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1.
Acta Ortop Mex ; 36(1): 58-63, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-36099575

RESUMO

INTRODUCTION: Scoliosis is a complex deformity that affects all three planes of the axis of the spine. The association between neuromuscular pathology and vertebral alignment was initially described in 1960. Neuromuscular pathology is progressive and results in postural abnormalities. Surgical goals in patients with neuromuscular deformity include anatomical correction for sedation and ambulation, as well as functional improvement. The gold standard of treatment is by posterior approach with transpedicular screws. The "hands-free" technique saves surgical time, decreases radiation by reducing the use of fluoroscopy. The advent of 3D printing technology allows precise study of the anatomical area and detail of the deformity in its three planes. This model can be sterilized for transoperative guidance. A 13-year-old female patient who develops thoracolumbar neuromuscular scoliosis secondary to spastic cerebral palsy (CP), with previous instrumentation T11-L3 of which he develops severe proximal curve. After the segmentation of the three-dimensional model, pedicle violation greater than 2 mm towards bilateral medullary canal was detected in the pedicles of L1 and L2 of previous instrumentation, pedicle dysplasia and the morphological characteristics of the pedicles were observed. Three-dimensional planning and the use of surgical guides represent a tool for surgical planning, especially in severe cases and with pedicle dysplasia. It helps as a surgical guide for the placement of hands-free transpedicular screws with possible reduction of radiation and anesthetic time.


INTRODUCCIÓN: La escoliosis es una deformidad compleja que afecta los tres planos del eje de la columna vertebral. La asociación entre patología neuromuscular y la alineación vertebral fue descrita inicialmente en 1960. La patología neuromuscular es progresiva y resulta en anormalidades posturales. Las metas quirúrgicas en pacientes con deformidad neuromuscular engloban la corrección anatómica para la sedestación y deambulación, así como mejoría funcional. El estándar de oro de tratamiento es por vía posterior con tornillos transpediculares. La técnica de "manos libres" ahorra tiempo quirúrgico, disminuye la radiación al reducir el uso de fluoroscopía. El advenimiento de la tecnología de impresión 3D permite estudio preciso del área anatómica y detalle de la deformidad en sus tres planos. Este modelo puede ser esterilizado para guía transoperatoria. Paciente femenino de 13 años de edad que desarrolla escoliosis neuromuscular toracolumbar secundario a parálisis cerebral infantil (PCI) espástica, con instrumentación previa T11-L3 de la cual desarrolla curva severa proximal. Finalizada la segmentación del modelo tridimensional se detectó violación pedicular mayor a 2 mm hacia canal medular bilateral en los pedículos de L1 y L2 de instrumentación previa, displasia pedicular y se observaron las características morfológicas de los pedículos. La planeación tridimensional y el uso de guías quirúrgicas representan una herramienta para la planeación quirúrgica, sobre todo en casos severos y con displasia pedicular. Ayuda como guía quirúrgica para la colocación de tornillos transpediculares a manos libres con posible reducción de radiación y tiempo anestésico.


Assuntos
Escoliose , Fusão Vertebral , Cirurgia Assistida por Computador , Adolescente , Feminino , Humanos , Masculino , Duração da Cirurgia , Impressão Tridimensional , Escoliose/cirurgia , Fusão Vertebral/métodos
2.
Acta Ortop Mex ; 35(2): 125-131, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-34731911

RESUMO

INTRODUCTION: There are different pathologies of the lumbar spine that condition a biomechanical and clinical instability for its treatment, various stabilization techniques have been carried out that try to preserve the movement and the transmission of load of the affected segment such as the interspinatus ligamentplasty with Dallos® fiber. OBJECTIVE: To show the biomechanical variations of functional segment of lumbar spine of pigs, before and after performing the discectomy and ligamentoplasty with Dallos® fiber. MATERIAL AND METHODS: The lumbar segment was mounted in a servo-hydraulic multiaxial simulator. Mobility ranges of flexion, extension, lateral flexion and axial rotations were simulated under three conditions: 1. Natural segment, 2. Discectomy segment, and 3. Disectomized segment plus ligamentoplasty with Dallos® fiber. The mobility ranges are made up to a torque of 7.5 N-m The data of the torques and mobility ranges was collected in the simulator program and the results of the biomechanical changes between the three conditions described were plotted. RESULTS: It was shown that lumbar biomechanics is affected after discectomy mainly in flexion and extension. In the left axial bending and rotation movements, an alteration of torque and mobility ranges was found. CONCLUSIONS: The ligamentoplasty recovers part of the stability lost after discectomy preserving part of the disc height without reaching to equalize the movements as in the natural segment. After discectomy the distribution of force suggests that residual instability with ligament plasty may represent facet overload.


