Trabalho Miocárdio: uma revisão sistemática do novo método de ecocardiografia e aplicações clínicas / Myocardial Work: a systematic review of novel echocardiography method and clinical applications

Fundamento: O trabalho miocárdico (MW) é uma nova modalidade de imagem que surgiu como uma forma potencial de avaliação da função ventricular esquerda (VE) em vários cenários clínicos. Ele calcula curvas de tensão de ecocardiografia de rastreamento de manchas (STE) com uma curva de pressão LV estimada utilizando curvas padrão de pressão arterial braquial de forma não invasiva. Objetivo: O objetivo desta pesquisa foi fornecer um resumo do conhecimento atual da MW não invasiva e suas aplicações clínicas, incluindo insuficiência cardíaca (IC), doença arterial coronariana (DAC), cardiomiopatia (CMP) e hipertensão (HTN). Além disso, são discutidas as limitações e recomendações da MW na prática clínica. Métodos: Pesquisamos no banco de dados online PubMed para nossa coleta de dados. Usamos as seguintes palavras-chave; (trabalho construtivo do miocárdio) OU (trabalho septal desperdiçado)) OU (trabalho miocárdico global)) OU (trabalho miocárdico)) OU (trabalho construtivo do miocárdio) OU (ecocardiografia nova). Revisamos ainda doze estudos com leitura de texto completo e incluídos nesta revisão sistemática. Resultados: Embora os índices de MW, particularmente GWI e GCW, tenham mostrado uma boa correlação com FE e parâmetros de deformação, a oportunidade de oferecer informações incrementais que não são afetadas pelas condições de carga tornou a aplicação de MW particularmente útil em uma variedade de configurações clínicas. Conclusão: Comparado ao FE e GLS, o MW é um teste promissor com maior sensibilidade e acurácia na identificação de indivíduos com doença cardiovascular. Os médicos também devem depender dos sintomas e dos achados do ECG até que uma extensa pesquisa multicêntrica validando essa estratégia seja feita para estabelecer o valor incremental da MW na avaliação ecocardiográfica diária. (AU)

Background: Myocardial work (MW) is a novel imaging modality that has emerged as a potential left ventricular (LV) function assessment in various clinical settings. MW calculates speckle-tracking echocardiography strain curves with an estimated LV pressure curve by non-invasively utilizing standard brachial blood pressure curves. Objective: This study aimed to provide a summary of current knowledge of non-invasive MW and its clinical applications, including in heart failure, coronary artery disease, cardiomyopathy, and hypertension. In addition, the limitations, and recommendations of MW in clinical practice are discussed. Methods: We searched the PubMed database using the following keywords: (myocardial constructive work) OR (wasted septal work) OR (global myocardial work) OR (myocardial work) OR (myocardial constructive work) OR (novel echocardiography). We further subjected 12 studies to full-text review and included them in this systematic review. Results: While MW indices, particularly global work index and global constructed work, have shown good correlations with ejection fraction (EF) and strain parameters, the opportunity of offering incremental information that is unaffected by loading conditions has made MW application particularly useful in a variety of clinical settings. Conclusion: Compared to EF and global longitudinal strain, MW is a promising test with higher sensitivity and accuracy for identifying individuals with cardiovascular disease. Clinicians should also evaluate symptoms and electrocardiographic findings until extensive multicenter studies validating this strategy are performed to establish the incremental value of MW in daily echocardiographic assessments.(AU)

Development of Novel Animal Model for Studying Scoliosis Using a Noninvasive Method and Its Validation through Gene-Expression Analysis

