , Properdina/biossíntese , Líquido Sinovial/imunologia , Membrana Sinovial/imunologia
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