INTRODUCCIÓN: Existen diferentes patologías de la columna lumbar que condicionan una inestabilidad biomecánica y clínica para su tratamiento, se han efectuado diversas técnicas de estabilización que tratan de preservar el movimiento y la transmisión de carga del segmento afecto como la ligamentoplastía interespinosa con fibra Dallos®. OBJETIVO: Mostrar las variaciones biomecánicas de segmento funcional de columna lumbar de porcino, antes y después de realizar la discetomía y ligamentoplastía con fibra Dallos®. MATERIAL Y MÉTODOS: El segmento lumbar se montó en un simulador multiaxial servo-hidráulico. Se simularon rangos de movilidad de flexión, extensión, flexiones laterales y rotaciones axiales en tres condiciones: 1) segmento natural; 2) segmento discectomizado; y 3) segmento disectomizado más ligamentoplastía con fibra Dallos®. Los rangos de movilidad se realizan hasta un torque de 7.5 N-m. La data de los torques y rangos de movilidad se recolectó en el programa del simulador y se graficaron los resultados de los cambios biomecánicos entre las tres condiciones descritas. RESULTADOS: Se demostró que la biomecánica lumbar es afectada después de la discectomía principalmente en la flexión y la extensión. En los movimientos de flexión y rotación axial izquierdas, se comprobó una alteración del torque y los rangos de movilidad. CONCLUSIONES: La ligamentoplastía recupera parte de la estabilidad perdida postdiscectomía, preservando parte de la altura discal sin llegar a igualar los movimientos como en el segmento natural. Posterior a la discectomía, la distribución de la fuerza sugiere que la inestabilidad residual con ligamento plastía puede representar sobrecarga facetaria.


Assuntos
Discotomia , Poliésteres , Animais , Fenômenos Biomecânicos , Vértebras Lombares/cirurgia , Amplitude de Movimento Articular , Suínos
3.
Nutr Metab Cardiovasc Dis ; 27(8): 731-738, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28739186

RESUMO

BACKGROUND AND AIM: Epicardial fat (EF) is increased in obesity and has important interactions with atrial and ventricular myocardium. Most of the evidence in this scenario can be confused by the presence of comorbidities such as hypertension, diabetes and dyslipidemia, which are very common in this population. The influence of EF on atrial remodeling and cardiac function demands further investigation on morbidly obese without these comorbidities. METHODS AND RESULTS: We prospectively recruited 20 metabolically healthy morbidly obese and 20 normo-weights controls. The maximum P-wave duration (PWD) was analyzed by 12-lead electrocardiogram. Left atrial diameter (LAD), left ventricular ejection fraction (LVEF) and EF thickness (EFT) were evaluated by two-dimensional echocardiography. The mean of maximum PWD and LAD were significantly larger in the obese group as compared to the control group: 109.55 ± 11.52 ms × 89.38 ± 11.19 ms and 36.12 ± 3.46 mm × 31.45 ± 2.64 mm, (p < 0.0001). The mean LVEF was lower in the obese group: 63.15 ± 4.25% × 66.17 ± 3.37% (p < 0.017). The mean EFT was higher in the obese group: 7.72 ± 1.60 mm × 3.10 ± 0.85 mm (p < 0.0001). A positive correlation was found between EFT and PWD (r = 0.70; p = 0.001) and LAD (r = 0.667; p = 0.001). An inverse correlation was found between EFT and LVEF (r = -0.523; p = 0.001). In a multiple multivariate regression analysis the EFT remains correlated with LAD and LVEF. CONCLUSIONS: In a select group of morbidly obese, the excess of EF had a significant impact on atrial remodeling and cardiac function.


Assuntos
Tecido Adiposo/fisiopatologia , Adiposidade , Arritmias Cardíacas/etiologia , Função do Átrio Esquerdo , Obesidade Metabolicamente Benigna/complicações , Obesidade Mórbida/complicações , Pericárdio/fisiopatologia , Disfunção Ventricular Esquerda/etiologia , Função Ventricular Esquerda , Tecido Adiposo/diagnóstico por imagem , Adulto , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Remodelamento Atrial , Estudos Transversais , Ecocardiografia , Eletrocardiografia , Feminino , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/fisiopatologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade Metabolicamente Benigna/diagnóstico , Obesidade Metabolicamente Benigna/fisiopatologia , Obesidade Mórbida/diagnóstico , Obesidade Mórbida/fisiopatologia , Pericárdio/diagnóstico por imagem , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco , Volume Sistólico , Sístole , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/fisiopatologia
4.
Scand J Rheumatol ; 45(3): 202-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26324785

