RESUMO
We have evaluated cardiac function and fibrosis in infarcted male Wistar rats treated with MitoQ (50 mg/kg/day) or vehicle for 4 weeks. A cohort of patients admitted with a first episode of acute MI were also analyzed with cardiac magnetic resonance and T1 mapping during admission and at a 12-month follow-up. Infarcted animals presented cardiac hypertrophy and a reduction in the left ventricular ejection fraction (LVEF) and E- and A-waves (E/A) ratio when compared to controls. Myocardial infarction (MI) rats also showed cardiac fibrosis and endoplasmic reticulum (ER) stress activation. Binding immunoglobulin protein (BiP) levels, a marker of ER stress, were correlated with collagen I levels. MitoQ reduced oxidative stress and prevented all these changes without affecting the infarct size. The LVEF and E/A ratio in patients with MI were 57.6 ± 7.9% and 0.96 ± 0.34, respectively. No major changes in cardiac function, extracellular volume fraction (ECV), or LV mass were observed at follow-up. Interestingly, the myeloperoxidase (MPO) levels were associated with the ECV in basal conditions. BiP staining and collagen content were also higher in cardiac samples from autopsies of patients who had suffered an MI than in those who had died from other causes. These results show the interactions between mitochondrial oxidative stress and ER stress, which can result in the development of diffuse fibrosis in the context of MI.
RESUMO
Several classification systems have been described for stratifying patients with gastric carcinoma (GC). However, their prognostic value is low, and there is an urgent need for identification of molecular markers and development of new classifications. Retrospective study of 206 cases of GC diagnosed and surgically resected in our hospital between 2000 and 2017. Clinicopathological features of all cases were assessed and tissue microarrays were constructed for immunohistochemical (IHC) study. Patients were stratified based on IHC results. Mean patient age was 71 years and most patients were male (54.6%). Most tumors were located in the gastric antrum and body, and they were mostly fungoid or ulcerative lesions. GC were mainly intestinal-type tumors and 60.3% were diagnosed at pT3. 56.2% of patients showed recurrences and 29.4% died due to GC. According to our IHC classification, 23.5% of tumors showed microsatellite instability, 6% were E-cadherin negative, 53.5% were stable-p53 not overexpressed, and 17% were stable with p53 overexpression. IHC classification was significantly correlated with patient gender, gross morphology, Laurén classification, tumor necrosis, perineural infiltration, type of leading edge, and patient outcome. Multivariate analysis showed that IHC subtype was significantly and independently associated with overall survival, together with clinical symptoms, signet cell phenotype, tumor grade and vessel invasion. The application of IHC classifications based on molecular biomarkers in clinical practice can aid in the stratification of GC patients. More studies are needed to evaluate the reproducibility and clinical significance of these classifications.