Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Rev Med Chil ; 142(11): 1371-6, 2014 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-25694281

RESUMO

BACKGROUND: An adequate sleeping pattern recovers physical and mental wellbeing and improves mood. AIM: To determine the association between quality of life and quantity of sleep in older people living in Santiago and Viña del Mar, Chile. MATERIAL AND METHODS: The Spanish versions of the Health Promoting Lifestyles survey and the Pittsburgh Sleep Quality Index were answered by 975 non-disabled participants aged 70.7 ± 7.4 years (61% females). RESULTS: Older adults who slept < 7.0 or > 8.5 hours (h) per night were at higher risk of having lower quality of life scores for all sub-domains, compared with those that slept 7.0 to 8.5 h per night. CONCLUSIONS: A normal sleep pattern in older adults is associated with a better quality of life perception.


Assuntos
Qualidade de Vida , Sono/fisiologia , Fatores Etários , Idoso , Análise de Variância , Chile , Estudos Transversais , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fatores de Risco , Autorrelato , Fatores de Tempo
2.
Neuroimage Clin ; 42: 103590, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38513535

RESUMO

BACKGROUND: Apical ground-glass opacification (GGO) identified on CT angiography (CTA) performed for suspected acute stroke was developed in 2020 as a coronavirus-disease-2019 (COVID-19) diagnostic and prognostic biomarker in a retrospective study during the first wave of COVID-19. OBJECTIVE: To prospectively validate whether GGO on CTA performed for suspected acute stroke is a reliable COVID-19 diagnostic and prognostic biomarker and whether it is reliable for COVID-19 vaccinated patients. METHODS: In this prospective, pragmatic, national, multi-center validation study performed at 13 sites, we captured study data consecutively in patients undergoing CTA for suspected acute stroke from January-March 2021. Demographic and clinical features associated with stroke and COVID-19 were incorporated. The primary outcome was the likelihood of reverse-transcriptase-polymerase-chain-reaction swab-test-confirmed COVID-19 using the GGO biomarker. Secondary outcomes investigated were functional status at discharge and survival analyses at 30 and 90 days. Univariate and multivariable statistical analyses were employed. RESULTS: CTAs from 1,111 patients were analyzed, with apical GGO identified in 8.5 % during a period of high COVID-19 prevalence. GGO showed good inter-rater reliability (Fleiss κ = 0.77); and high COVID-19 specificity (93.7 %, 91.8-95.2) and negative predictive value (NPV; 97.8 %, 96.5-98.6). In subgroup analysis of vaccinated patients, GGO remained a good diagnostic biomarker (specificity 93.1 %, 89.8-95.5; NPV 99.7 %, 98.3-100.0). Patients with COVID-19 were more likely to have higher stroke score (NIHSS (mean +/- SD) 6.9 +/- 6.9, COVID-19 negative, 9.7 +/- 9.0, COVID-19 positive; p = 0.01), carotid occlusions (6.2 % negative, 14.9 % positive; p = 0.02), and larger infarcts on presentation CT (ASPECTS 9.4 +/- 1.5, COVID-19 negative, 8.6 +/- 2.4, COVID-19 positive; p = 0.00). After multivariable logistic regression, GGO (odds ratio 15.7, 6.2-40.1), myalgia (8.9, 2.1-38.2) and higher core body temperature (1.9, 1.1-3.2) were independent COVID-19 predictors. GGO was associated with worse functional outcome on discharge and worse survival after univariate analysis. However, after adjustment for factors including stroke severity, GGO was not independently predictive of functional outcome or mortality. CONCLUSION: Apical GGO on CTA performed for patients with suspected acute stroke is a reliable diagnostic biomarker for COVID-19, which in combination with clinical features may be useful in COVID-19 triage.


Assuntos
COVID-19 , Angiografia por Tomografia Computadorizada , Acidente Vascular Cerebral , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores , Angiografia por Tomografia Computadorizada/métodos , COVID-19/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Prognóstico , Estudos Prospectivos , SARS-CoV-2 , Acidente Vascular Cerebral/diagnóstico por imagem
3.
Immunopharmacol Immunotoxicol ; 32(4): 620-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20184429

RESUMO

The anti-inflammatory drugs possess many serious side effects at doses commonly prescribed. It is really important to discover novel regulators of inflammation from natural sources with minimal adverse effects. Schinus areira L. is a plant native from South America and is used in folk medicine as an anti-inflammatory herb. For this study, the activity of aqueous extracts on inflammation and the effect on superoxide anion production in mice macrophages were assayed. Aqueous extracts were prepared by soaking herbs in cold water (cold extract), boiling water (infusion), and simmering water (decoction). Cold extract possess an anti-inflammatory activity. Decoction and infusion showed pro-inflammatory activity. Cold extract increased the production of superoxide anion. It has been proposed to use diverse methods to obtain extracts of S. areira L. with different effects. Cold extract, decoction, and infusion could be utilized as extracts or as pharmacological preparations for topical application.