RESUMO

OBJECTIVES: The main purpose of the study was to investigate left ventricular (LV) subclinical systolic and diastolic dysfunction in childhood-onset systemic lupus erythematosus (c-SLE) patients using two-dimensional speckle-tracking (2DST) echocardiography. We also interrogated possible correlations between impairment of myocardial deformation and the SLE Disease Activity Index 2000 (SLEDAI-2K), as well as the presence of traditional and disease-related cardiovascular risk factors (CRFs). METHOD: A total of 50 asymptomatic patients and 50 controls (age 14.74 vs. 14.82 years, p = 0.83) were evaluated by standard and 2DST echocardiography. RESULTS: Despite a normal ejection fraction (EF), there was reduction in all parameters of LV longitudinal and radial deformation in patients compared to controls: peak longitudinal systolic strain (PLSS) [-20.3 (-11 to -26) vs. -22 (-17.8 to -30.4)%, p < 0.0001], PLSS rate [-1.19 ± 0.21 vs. -1.3 ± 0.25 s(-1), p = 0.0005], longitudinal strain rate in early diastole [1.7 (0.99-2.95) vs. 2 (1.08-3.00) s(-1), p = 0.0034], peak radial systolic strain [33.09 ± 8.6 vs. 44.36 ± 8.72%, p < 0.0001], peak radial systolic strain rate [1.98 ± 0.53 vs. 2.49 ± 0.68 s(-1), p < 0.0001], and radial strain rate in early diastole [-2.31 ± 0.88 vs. -2.75 ± 0.97 s(-1), p = 0.02]. Peak circumferential systolic strain [-23.67 ± 3.46 vs. -24.6 ± 2.86%, p = 0.43] and circumferential strain in early diastole [0.37 ± 0.17 vs. 0.41 ± 0.15, p = 0.27] were similar between patients and controls, although peak circumferential systolic strain rate [-1.5 ± 0.3 vs. -1.6 ± 0.3 s(-1), p = 0.036] was reduced in c-SLE. Further analysis of patients revealed a negative correlation between LV PLSS and SLEDAI-2K (r = -0.52, p < 0.0001), and also between LV PLSS and the number of CRFs per patient (r = -0.32, p = 0.024). CONCLUSIONS: 2DST echocardiography has identified subclinical LV deformation impairment in c-SLE patients. Disease activity and cumulative exposure to CRFs contribute to myocardial compromise.


Assuntos
Doenças Assintomáticas , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Ecocardiografia , Feminino , Humanos , Lúpus Eritematoso Sistêmico/epidemiologia , Masculino , Fatores de Risco , Sístole , Disfunção Ventricular Esquerda/epidemiologia , Adulto Jovem
5.
Lupus ; 24(6): 613-20, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25492941

RESUMO

OBJECTIVE: The objective of this article is to evaluate right ventricle strain imaging by two-dimensional speckle-tracking (2DST) in childhood-onset systemic lupus erythematosus (c-SLE). METHODS: Thirty-five c-SLE patients with no signs or symptoms of heart failure and 33 healthy volunteers were evaluated by standard echocardiogram and 2DST. Conventional parameters included tricuspid annular plane systolic excursion (TAPSE), RV tissue-Doppler-derived Tei index and systolic pulmonary artery pressure. Global peak longitudinal systolic strain (PLSS) and strain rate (PLSSR) of RV were obtained by 2DST. Demographic/clinical features, SLEDAI-2K/SLICC/ACR-DI and treatment were also assessed. RESULTS: The median current age was similar in patients and controls (14.75 vs. 14.88 years, p = 0.62). RV PLSS was significantly reduced in c-SLE (-24.5 ± 5.09 vs. -27.62 ± 3.02%, p = 0.003). Similar findings were observed after excluding patients with pulmonary hypertension (-24.62 ± 4.87% vs. -27.62 ± 3.02%, p = 0.0041). RV PLSS was positively correlated with TAPSE (r = +0.49, p = 0.0027) and negatively correlated with Tei index (r = -0.34, p = 0.04) in c-SLE. RV PLSSR was not different comparing patients and controls (-0.65 s(-1 )± 0.47 vs. -1.87 ± 0.49 s(-1), p = 0.07). Further analysis of c-SLE patients revealed higher frequencies of neuropsychiatric manifestations (39% vs. 0%, p = 0.007) and antiphospholipid antibodies (55% vs. 18%, p = 0.035) in those with RV PLSS ≤ -23.7% vs >-23.7%. No differences were evidenced in demographic data, disease activity/damage or treatments (p > 0.05). CONCLUSIONS: The present study, using a new and more sensitive technique, revealed subclinical RV systolic dysfunction in c-SLE patients that may have future prognostic implications. The novel association of asymptomatic RV dysfunction with neuropsychiatric manifestations and antiphospholipid antibodies may suggest common physiopathological pathways.