STUDY DESIGN: To induce scoliosis in young female Wistar rats using a noninvasive method and to validate this model. PURPOSE: To induce scoliosis in a rat model noninvasively by bracing and to study the corresponding gene-expression profile in the spine and different organs. OVERVIEW OF LITERATURE: Scoliosis involves abnormal lateral curvature of the spine, the causes of which remain unclear. In the literature, it is suggested that scoliosis is genetically heterogeneous, as there are multiple factors involved directly or indirectly in its pathogenesis. Clinical and experimental studies were conducted to understand the etiology of anatomical alterations in the spine and internal organs, as the findings could help clinicians to establish new treatment approaches. METHODS: Twelve female Wistar rats aged 21 days were chosen for this study. Customized braces and real-time polymerase chain reaction (RT-PCR) primers for rats were designed using Primer 3 software. Radiological analysis (X-rays), histopathological studies, SYBR green, and RT-PCR analysis were performed. RESULTS: The spines of six rats were braced in a deformed position, which resulted in a permanent structural deformity as confirmed by X-ray studies. The remaining rats were used as controls. Quantitative studies of the expression of various genes (osteocalcin, pleiotrophins, matrix metalloproteinase-2 [MMP2] and MMP9, TIMP, interleukins 1 and 6, tumor necrosis factor-α) showed their differential expression and significant upregulation (p < 0.05) in different organs of scoliotic rats in comparison to those in control rats. Histopathological findings showed tissue necrosis and fibrosis in the brain, retina, pancreas, kidney, liver, and disc of scoliotic rats. CONCLUSIONS: Bracing is a noninvasive method for inducing scoliosis in an animal model with 100% reliability and with corresponding changes in gene expression. Scoliosis does not just involve a spine deformity, but can be referred to as a systemic disease on the basis of the pathological changes observed in various internal organs.

Fecal cortisol metabolites as indicators of stress in crab-eating-fox (Cerdocyoun thous) in captivity / Metabolitos fecais de cortisol como indicadores de estresse em cachorro-do-mato (Cerdocyoun thous) em cativeiro

Blood samples collection is a common method in biological research using domestic animals. However, most blood sampling techniques are complicated and highly invasive and may therefore not be appropriate for wildlife animals in research concerning stress. Thus, a non-invasive method to measure steroid hormones is critically needed. The first goal of this study was to determine how glucocorticoids concentrations are impacted by translocation and reproductive activity in crab-eating-fox (Cerdocyoun thous) in captivity. The physiological relevance of fecal glucocorticoid metabolites was further validated by demonstrating: (1) The translocation of a male to a females enclosure resulted in a 3.5-fold increase compared to baseline concentrations, (2) changes in adrenocortical activity, as reflected in concentrations of fecal cortisol metabolites during reproduction, gestation and lactation in females foxes, indicating that social interactions resulted in large increases of fecal glucocorticoids metabolites during the reproductive season. From these findings we conclude that fecal samples can be used for the non-invasive assessment of adrenocortical status in crab-eating-fox...

Coleta de sangue é um método comumente utilizado na pesquisa com animais domésticos. Entretanto, a técnica de coleta de sangue torna-se complicada e altamente invasiva em animais selvagens devido ao estresse, tornando-a inapropriada para pesquisa. Dessa maneira, métodos não invasivos utilizados na mensuração de hormonios tornam-se necessários. O principal objetivo deste estudo foi determinar como as concentrações de glucocorticoides atuam durante a translocação e a atividade reprodutiva de cachorro-do-mato (Cerdocyoun thous) em cativeiro. A relevância fisiológica da análise de metabolitos fecais de glucocorticoides pôde ser validada pela demonstração de que: (1) A translocação de machos para o recinto de fêmeas resultou em um aumento de 3.5 vezes comparado a concentrações basais; (2) mudanças na atividade adrenocortical, como reflexo das concentrações de metabolitos de cortisol fecal durante a reprodução, gestação e lactação em femeas de cachorro-do-mato (Cerdocyoun thous), indicaram que interações sociais resultaram em aumento de glucocorticoides fecais durante a época reprodutiva. Com estas constatações podemos concluir que amostras fecais podem ser usadas para acesso não invasivo da atividade adrenocortical em cachorro-do-mato (Cerdocyoun thous)...

