No abstract

Myocardial infarction (MI) remains the leading cause of cardiovascular death worldwide and a major cause of heart failure. Recent studies have suggested that cell-based therapies with bone marrow stem cells (BMSC) and human amniotic membrane (hAM) would recover the ventricular function after MI; however, the mechanisms underlying these effects are still controversial. Herein, we aimed to compare the effects of BMSC and hAM in a rat model of heart failure. MI was induced through coronary occlusion, and animals with an ejection fraction (EF) < 50% were included and randomized into three groups: control, BMSC, and hAM. The BMSC and hAM groups were implanted on the anterior ventricular wall seven days after MI, and a new echocardiographic analysis was performed on the 30th day, followed by euthanasia. The echocardiographic results after 30 days showed significant improvements on EF and left-ventricular end-sistolic and end-diastolic volumes in both BMSC and hAM groups, without significant benefits in the control group. New blood vessels, desmine-positive cells and connexin-43 expression were also elevated in both BMSC and hAM groups. These results suggest a recovery of global cardiac function with the therapeutic use of both BMSC and hAM, associated with angiogenesis and cardiomyocyte regeneration after 30 days.

Acellular amniotic membrane (AM) has been studied, with promising results on the reconstruction of lesioned tissues, and has become an attractive approach for tracheal repair. This study aimed to evaluate the repair of the trachea with human umbilical cord mesenchymal stem cells (hucMSCs) differentiated in chondrocytes, grown on an experimental model. Tracheal defects were induced by surgical tracheostomy in 30 New Zealand rabbits, and the acellular amniotic membrane, with or without cells, was covering the defect. The hucMSCs were isolated and cultivated with chondrogenic differentiation over the culture of 14 days, and then grown on the AM. In this study, the AM was biocompatible and hucMSCs differentiated into chondrocytes. Our results demonstrated an important role for AM with cultured cells in the promotion of immature collagen, known to produce tissue regeneration. In addition, cartilaginous tissue was found at the tracheal defects, demonstrated by immunohistology results. This study suggests that this biomaterial implantation can be an effective future therapeutic alternative for patients with tracheal injury.

BACKGROUND The purpose of this study was to assess the utility of a handheld device (HH) used during common daily practice and its agreement with the results of a standard echocardiography study (STD) performed by experienced sonographers and echocardiographer. METHODS A prospective follow-up was conducted in an adult outpatient echocardiography clinic. Experienced sonographers performed the STD and an experienced echocardiographer performed the HH. STD included 2-dimensional images, Doppler and hemodynamics analysis. Hemodynamic assessment was not performed with the HH device because the HH does not include such technology. The images were interpreted by blinded echocardiographers, and the agreement between the reports was analyzed. RESULTS A total of 108 patients were included; and the concordance for left ventricle (LV) ejection fraction (EF), wall motion score index, LV and right ventricle (RV) function, RV size, and mitral and aortic stenosis was excellent with κ values greater than 0.80. Wall motion abnormalities had good concordance (κ value 0.78). The agreement for LV hypertrophy, mitral and aortic regurgitation was moderate, and tricuspid and pulmonary regurgitation agreements were low (κ values of 0.26 and 0.25, respectively). CONCLUSIONS In a daily practice scenario with experienced hands, HH demonstrated good correlation for most echocardiography indications, such as ventricular size and function assessment and stenosis valve lesion analyses.

No abstract