Assuntos
Ecocardiografia Doppler/métodos , Ecocardiografia/métodos , Lúpus Eritematoso Sistêmico/fisiopatologia , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/fisiopatologia , Adolescente , Anticorpos Antifosfolipídeos/imunologia , Criança , Estudos Transversais , Feminino , Humanos , Hipertensão Pulmonar/fisiopatologia , Imunossupressores/administração & dosagem , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico por imagem , Vasculite Associada ao Lúpus do Sistema Nervoso Central/fisiopatologia , Masculino , Reprodutibilidade dos Testes , Sístole/fisiologia , Adulto Jovem
6.
Scand J Med Sci Sports ; 24 Suppl 1: 57-65, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24944132

RESUMO

We evaluated the effects of recreational football training combined with calorie-restricted diet (football + diet) vs calorie-restricted diet alone (diet) on aerobic fitness, lipid profile, and insulin resistance indicators in type 2 diabetes (T2D) patients. Forty-four T2D patients aged 48-68 years (27 females, 17 males) were randomly allocated to the football + diet group (FDG; n = 22) or to the diet group (DG; n = 22), of whom 19 FDG and 15 DG subjects completed the study. The football training was performed for 3 × 40 min/week for 12 weeks. Dual-energy X-ray absorptiometry scanning, treadmill testing, and fasting blood samplings were performed pre and post-intervention. After 12 weeks, maximal oxygen uptake (VO2max ) was elevated (P < 0.05) by 10 ± 4% in FDG but not in DG (-3 ± 4%, P < 0.05). After 12 weeks, reductions in blood triglycerides (0.4 ± 0.1 mmol/L), total cholesterol (0.6 ± 0.2 mmol/L), low-density lipoprotein, and very low-density lipoprotein levels were observed only in FDG. Fat mass decreased (P < 0.05) by 3.4 ± 0.4 kg in FDG and 3.7 ± 0.4 kg in DG. The lower (P < 0.05) glucagon and homeostatic model assessment of insulin resistance indicated an improvement in insulin sensitivity in FDG. In conclusion, football combined with restricted diet was effective in enhancing VO2max , reducing total cholesterol and triglycerides, and increasing insulin sensitivity, potentially providing better tools for the prevention of T2D complications than diet alone.


Assuntos
Colesterol/sangue , Diabetes Mellitus Tipo 2/terapia , Terapia por Exercício/métodos , Resistência à Insulina , Aptidão Física , Futebol/fisiologia , Triglicerídeos/sangue , Idoso , Biomarcadores/sangue , Glicemia/metabolismo , Brasil , Restrição Calórica , Terapia Combinada , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Resultado do Tratamento
7.
Int Angiol ; 23(2): 134-8, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15507890

RESUMO

AIM: The aim of this study was to determine the prevalence and risk factors for peripheral occlusive vascular disease (POVD) in subjects with diabetes mellitus (DM) in Brazil. METHODS: We evaluated 236 diabetic individuals, in spontaneous demand, representing 471 legs. POVD was assessed by the ankle brachial index (ABI). RESULTS: The mean age was 62.1 years (range 22-89 years), 52% were male, 93.2% type II DM and the mean time to diagnosis was 7.9 years (range 0-37 years). Sixty percent were hypertensives. In 61% at least one pulse was diminished or absent. The prevalence of ischemia was 18% (ABI<0.9) while 22% had an ABI compatible with high grade arterial calcification (ABI>1.3). Overall less than 1/3 of the cases had the vascular exam that could be considered normal. The ABI was lower in subjects with pulse deficit (p<0.001), and a normal pulse had a negative predictive value for ischemia of more than 90%. Subjects with normal pulses were younger and had a decreased diabetes duration (p<0.001 and p<0.05, respectively). An increase in the duration of the diabetes was associated with a progressive decrease in the ABI (p<0.01). Female gender and hypertension were associated with a reduced ABI (p<0.01 and p<0.05, respectively). CONCLUSION: There is a high prevalence of POVD in diabetic individuals. The disease is associated with hypertension and female gender and gets worse with increasing duration of the diabetes.


Assuntos
Arteriopatias Oclusivas/epidemiologia , Diabetes Mellitus Tipo 2/sangue , Angiopatias Diabéticas/epidemiologia , Assistência Ambulatorial , Brasil/epidemiologia , Diabetes Mellitus Tipo 1/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência
8.
Heart ; 90(9): 1020-4, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15310690

RESUMO

OBJECTIVE: To study the diagnostic contribution of repeated transthoracic (TTE) and transoesophageal echocardiography (TOE) among patients with suspected infective endocarditis. METHODS: 262 patients with 266 episodes of suspected infective endocarditis were referred for TTE and TOE over three years in a 423 bed university cardiology hospital. Patients were a mean (SD) of 47.6 (17.9) years old. 139 (52.3%) episodes occurred in men and 127 (47.7%) in women. The diagnostic information obtained from repeated TTE and TOE examinations was evaluated relative to the diagnosis of endocarditis. RESULTS: TTE examinations were repeated in 192 (72.2%) and TOE examinations were repeated in 49 (18.4%) of 266 episodes. A mean of 2.4 TTE and 1.2 TOE examinations were performed for each episode of suspected endocarditis. The second and third TTEs added diagnostic information in 34 (26.7%) and the second and third TOEs added diagnostic information in 25 (19.7%) of 127 episodes with definite endocarditis. After the third TTE or TOE no additional diagnostic information was obtained. CONCLUSIONS: The diagnostic contribution of repeated TTE or TOE for the diagnosis of endocarditis decreased as the number of repetitions increased. In this setting, the data do not substantiate more than three TTE or TOE examinations as an efficient strategy to increase the diagnostic yield for all but selected patients with suspected endocarditis.