A novel noninvasive method to detect rejection after heart transplantation

Prompt and accurate detection of rejection prior to pathological changes after organ transplantation is vital for monitoring rejections. Although biopsy remains the current gold standard for rejection diagnosis, it is an invasive method and cannot be repeated daily. Thus, noninvasive monitoring methods are needed. In this study, by introducing an IL-2 neutralizing monoclonal antibody (IL-2 N-mAb) and immunosuppressants into the culture with the presence of specific stimulators and activated lymphocytes, an activated lymphocyte-specific assay (ALSA) system was established to detect the specific activated lymphocytes. This assay demonstrated that the suppression in the ALSA test was closely related to the existence of specific activated lymphocytes. The ALSA test was applied to 47 heart graft recipients and the proliferation of activated lymphocytes from all rejection recipients proven by endomyocardial biopsies was found to be inhibited by spleen cells from the corresponding donors, suggesting that this suppression could reflect the existence of activated lymphocytes against donor antigens, and thus the rejection of a heart graft. The sensitivity of the ALSA test in these 47 heart graft recipients was 100%; however, the specificity was only 37.5%. It was also demonstrated that IL-2 N-mAb was indispensible, and the proper culture time courses and concentrations of stimulators were essential for the ALSA test. This preliminary study with 47 grafts revealed that the ALSA test was a promising noninvasive tool, which could be used in vitro to assist with the diagnosis of rejection post-heart transplantation.

Evaluación del test diagnóstico índice número de plaquetas/diámetro mayor del bazo, como predictor de la presencia de várices esofágicas en cirrosis hepática / Evaenluation of the diagnostic test of index platelet counts / size sple, as a predictor of the presence of esophageal varices in cirrhosis

OBJETIVO: Evaluar el índice número de plaquetas/diámetro mayor del bazo (P/DMB) como un método diagnóstico no invasivo de la presencia de várices esofágicas (VE) en pacientes con cirrosis hepática.MATERIAL Y MÉTODOS: Estudio de Test Diagnósticos, análisis retrospectivo. Se recolectaron los datos de pacientes, con el diagnóstico de cirrosis hepática, en el Servicio de Gastroenterología del Hospital Nacional Daniel Alcides Carrión (HNDAC), entre Septiembre 2010 y Enero 2011 posteriormente se calculó la sensibilidad, especificidad, valor predictivo positivo y negativo, razón de probabilidades positiva y negativa; utilizando a la endoscopía digestiva alta como patrón de oro.RESULTADOS: Se evaluaron los datos de 47 pacientes, la edad promedio fue de 60,74 años; la etiología fue consumo de alcohol en el 25,5%, y no determinada en el 48,9% de pacientes. El 25% de pacientes no presentaron VE y 74,5% las presentaron. El índice P/DMB se comparó con la endoscopía, encontrándose una Sensibilidad de 40%, Especificidad de 75%, Valores predictivos positivo y negativo de 82% y 30% respectivamente; y razón de probabilidades positiva y negativa de 1,6 y 0,8 respectivamente. CONCLUSIONES: El índice P/DMB no es una prueba diagnóstica efectiva para el diagnóstico de la presencia de VE en la muestra estudiada.

AIM: To evaluate the platelet count/spleen diameter (PC/SD) ratio as a non invasive diagnostic test to predict esophageal varices (VE) in patients with cirrhosis. METHODS: Diagnostic test study, retrospective analysis. Data was collected from patients with diagnosis of liver cirrhosis at gastrointestinal unit of Hospital Nacional Daniel Alcides Carrión between September 2010 and January 2011. Using a PC/SD ratio with a cut off value of 909, sensitivity, specificity, Positive and negative predictive values, positive and negative likelihood ratios were calculate. RESULTS: There were 47 patients; mean age of 60,74; etiology: alcoholic (25,5%); undeterminated (48,9%). Twenty-five percent patients had varices and 74,5% had no varices. The PC/SD ratio had a sensitivity of 40%, specificity of 75%, PPV of 82%, NPV 30%, LR (+) of 1,6 and LR (-) of 0,8. CONCLUSIONS: The PC/SD ratio was not an effective diagnostic test for esophageal varices.