Assuntos
Anacardiaceae/química , Anti-Inflamatórios/farmacologia , Mediadores da Inflamação/farmacologia , Inflamação/induzido quimicamente , Inflamação/prevenção & controle , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/uso terapêutico , Sangue/efeitos dos fármacos , Carragenina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Orelha/patologia , Edema/induzido quimicamente , Edema/patologia , Edema/prevenção & controle , Feminino , Pé/patologia , Inflamação/patologia , Mediadores da Inflamação/administração & dosagem , Mediadores da Inflamação/isolamento & purificação , Interleucina-10/sangue , Interleucina-6/sangue , Interleucina-6/metabolismo , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Componentes Aéreos da Planta/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Explosão Respiratória/efeitos dos fármacos , Explosão Respiratória/imunologia , Superóxidos/metabolismo , Acetato de Tetradecanoilforbol/administração & dosagem , Acetato de Tetradecanoilforbol/farmacologia , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismo , Zimosan/imunologia , Zimosan/farmacologia
4.
Nephron Physiol ; 101(4): p82-91, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16113589

RESUMO

BACKGROUND: Several salutary biological effects of statins have been described. We sought to investigate more closely the anti-inflammatory and antiproliferative effects of simvastatin (SIMV) in a model of hypertension and progressive renal disease, as well as its effects on the cyclin-cdk inhibitors p21 and p27. METHODS: Munich-Wistar rats received the nitric oxide (NO) synthase inhibitor L-NAME (25 mg/kg/day p.o.) for 20 days accompanied by a high-salt diet (HS, 3% Na) and then were kept on HS for 60 days. Animals were then divided into two groups: vehicle (VH) or SIMV 2 mg/kg/day p.o. Albuminuria and tail-cuff pressure were determined at 30 and 60 days. RT-PCR was done to assess renal expression of TGF-beta1, collagen I and III, fibronectin, p27, p21 and monocyte chemoattractant protein-1 (MCP-1). Renal protein expression was assessed by Western blot (proliferating cell nuclear antigen (PCNA)) and immunostaining (macrophage, lymphocyte, PCNA). RESULTS: SIMV did not prevent the development of severe hypertension or albuminuria. SIMV-treated animals had less severe renal interstitial inflammation and cell proliferation. MCP-1 expression was significantly diminished in the SIMV-treated animals (55.4 +/- 7.3 vs. 84.4 +/- 8.2 OD, p = 0.02). mRNA renal expression for p27 and TGF-beta did not change between groups, but p21 mRNA renal expression, highly induced in this model, significantly decreased with SIMV treatment (31.6 +/- 6.6 vs. 50.2 +/- 5.8 OD, p < 0.05). The interstitial fibrosis score significantly decreased with SIMV (2.46 +/- 0.40 vs. 4.07 +/- 0.38%, p < 0.01), which was confirmed by a decrease in renal collagen I and fibronectin expression. Serum cholesterol level did not change with SIMV. CONCLUSION: SIMV attenuated interstitial fibrosis associated with this model of hypertensive renal disease. The mechanism involved MCP-1 downregulation. SIMV treatment was also associated with a p21 downregulation in the kidney, which might be involved in the protection of renal scarring.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Hipertensão Renal/tratamento farmacológico , Hipertensão Renal/patologia , Sinvastatina/farmacologia , Albuminúria/imunologia , Albuminúria/patologia , Animais , Divisão Celular , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Matriz Extracelular/fisiologia , Hipertensão Renal/imunologia , Linfócitos/metabolismo , Linfócitos/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , RNA Mensageiro/análise , Ratos , Ratos Wistar , Cloreto de Sódio/farmacologia , Fator de Crescimento Transformador beta/genética
5.
Neuropsychopharmacology ; 25(5): 642-50, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11682247