Assuntos
Endocardite Bacteriana/diagnóstico por imagem , Adulto , Estudos de Coortes , Ecocardiografia/estatística & dados numéricos , Ecocardiografia Transesofagiana/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
9.
In Vitro Cell Dev Biol Anim ; 40(1-2): 8-13, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15180434

RESUMO

This article describes the culture of epithelial cells from anterior and posterior midgut regions of adult Dendroctonus valens. Culture conditions were established, and cell adherence was improved by means of a new technique that allowed the cells to grow between two glass coverslips. Cytoplasmic projections occur as anterior midgut cells grow to confluence; these projections were not observed in cells of the posterior midgut. The optimal culture medium for the maintenance of these epithelial cells was Roswell Park Memorial Institute 1640 medium at 25 degrees C. Cells in Grace's medium died in 24 h. Cultures did not require CO(2) atmosphere, but culture development was favored by the microaerophilic environment and the dark conditions in which the cells were grown, between the coverslips.


Assuntos
Técnicas de Cultura de Células/métodos , Besouros/citologia , Células Epiteliais , Animais , Extensões da Superfície Celular/metabolismo , Células Cultivadas , Meios de Cultura/química , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Trato Gastrointestinal/citologia
10.
J Vasc Access ; 5(1): 33-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-16596537

RESUMO

Angioaccess-induced ischemia is an infrequent but cumbersome problem, because both limb ischemia correction and access salvage should be undertaken during the same procedure. This paper reports two cases that we successfully managed with a bridge graft to a small distal artery after fistula ligation.

11.
Braz. j. med. biol. res ; 36(11): 1501-1509, Nov. 2003. ilus, graf
Artigo em Inglês | LILACS | ID: lil-348294

RESUMO

Differentiation between stunned and infarcted myocardium in the setting of acute ischemia is challenging. Real time myocardial contrast echocardiography allows the simultaneous assessment of myocardial perfusion and function. In the present study we evaluated infarcted and stunned myocardium in an experimental model using real time myocardial contrast echocardiography. Sixteen dogs underwent 180 min of coronary occlusion followed by reperfusion (infarct model) and seven other dogs were submitted to 20 min of coronary occlusion followed by reperfusion (stunned model). Wall motion abnormality and perfusional myocardial defect areas were measured by planimetry. Risk and infarct areas were determined by tissue staining. In the infarct model, the wall motion abnormality area during coronary occlusion (5.52 ± 1.14 cm²) was larger than the perfusional myocardial defect area (3.71 ± 1.45 cm²; P < 0.001). Reperfusion resulted in maintenance of wall motion abnormality (5.45 ± 1.41 cm²; P = 0.43 versus occlusion) and reduction of perfusional myocardial defect (1.51 ± 1.29 cm²; P = 0.004 versus occlusion). Infarct size determined by contrast echocardiography correlated with tissue staining (r = 0.71; P = 0.002). In the stunned model, the wall motion abnormality area was 5.49 ± 0.68 cm² during occlusion and remained 5.1 ± 0.63 cm² after reperfusion (P = 0.07). Perfusional defect area was 2.43 ± 0.79 cm² during occlusion and was reduced to 0.2 ± 0.53 cm² after reperfusion (P = 0.04). 2,3,5-Triphenyl tetrazolium chloride staining confirmed the absence of necrotic myocardium in all dogs in the stunned model. Real time myocardial contrast echocardiography is a noninvasive technique capable of distinguishing between stunned and infarcted myocardium after acute ischemia.


