RESUMO
We determined the accuracy of distensibility index of inferior vena cava (dIVC) for evaluation of fluid responsiveness in rats with acute respiratory distress syndrome (ARDS) and validated this index for use in rat models. In protocol 1, E. coli lipopolysaccharide was administered in Wistar rats (n=7). After 24h, animals were mechanically ventilated, and stroke volume (SV) and dIVC quantified after blood drainage and subsequent volume expansion (albumin 20%). A receiver operating characteristic (ROC) curve was plotted to determine the optimal dIVC cutoff. In protocol 2, rats (n=10) were divided into fluid-responders (SV increase >5%) and nonresponders (SV increase <5%). The dIVC cutoff obtained from protocol 1 was 25%. Fluid responders had a 2.5 relative risk of low dIVC (<25%). The sensitivity, specificity, positive predictive, and negative predictive values for dIVC were 74%, 62%, 59%, and 76%, respectively. In conclusion, a dIVC threshold <25% was associated with positive response after volume expansion and could be used to titrate fluids in endotoxin-induced ARDS.
Assuntos
Síndrome do Desconforto Respiratório/patologia , Síndrome do Desconforto Respiratório/fisiopatologia , Veia Cava Inferior/fisiopatologia , Animais , Pressão Sanguínea/fisiologia , Modelos Animais de Doenças , Lipopolissacarídeos/toxicidade , Curva ROC , Ratos , Ratos Wistar , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/diagnóstico por imagem , Ultrassonografia , Veia Cava Inferior/diagnóstico por imagemRESUMO
Experimental studies have reported that aerobic exercise after asthma induction reduces lung inflammation and remodeling. Nevertheless, no experimental study has analyzed whether regular/moderate aerobic training before the induction of allergic asthma may prevent these inflammatory and remodeling processes. For this purpose, BALB/c mice (n = 96) were assigned into non-trained and trained groups. Trained animals ran on a motorized treadmill at moderate intensity, 30 min/day, 3 times/week, for 8 weeks, and were further randomized into subgroups to undergo ovalbumin sensitization and challenge or receive saline using the same protocol. Aerobic training continued until the last challenge. Twenty-four hours after challenge, compared to non-trained animals, trained mice exhibited: (a) increased systolic output and left ventricular mass on echocardiography; (b) improved lung mechanics; (c) decreased smooth muscle actin expression and collagen fiber content in airways and lung parenchyma; (d) decreased transforming growth factor (TGF)-ß levels in bronchoalveolar lavage fluid (BALF) and blood; (e) increased interferon (IFN)-γ in BALF and interleukin (IL)-10 in blood; and (f) decreased IL-4 and IL-13 in BALF. In conclusion, regular/moderate aerobic training prior to allergic asthma induction reduced inflammation and remodeling, perhaps through increased IL-10 and IFN-γ in tandem with decreased Th2 cytokines.
Assuntos
Remodelação das Vias Aéreas , Asma/imunologia , Citocinas/imunologia , Pulmão/imunologia , Condicionamento Físico Animal , Animais , Asma/induzido quimicamente , Líquido da Lavagem Broncoalveolar/imunologia , Imuno-Histoquímica , Inflamação , Interferon gama/imunologia , Interleucina-10/imunologia , Interleucina-13/imunologia , Interleucina-4/imunologia , Pulmão/patologia , Pulmão/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Ovalbumina/efeitos adversos , Pneumonia/induzido quimicamente , Pneumonia/imunologia , Pneumonia/patologia , Fator de Crescimento Transformador beta/imunologiaRESUMO
Circulating antibodies in chagasic patients interact with myocardial beta adrenergic and muscarinic cholinergic receptors, triggering intracellular signals that alter cardiac function along the course of the disease. However, until now, experimental data in models of chronically infected chagasic mice linking the effects on myocardial beta adrenergic and muscarinic receptors to cardiopulmonary dysfunction is lacking. Thus, we studied C57BL/6 mice 8 months after intraperitoneal injection of 100 trypomastigote forms of the Colombian strain of T. cruzi. Uninfected mice, matched in age, were used as controls. Histopathological analyses (inflammation and fibrosis) and radio-ligand binding assays for estimation of muscarinic and adrenergic receptor density were performed in myocardium tissue samples. When compared to controls, infected mice had electrical conduction disturbances, diastolic dysfunction, lower O2 consumption and anaerobic threshold. In addition, hearts of chronic chagasic mice had intense inflammation and fibrosis, and decreased beta adrenergic and increased muscarinic receptor densities than normal controls. Our data suggest that chronic T. cruzi infection causes alterations in cardiac receptor density and fibrosis deposition which can be associated with cardiac conduction abnormalities, diastolic dysfunction and lower exercise capacity, associating for the first time all these functional and histopathological alterations in chagasic mice.
Assuntos
Cardiomiopatia Chagásica/fisiopatologia , Miocárdio/metabolismo , Receptor Muscarínico M2/metabolismo , Receptores Adrenérgicos beta 1/metabolismo , Animais , Cardiomiopatia Chagásica/parasitologia , Doença Crônica , Modelos Animais de Doenças , Regulação para Baixo , Ecocardiografia , Eletrocardiografia , Teste de Esforço , Feminino , Coração/parasitologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/patologia , Trypanosoma cruzi/patogenicidade , Regulação para CimaRESUMO
Only rarely do myxomas originate from the mitral valve. This is the report of a 49-year-old woman presenting with congestive heart failure. The diagnosis of an intracardiac tumor involving the anterior cuspid of the mitral valve was made by transesophageal echocardiography. The patient underwent surgery for tumor resection and plasty of the valve was made with reconstruction and preservation of the valve. The diagnosis of myxoma was confirmed by histology. This is the 23rd case of myxoma of the mitral valve reported in the literature.