RESUMO

Approximately one third of schizophrenic patients treated with neuroleptic drugs experience unpleasant subjective responses, that are collectively known as neuroleptic dysphoria. Experimental research in animals indicates that drug induced dopaminergic blockade in mesolimbic circuits, especially the nucleus accumbens, leads to impaired pleasure responsivity and dysphoria. The present study tested this putative mechanism in drug-free schizophrenic patients (n = 12), through inducing dysphoric responses with alphamethyl paratyrosine (AMPT) and simultaneously quantifying their baseline striatal dopmine (D(2)) function with (123)IBZM-SPECT imaging. Results showed a wide variability in the occurrence and severity of dysphoric responses, clearly distinguishing a dysphoric group from non-dysphoric responders. Severity of dysphoric responses, measured by standardized rating scales, correlated inversely with changes in D(2) receptor binding ratios (r = +0.82, p <.01). These results support the notion that striatal dopaminergic activity is not uniformly elevated in all schizophrenic patients, and the sub-group of individuals with lower baseline dopamine function are at an increased risk for dysphoric responses during antipsychotic therapy with dopaminergic blocking drugs.


Assuntos
Dopamina/fisiologia , Inibidores Enzimáticos/farmacologia , Neostriado/metabolismo , Receptores de Dopamina D2/metabolismo , Esquizofrenia/metabolismo , Psicologia do Esquizofrênico , alfa-Metiltirosina/farmacologia , Adulto , Afeto/efeitos dos fármacos , Benzamidas , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Neostriado/diagnóstico por imagem , Neostriado/efeitos dos fármacos , Pirrolidinas , Compostos Radiofarmacêuticos , Receptores de Dopamina D2/efeitos dos fármacos , Esquizofrenia/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único
6.
J Nucl Med ; 17(11): 983-4, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-978260

RESUMO

A patient is described whose multinodular thyroid gland was found to have a primary papillary adenocarcinoma, a metastatic renal-cell carcinoma, and focal nodular hyperplasia. To our knowledge, this is the first case report of such an unusual combination. In a patient with known malignancy elsewhere, the possibility that a recent thyroid mass may be a metastasis should be considered.


Assuntos
Adenocarcinoma/diagnóstico , Bócio Nodular/diagnóstico , Neoplasias Renais/diagnóstico , Cintilografia , Neoplasias da Glândula Tireoide/diagnóstico , Adenocarcinoma/complicações , Adenocarcinoma Papilar/complicações , Adenocarcinoma Papilar/diagnóstico , Feminino , Bócio Nodular/complicações , Humanos , Neoplasias Renais/complicações , Pessoa de Meia-Idade , Metástase Neoplásica , Tecnécio , Neoplasias da Glândula Tireoide/complicações
7.
J Nucl Med ; 17(10): 902-3, 1976 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-966059

RESUMO

Spleen images in a patient with monoclonal gammopathy showed numerous areas of decreased radiocolloid accumulation. Microscopic examination revealed areas of coagulation necrosis with diffuse amyloid infiltration in the spleen. In this patient, amyloidosis is considered to have caused the infarct.


Assuntos
Amiloidose/diagnóstico , Infarto do Baço/diagnóstico , Amiloidose/complicações , Coloides , Feminino , Humanos , Pessoa de Meia-Idade , Infarto do Baço/etiologia , Enxofre , Tecnécio
8.
J Nucl Med ; 18(1): 26-8, 1977 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-830823

RESUMO

In a series of 25 patients with histologically proven mass lesions of the posterior fossa, computerized transaxial tomography (CTT) and radionuclide (RN) brain imaging detected 23 (92%) and 22 (88%) of the 25 tumors, respectively. In this small group of patients, the difference is not statistically significant. When the results of both techniques were combined, the detection rate was 100%, which emphasizes the complementary value of the two procedures. The two lesions not detected by CTT were metastatic carcinomas, and contrast enhancement was not employed. The three lesions not detected by RN imaging were cystic. The results may represent underestimates of the true sensitivity of both techniques since the use of contrast enhancement with CTT and of posterior flow studies and magnified static RN images of the posterior fossa would probably improve the sensitivity of both tests.