Assuntos
Animais , Cães , Ecocardiografia , Infarto do Miocárdio , Corantes , Meios de Contraste , Modelos Animais de Doenças , Estudo de Avaliação , Fluorocarbonos , Infarto do Miocárdio , Miocárdio Atordoado , Fatores de Risco
12.
Braz J Med Biol Res ; 36(11): 1501-9, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14576906

RESUMO

Differentiation between stunned and infarcted myocardium in the setting of acute ischemia is challenging. Real time myocardial contrast echocardiography allows the simultaneous assessment of myocardial perfusion and function. In the present study we evaluated infarcted and stunned myocardium in an experimental model using real time myocardial contrast echocardiography. Sixteen dogs underwent 180 min of coronary occlusion followed by reperfusion (infarct model) and seven other dogs were submitted to 20 min of coronary occlusion followed by reperfusion (stunned model). Wall motion abnormality and perfusional myocardial defect areas were measured by planimetry. Risk and infarct areas were determined by tissue staining. In the infarct model, the wall motion abnormality area during coronary occlusion (5.52 1.14 cm(2) ) was larger than the perfusional myocardial defect area (3.71 1.45 cm (2); P < 0.001). Reperfusion resulted in maintenance of wall motion abnormality (5.45 1.41 cm (2); P = 0.43 versus occlusion) and reduction of perfusional myocardial defect (1.51 1.29 cm (2); P = 0.004 versus occlusion). Infarct size determined by contrast echocardiography correlated with tissue staining (r = 0.71; P = 0.002). In the stunned model, the wall motion abnormality area was 5.49 0.68 cm (2) during occlusion and remained 5.1 0.63 cm (2) after reperfusion (P = 0.07). Perfusional defect area was 2.43 0.79 cm (2) during occlusion and was reduced to 0.2 0.53 cm(2) after reperfusion (P = 0.04). 2,3,5-Triphenyl tetrazolium chloride staining confirmed the absence of necrotic myocardium in all dogs in the stunned model. Real time myocardial contrast echocardiography is a noninvasive technique capable of distinguishing between stunned and infarcted myocardium after acute ischemia.


Assuntos
Infarto do Miocárdio/diagnóstico por imagem , Animais , Corantes , Meios de Contraste , Modelos Animais de Doenças , Cães , Ecocardiografia/métodos , Fluorocarbonos , Infarto do Miocárdio/patologia , Miocárdio Atordoado/diagnóstico por imagem , Miocárdio Atordoado/patologia , Fatores de Risco , Coloração e Rotulagem , Sais de Tetrazólio
13.
Tree Physiol ; 21(1): 19-26, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11260820

RESUMO

Tropical moist forests are notable for their richness in tree species. The presence of such a diverse tree flora presents potential problems for scaling up estimates of water use from individual trees to entire stands and for drawing generalizations about physiological regulation of water use in tropical trees. We measured sapwood area or sap flow, or both, in 27 co-occurring canopy species in a Panamanian forest to determine the extent to which relationships between tree size, sapwood area and sap flow were species-specific, or whether they were constrained by universal functional relationships between tree size, conducting xylem area, and water use. For the 24 species in which active xylem area was estimated over a range of size classes, diameter at breast height (DBH) accounted for 98% of the variation in sapwood area and 67% of the variation in sapwood depth when data for all species were combined. The DBH alone also accounted for > or = 90% of the variation in both maximum and total daily sap flux density in the outermost 2 cm of sapwood for all species taken together. Maximum sap flux density measured near the base of the tree occurred at about 1,400 h in the largest trees and 1,130 h in the smallest trees studied, and DBH accounted for 93% of the variation in the time of day at which maximum sap flow occurred. The shared relationship between tree size and time of maximum sap flow at the base of the tree suggests that a common relationship between diurnal stem water storage capacity and tree size existed. These results are consistent with a recent hypothesis that allometric scaling of plant vascular systems, and therefore water use, is universal.


Assuntos
Árvores/fisiologia , Panamá , Árvores/anatomia & histologia , Árvores/metabolismo , Clima Tropical , Água/metabolismo , Água/fisiologia
14.
Arq Bras Cardiol ; 75(2): 125-36, 2000 Aug.
Artigo em Inglês, Português | MEDLINE | ID: mdl-10983029

RESUMO

OBJECTIVE: To assess by Doppler echocardiography the structural and functional alterations of rat heart with surgical induced extensive myocardial infarction. METHODS: Five weeks after surgical ligature of the left coronary artery, 38 Wistar-EPM rats of both sexes, 10 of them with extensive infarction, undergone anatomical and functional evaluation by Doppler echocardiography and then euthanized for anatomopathological analysis. RESULTS: Echocardiography was 100% sensible and specific to anatomopathological confirmed extensive miocardial infarction. Extensive infarction lead to dilatation of left ventricle (diastolic diameter: 0.89 cm vs.0.64 cm; systolic: 0. 72 cm vs. 0.33 cm) and left atrium (0.55 cm vs. 0.33 cm); thinning of left ventricular anterior wall (systolic: 0.14 cm vs. 0.23 cm, diastolic: 0.11 cm vs. 0.14 cm); increased mitral E/ A wave relation (6.45 vs. 1.95). Signals of increased end diastolic ventricle pressure, B point in mitral valve tracing in 62.5% and signs of pulmonary hypertension straightening of pulmonary valve (90%) and notching of pulmonary systolic flow (60%) were observed in animals with extensive infarction. CONCLUSION: Doppler echocardiography has a high sensitivity and specificity for detection of chronic extensive infarction. Extensive infarction caused dilatation of left cardiac chambers and showed in Doppler signals of increased end diastolic left ventricular pressure and pulmonary artery pressure.