Assuntos
Cintilografia , Neoplasias Cranianas/diagnóstico , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Fossa Craniana Posterior , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Cranianas/diagnóstico por imagem , Tecnécio
9.
J Nucl Med ; 16(4): 326-7, 1975 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1113191

RESUMO

In a 44-year-old woman, a pancreatic pseudocyst was demonstrated on delayed images obtained up to 8 days after the intravenous administration of 0.250 mCi 75Se-selenomethionine. The initial routine pancreas image study failed to visualize both the pancreas and the pancreatic pseudocyst. The diagnosis was confirmed at surgery and the fluid of the pancreatic pseudocyst contained 0.73% of the injected dose of the radioselenium.


Assuntos
Cisto Pancreático/diagnóstico , Cintilografia , Adulto , Feminino , Humanos , Metionina , Radioisótopos , Selênio , Fatores de Tempo
10.
J Nucl Med ; 17(11): 980-2, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-978259

RESUMO

Static brain images in a patient with subdural empyema showed findings similar to those of a subdural hematoma. The rapid-sequence study, however, showed increased peripheral activity on the affected side. Since this finding suggested an inflammatory process, further neuroradiologic evaluation and immediate surgical treatment were undertaken. The significance of the rapid-sequence study in subdural empyema has not been reported previously.


Assuntos
Abscesso Encefálico/diagnóstico , Meninges , Cintilografia , Espaço Subdural , Adulto , Humanos , Masculino , Infecções Estreptocócicas/diagnóstico , Tecnécio
11.
J Nucl Med ; 17(1): 61-4, 1976 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1244452

RESUMO

This paper considers abnormalities of flow patterns in the flow patterns in the cervical vasculature due to varying degrees of jugular venous reflux, and their influence on cerebral bloodflow studies. Two commonly encountered patterns are described. In the first group, the abnormal flow study resulted from reflux of the activity in the left internal jugular vein. In the second group, the observed abnormality resulted from reflux of the activity in the left internal jugular vein, followed by flow into the contralateral jugular vein, most probably through the transverse and sigmoid sinuses.


Assuntos
Transtornos Cerebrovasculares/diagnóstico , Veias Jugulares , Cintilografia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tecnécio
12.
J Nucl Med ; 35(12): 1959-64, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7989977

RESUMO

UNLABELLED: The myocardial perfusion agent, 99mTc-sestamibi (MIBI), offers the potential to combine renal and myocardial imaging because of high initial renal extraction and significant renal clearance. METHODS: Dynamic renal imaging was performed during rest MIBI injections in 3 normal subjects (NS) and 91 patients referred for cardiac assessment. Ten served as normal controls, and 81 were hypertensive. Renal activity of MIBI during the first transit, uptake and excretory phases of the study was quantified. These data were compared with the normal kinetics of 99mTc-diethylenetriaminepentaacetic acid (DTPA) in concurrent studies. RESULTS: With MIBI, clear definition of the kidneys was possible on all phases in most studies; occasionally, overlap with liver or spleen provided a minor problem. Renal MIBI activity reached levels 70% greater than DTPA during first transit and remained higher throughout the study; renal/background activity ratios were also higher on the MIBI study (p < 0.001). During the excretory phase with MIBI, hepatic and splenic activity did not decline, and gut activity increased. In NS, 40% of the total activity was excreted in the urine in 1 hr; urinary MIBI clearances approximated creatinine clearance. Asymmetry in initial renal uptake was seen in 14 of 81 hypertensive patients (17%); renal cysts and aortic dilatation could also be identified. CONCLUSION: These data suggest that ancillary renography during rest injection of MIBI could be a useful addition to the cardiovascular assessment of selected patients.


Assuntos
Hipertensão Renovascular/diagnóstico por imagem , Hipertensão/fisiopatologia , Rim/diagnóstico por imagem , Tecnécio Tc 99m Sestamibi , Meia-Vida , Humanos , Hipertensão/diagnóstico por imagem , Taxa de Depuração Metabólica , Valores de Referência , Pentetato de Tecnécio Tc 99m , Tecnécio Tc 99m Sestamibi/farmacocinética , Tomografia Computadorizada de Emissão
13.
J Nucl Med ; 31(4): 526-34, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2324830

RESUMO

NP-59 concentrates in steroid hormone synthesizing tissues, enabling scintigraphic localization and characterization of endocrine dysfunction in the adrenal cortex and ovary. Studying 108 consecutive cases from 1982 to 1985 and using clinical, biochemical, radiographic, and pathologic data, we performed a rigorous assessment of the accuracy and pitfalls of NP-59 scintigraphy. The evaluation was divided into categories of abnormal hormone secretion: Cushing's syndrome, primary aldosteronism, and hyperandrogenism. Additional categories included euadrenal tumors (without detectable hormone dysfunction) and sites of residual adrenal cortical tissue. The accuracy of NP-59 scintigraphy ranged from 71% in primary aldosteronism and 75% in euadrenal tumors, to 100% for Cushing's syndrome and hyperandrogenism. However, more than in most nuclear medicine studies, NP-59 imaging requires well-defined indications to be met for it to be efficacious, including the fulfillment of clear clinical, biochemical, and radiographic criteria. The high reproducibility of NP-59 scintigraphic interpretation was demonstrated when 40 random cases underwent interinstitutional exchange and through interobserver evaluation at the University of Michigan. Responses of 85/126 medical centers to questionnaires revealed the high level of NP-59 safety.


Assuntos
Adosterol , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Colesterol/análogos & derivados , Síndrome de Cushing/diagnóstico por imagem , Hiperaldosteronismo/diagnóstico por imagem , Radioisótopos do Iodo , Neoplasias Ovarianas/diagnóstico por imagem , Virilismo/diagnóstico por imagem , Adosterol/efeitos adversos , Glândulas Suprarrenais/diagnóstico por imagem , Feminino , Humanos , Cintilografia
14.
J Nucl Med ; 30(10): 1627-35, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2795203

RESUMO

We performed 38 cerebral perfusion studies in 33 patients with brain death or with severe central nervous system injury using technetium-99m hexamethyl-propyleneamine oxime [( 99mTc]HM-PAO). Uptake by the cerebrum and/or cerebellium was present in all patients who were not clinically brain dead (ten studies) although the study was often abnormal. In those patients who were brain dead, 16/17 studies demonstrated no uptake in either the cerebrum or cerebellum. In patients suspected of brain death, but who had conditions interfering with the diagnosis the test demonstrated no uptake in 9/11 studies, confirming brain death. A radionuclide angiogram (RNA) of the head was also performed in 33/38 studies and showed complete agreement with the [99mTc]HM-PAO uptake, except in one case. We conclude that cerebral perfusion imaging with [99mTc]HM-PAO is a simple, noninvasive and reliable test to confirm brain death. By comparison with conventional technetium agents, [99mTc]HM-PAO is not dependent on the quality of the bolus injection, is easier to interpret and allows evaluation of posterior fossa blood flow.


Assuntos
Morte Encefálica/diagnóstico por imagem , Lesões Encefálicas/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Adolescente , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Criança , Pré-Escolar , Humanos , Lactente , Pessoa de Meia-Idade , Compostos de Organotecnécio , Oximas , Angiografia Cintilográfica , Fluxo Sanguíneo Regional , Estudos Retrospectivos , Tecnécio Tc 99m Exametazima
15.
J Nucl Med ; 39(2): 339-45, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9476947

RESUMO

UNLABELLED: On poststress images with 99mTc-sestamibi (MIBI), increased lung uptake of the radiotracer may reflect severe or multivessel coronary artery disease. METHODS: We measured pulmonary/myocardial ratios of MIBI at standardized times on immediate poststress acquisitions and on delayed tomographic acquisitions. In 1500 sequential patients referred for rest and stress myocardial tomography, ancillary planar images were obtained 4 min postinjection at peak stress with exercise, either alone (exercise, n = 674), or after intravenous dipyridamole (dipyridamole, n = 826). RESULTS: Based on 95% confidence limits in the angiographic normals, high values for immediate acquisitions were found in 17% of dipyridamole studies and 15% of exercise studies. High values for delayed acquisitions were found in 10% of dipyridamole studies and 9% of exercise studies. For both stress modes, increased values were related (p < 0.001) to ischemic perfusion defects for immediate images, to fixed defects for delayed images, and to ventricular dilation in both cases. By logistic regression analysis, body weight and history of infarction were also minor independent determinants (p < 0.01) of delayed acquisitions. In a subset of 250 cases with angiographic correlation (163 with dipyridamole; 87 with exercise), immediate lung uptake was highly correlated with ventricular dysfunction and with coronary stenoses (p < 0.0001). Relationships were similar to those in a historic control series imaged with 201TI. Values for delayed poststress images, and for corresponding rest images, showed strong relationships to ventricular dysfunction but not to stenosis severity. CONCLUSION: The relationships of immediate lung uptake to scintigraphic and angiographic disease patterns suggest its possible diagnostic use as an indicator of stress-induced ventricular decompensation.