Assuntos
Ecocardiografia Doppler , Coração/anatomia & histologia , Coração/fisiologia , Infarto do Miocárdio/diagnóstico por imagem , Miocárdio/patologia , Doenças dos Animais , Animais , Feminino , Ventrículos do Coração/diagnóstico por imagem , Masculino , Infarto do Miocárdio/patologia , Tamanho do Órgão , Ratos , Ratos Wistar , Valores de Referência , Sensibilidade e Especificidade , Disfunção Ventricular Esquerda/diagnóstico por imagem
15.
Arq Bras Cardiol ; 75(2): 137-44, 2000 Aug.
Artigo em Inglês, Português | MEDLINE | ID: mdl-10983030

RESUMO

Multiple arterial anomalies characterized by tortuosity and rolling of the pulmonary arteries and aorta were diagnosed on echocardiography in an asymptomatic newborn infant with a phenotype suggesting Ehlers-Danlos syndrome. These changes were later confirmed on angiography, which also showed peripheral vascular abnormalities. The electrocardiogram showed a probable hemiblock of the left anterosuperior branch, and the chest x-ray showed an excavated pulmonary trunk with normal pulmonary flow.


Assuntos
Anormalidades Múltiplas/diagnóstico por imagem , Aorta Torácica/anormalidades , Síndrome de Ehlers-Danlos/diagnóstico por imagem , Artéria Pulmonar/anormalidades , Angiografia , Aorta Abdominal/anormalidades , Aorta Abdominal/diagnóstico por imagem , Aorta Torácica/diagnóstico por imagem , Seguimentos , Humanos , Recém-Nascido , Masculino , Artéria Pulmonar/diagnóstico por imagem , Ultrassonografia
16.
Arq Bras Cardiol ; 74(3): 243-52, 2000 Mar.
Artigo em Inglês, Português | MEDLINE | ID: mdl-10951827

RESUMO

We report here a case of coronary artery fistula in a neonate with clinical signs of heart failure. The electrocardiogram showed signs of left ventricular hypertrophy and diffuse alterations in ventricular repolarization. Chest X-ray showed an enlargement of the cardiac silhouette with an increase in pulmonary flow. After echocardiographic diagnosis and angiographic confirmation, closure of the fistulous trajectory was performed with a detachable balloon with an early and late successful outcome.


Assuntos
Fístula Artério-Arterial/complicações , Anomalias dos Vasos Coronários/complicações , Insuficiência Cardíaca/etiologia , Fístula Artério-Arterial/diagnóstico , Fístula Artério-Arterial/terapia , Cateterismo/métodos , Angiografia Coronária , Anomalias dos Vasos Coronários/diagnóstico , Anomalias dos Vasos Coronários/terapia , Ecocardiografia Doppler , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Humanos , Lactente , Masculino
17.
Arq Bras Cardiol ; 74(5): 447-52, 2000 May.
Artigo em Inglês, Português | MEDLINE | ID: mdl-10951836

RESUMO

A rare association of pulmonary atresia with an intact septum was diagnosed through echocardiography in a fetus 32 weeks of gestational age. The diagnosis was later confirmed by echocardiography of the newborn infant and further on autopsy. The aortic valve was bicuspid with a pressure gradient of 81 mmHg, and the right ventricle was hypoplastic, as were the pulmonary trunk and arteries, and the blood flow was totally dependent on the ductus arteriosus.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Septos Cardíacos/diagnóstico por imagem , Atresia Pulmonar/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/congênito , Evolução Fatal , Feminino , Septos Cardíacos/embriologia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Hipertrofia Ventricular Esquerda/congênito , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Recém-Nascido , Gravidez , Atresia Pulmonar/complicações
18.
J Rheumatol ; 27(4): 1082-6, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10782841

RESUMO

OBJECTIVE: To evaluate echocardiographic/Doppler findings in patients with rheumatic fever whether or not clinical manifestations of carditis were present, and the followup of these findings 24 months after the acute phase. METHODS: Twenty-two patients with rheumatic fever (13 boys, 9 girls, mean age 11.0 years) were evaluated at baseline (at diagnosis) and after 3 and 6 mo of disease. Eighteen patients were reevaluated 24 mo later. The assessment included physical and cardiac examination, electrocardiogram, chest radiography, and color ECHO/Doppler performed blindly by different investigators. The control group included 15 healthy children. RESULTS: We observed clinical carditis in 8 patients (36.4%): Group 1, all with ECHO abnormalities. We observed no clinical cardiac manifestations in 14 patients (Group 2), but 5 (35.7%) had positive ECHO/Doppler abnormalities that persisted at least 6 mo in followup assessments. Mitral and aortic were the most frequently involved valves. In Group 1 we observed normalization of the ECHO/Doppler in 3 patients, improvement in 2, no change in 2, and worsening in one. Twelve of 14 patients without clinical carditis were reevaluated, including the 5 patients with ECHO/Doppler abnormalities during the initial evaluations; normalization or improvement was observed in 2 patients, no change in 2, and worsening in one. We observed no ECHO/Doppler abnormalities in the control group. CONCLUSION: This blind prospective study suggests the existence of asymptomatic carditis in some patients with rheumatic fever and the role ECHO/Doppler investigation could play in diagnosis and followup.


Assuntos
Ecocardiografia , Miocardite/diagnóstico por imagem , Cardiopatia Reumática/diagnóstico por imagem , Adolescente , Criança , Eletrocardiografia , Feminino , Seguimentos , Humanos , Masculino , Estudos Prospectivos , Radiografia , Ultrassonografia Doppler
19.
J Am Soc Echocardiogr ; 12(10): 785-91, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10511646

RESUMO

Dobutamine-atropine stress echocardiography (DASE) is an established method and has been shown to be accurate for the detection of coronary artery disease. Still, there are few large clinical studies that analyze the safety of DASE in general or the safety of performing it on an ambulatory basis. Most studies use a target heart rate as the primary end point regardless of whether asymptomatic ischemia occurs. Such studies have shown a serious cardiac event rate of approximately 0.3%. We prospectively studied 4,033 consecutive patients on an ambulatory basis and in the hospital with the use of DASE from July 1991 to December 1998. All tests were performed by an experienced physician, and all clinical and DASE data were stored in a large database organized at the beginning of the study. Dobutamine was infused in scalar doses of 5, 10, 20, 30, and 40 microg/kg per minute in 3-minute stages. Development of a new wall motion abnormality, achievement of 85% of target heart, and end of the DASE infusion protocol were used as an end point. If 85% of the target heart rate was not achieved, atropine was infused up to 1 mg in the absence of myocardial ischemia, which was used in 1,280 studies. There were 3,645 diagnostic tests, and 388 (10%) were found to be nondiagnostic. This result was due to poor image quality in 115 (3%), end of protocol in negative-submaximal examinations in 124 (3%), and limiting side effects in 149 (4%). Thirty-seven percent of the tests showed positive results for myocardial ischemia. Major test-related cardiac complications occurred in 10 (0.25%) patients and included 1 ventricular fibrillation, 1 case of myocardial infarction, and 8 cases of sustained ventricular tachycardia. Atropine poisoning was observed in 5 (0.12%) patients. No deaths occurred as a direct or indirect consequence of DASE. We conclude that dobutamine-atropine stress echocardiography is a reasonably safe method for detection of coronary artery disease in the hospital or in an ambulatory basis. The use of new wall motion abnormality as 1 of the end points may prevent further ischemia-related complications.


Assuntos
Atropina , Cardiotônicos , Doença das Coronárias/diagnóstico por imagem , Dobutamina , Ecocardiografia/métodos , Parassimpatolíticos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Atropina/efeitos adversos , Cardiotônicos/efeitos adversos , Distribuição de Qui-Quadrado , Criança , Dobutamina/efeitos adversos , Eletrocardiografia , Teste de Esforço , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Parassimpatolíticos/efeitos adversos , Estudos Prospectivos , Estatísticas não Paramétricas
20.
Cell Immunol ; 194(1): 98-102, 1999 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-10357885

RESUMO

Considering that nitric oxide (NO) may be involved in anti-tumoral and anti-parasite lectin effects, in this report we investigated whether lectin induces NO production. Lectins from Canavalia brasiliensis, Dioclea grandiflora, Pisum arvense (PAA), and concanavalin A induced murine peritoneal cells to produce NO in vitro. PAA induced similar levels to that obtained with lipopolysaccharide plus interferon-gamma. NO production by adherent cells was significantly lower than that of unfractionated cells, suggesting a combination of lectin stimuli directly on macrophages and via lymphocyte stimulation. Ex vivo experiments showed that cells stimulated in vivo could maintain NO production in vitro without further stimuli. NO synthesis blockage in vivo can significantly increase cell numbers in draining lymph nodes after lectin injection compared to unblocked controls, suggesting an in vivo association of lectin stimuli and NO production. Taken together these data show that lectins can induce NO production both in vitro and in vivo.


Assuntos
Lectinas/imunologia , Óxido Nítrico/biossíntese , Lectinas de Plantas , Animais , Células Cultivadas , Concanavalina A/imunologia , Concanavalina A/farmacologia , Feminino , Lectinas/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Peritônio/citologia
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