Assuntos
Dipiridamol/farmacologia , Teste de Esforço , Pulmão/diagnóstico por imagem , Tecnécio Tc 99m Sestamibi , Cateterismo Cardíaco , Angiografia Coronária , Doença das Coronárias/diagnóstico , Doença das Coronárias/diagnóstico por imagem , Feminino , Coração/diagnóstico por imagem , Coração/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Radioisótopos de Tálio , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/diagnóstico por imagem
16.
Psychiatry Res ; 107(3): 173-7, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11566433

RESUMO

In a research study aimed at examining the alterations in dopaminergic function in schizophrenia, the authors identified a surreptitious case scenario which provided new insights into the subjective and neurochemical effects of cannabis. A 38-year-old drug-free schizophrenic patient took part in a single photon emission computerized tomographic (SPECT) study of the brain, and smoked cannabis secretively during a pause in the course of an imaging session. Cannabis had an immediate calming effect, followed by a worsening of psychotic symptoms a few hours later. A comparison of the two sets of images, obtained before and immediately after smoking cannabis, indicated a 20% decrease in the striatal dopamine D2 receptor binding ratio, suggestive of increased synaptic dopaminergic activity. This observation offers a plausible biological explanation for the psychotogenic effects of cannabis in vulnerable individuals, and also raises speculations about an interaction between cannabinoid and dopaminergic systems in the brain reward pathways.


Assuntos
Cannabis/efeitos dos fármacos , Corpo Estriado/diagnóstico por imagem , Dopamina/metabolismo , Psicoses Induzidas por Substâncias/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Humanos , Masculino
17.
Can J Cardiol ; 6(5): 198-204, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2383791

RESUMO

In hypertensive patients with target organ damage the search for possible etiologic factors may be particularly relevant. To evaluate renal symmetry, differential renal uptake of thallium-201 was quantified on renal images at 30 mins to 3 h after tracer injection in 112 hypertensive patients undergoing myocardial perfusion scintigraphy for chest pain. In some patients, renal angiographic status was known at the time of thallium-201 scintigraphy (n = 10), or disease was highly suspected (failed angioplasty, n = 6); the remainder (n = 96) were 'screened' for renovascular disease by renal thallium-201 imaging; 32 normotensive patients with no history of renal disease served as controls. Validation of thallium-201 renal imaging was obtained in a total of 17 hypertensive patients who had correlating contrast angiography, confirming eight cases of unilateral or asymmetric bilateral renovascular disease. Renography with technetium-99m DTPA was performed in 28 patients; differential renal function according to this modality correlated well with differential renal uptake of thallium-201 (r = 0.98). Of the screened hypertensives, eight had marked asymmetry of differential renal uptake and eight had possibly significant asymmetry. Renal thallium-201 imaging provided the first evidence of asymmetric renal perfusion in four cases subsequently confirmed by abdominal angiography. In addition, four post angioplasty cases had persistent or progressive asymmetry of renal perfusion disclosed by this technique. Thus, ancillary renal imaging with thallium-201 can be used to identify hypertensive patients who should be considered for renal angiographic evaluation.


Assuntos
Coração/diagnóstico por imagem , Hipertensão Renovascular/diagnóstico por imagem , Hipertensão/etiologia , Rim/diagnóstico por imagem , Humanos , Cintilografia , Radioisótopos de Tálio
18.
Nucl Med Commun ; 12(10): 885-99, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1792024

RESUMO

Renal uptake of 201Tl may have a role in screening for renal asymmetry in hypertensive patients (HP) who are referred for myocardial scintigraphy. The qualitative aspects of digitized planar images, and quantified differential renal uptake (DRU) of 201Tl were rated by comparing a simple technique (S) for outlining each kidney with an interpolative background subtracted technique (IB). These parameters were assessed in an initial series of patients by varying the length of acquisition (from 1 to 5 min), delay in acquisition (from 10 to 210 min after injection), and image preparation (nine-point smoothing). Six blinded observers rated the quality of coded images. Image quality was improved (P less than 0.01) by increasing the length of acquisition to at least 2 min, by smoothing of the images and by imaging within 2 h of 201Tl injection. Variability in quantification of DRU was suboptimal with acquisition for only 1 min and was more adversely affected with S than with IB. Clinical application of the quantitative technique was assessed in 180 HP and 32 normotensive controls. With IB, the normal range for DRU was slightly greater than for S. The two techniques were comparable in identifying abnormal cases and found 21 +/- 3% (S) and 19 +/- 3% (IB) of HP as lying outside the normal 99% confidence interval. Both quantitative techniques showed excellent agreement with renal angiography (n = 24). Furthermore, preliminary experience with surface markers and with 180 degrees tomography suggests the potential for simultaneous correction for renal depth. These data justify the use of adjunctive renal imaging during myocardial scintigraphy with 201Tl.


Assuntos
Coração/diagnóstico por imagem , Hipertensão/diagnóstico por imagem , Rim/diagnóstico por imagem , Radioisótopos de Tálio/farmacocinética , Humanos , Hipertensão/etiologia , Rim/metabolismo , Cintilografia
19.
Clin Nucl Med ; 15(2): 88-94, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2178846

RESUMO

The detection of renovascular disease (RVD) has particular relevance in hypertensive patients (HP) who have symptoms of target organ damage. To evaluate the possibility of RVD in HP undergoing myocardial perfusion scintigraphy for chest pain symptoms, posterior renal images were obtained at 1-3 hours after Tl-201 injection. Analog and computer images were obtained for 5 minutes in 45 HP; 12 patients with no history of hypertension or renal disease served as normal controls. For qualitative analysis, images were coded and read by three observers as to symmetry of renal uptake. Differential renal uptake of Tl-201 (DRU) was quantitated on computer images. In normal controls, uptake was agreed on as symmetric. In HP, 6 patients had marked asymmetry of DRU and 4 had possibly significant asymmetry; 2 had decreased uptake in both kidneys suggesting bilateral RVD or nephrosclerosis. Objective correlation with DRU was obtained in 10 HP who had contrast angiography, confirming 4 cases of unilateral RVD and 2 of bilateral RVD. Thirteen patients also had renography with Tc-99m DTPA; differential renal function by this modality correlated well with DRU of Tl-201 (r = 0.98). Thus, DRU of Tl-201 can be used as a supplement to myocardial scintigraphy to identify HP who require further evaluation and treatment of RVD.


Assuntos
Hipertensão Renovascular/diagnóstico por imagem , Rim/diagnóstico por imagem , Radioisótopos de Tálio , Adulto , Feminino , Coração/diagnóstico por imagem , Humanos , Hipertensão/complicações , Hipertensão Renovascular/complicações , Isquemia/diagnóstico por imagem , Rim/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Compostos de Organotecnécio , Ácido Pentético , Cintilografia , Fluxo Sanguíneo Regional , Pentetato de Tecnécio Tc 99m
20.
Clin Nucl Med ; 18(10): 829-36, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8242973

RESUMO

Three-phase Tc-99m MDP scans of 61 patients with asymptomatic upper extremities randomly mixed with 17 studies of patients previously diagnosed with reflex sympathetic dystrophy were blindly interpreted by three observers. Asymmetry in any of the phases was recorded and a final diagnostic impression made. Thirteen of 17 reflux sympathetic dystrophy studies were rated abnormal by at least two observers. Mild to striking asymmetry was occasionally seen in all three phases in asymptomatic upper extremities. Twenty of 61 asymptomatic patients (33%) were rated abnormal by at least one observer, and 5 of 61 studies (8%) were rated abnormal by all observers. Asymmetries in normal patients occurred more commonly in the earlier phases, while asymmetry in the delayed images was mild in all but one. Tightening the criteria to exclude mild asymmetry in delayed images resulted in unacceptably low sensitivity for reflex sympathetic dystrophy (29%). Interobserver variability was most prominent in the flow and immediate images. In the diagnosis of reflex sympathetic dystrophy a greater reliance should be placed on the delayed images, which in themselves have an overall sensitivity of 94%. It is important, however, to recognize that occasional mild and rare moderate asymmetries in even the delayed images of normal individuals result in an overall lower specificity of 77%.


Assuntos
Braço/diagnóstico por imagem , Distrofia Simpática Reflexa/diagnóstico por imagem , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Cintilografia , Valores de Referência , Método Simples-Cego , Medronato de Tecnécio Tc 99m
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA