Transcriptomic analysis of elderly women with low muscle mass: association with immune system pathway

Despite the well-established association of gene expression deregulation with low muscle mass (LMM), the associated biological mechanisms remain unclear. Transcriptomic studies are capable to identify key mediators in complex diseases. We aimed to identify relevant mediators and biological mechanisms associated with age-related LMM. LMM-associated genes were detected by logistic regression using microarray data of 20 elderly women with LMM and 20 age and race-matched controls extracted from our SPAH Study (GSE152073). We performed weighted gene co-expression analysis (WGCNA) that correlated the identified gene modules with laboratorial characteristics. Gene enrichment analysis was performed and an LMM predictive model was constructed using Support Vector Machine (SVM). Overall, 821 discriminating transcripts clusters were identified (|beta coefficient| >1; p-value <0.01). From this list, 45 predictors of LMM were detected by SVM and validated with 0.7 of accuracy. Our results revealed that the well-described association of inflammation, immunity and metabolic alterations is also relevant at transcriptomic level. WGCNA highlighted a correlation of genes modules involved in immunity pathways with vitamin D level (R = 0.63, p = 0.004) and the Agatston score (R = 0.51, p = 0.02). Our study generated a predicted regulatory network and revealed significant metabolic pathways related to aging processes, showing key mediators that warrant further investigation.

[Evaluation of ischemic preconditioning on collateral circulation, ventricular function and clinical outcome in acute myocardial infarction]

PURPOSE

To evaluate the influence of ischemic preconditioning (IP) in collateral circulation (CC), early ventricular function and in hospital outcomes after myocardial infarction (MI).

METHODS

We studied 97 patients with a 1st anterior MI within 6h of pain and isolated total proximal occlusion of the left anterior descending artery, divided in 2 groups: with (GA) or without (GB) angina before MI. Coronariography and ventriculography were performed prior to reperfusion. The left ventricular (LV) ejection fraction was measured by the area length method and anterior wall motion by the centerline method.

RESULTS

There was no difference between the two groups in sex, age, CKMB level, treatment, reperfusion rate. Global LV ejection fraction and anterior wall motion were similar, respectively, 39 +/- 9% and -2.55 +/- 1.17 SD/chord for GA and 37 +/- 8% and -2.75 +/- 0.79 and -2.75 +/- 0.79 SD/chord for GB (p = ns). The incidence of visible CC to the infarct area was also similar (present in 6 GA vs 8 GB patients). However, GA patients fared significantly better during hospitalization: No GA patient presented Killip class > or = 2 compared to 8 GB patients (p = 0.007).

CONCLUSION

Although collateral coronary circulation grades, global and regional LV function were similar between the two groups, the presence of angina pectoris preceding an acute myocardial infarction was associated with a better in hospital evolution, what could be partially explained by preconditioning phoenomena.

[Magnetic resonance imaging in chronic Chagas cardiopathy. Correlation with endomyocardial biopsy findings]

PURPOSE

To study the correlation between magnetic resonance imaging of the heart and right ventricle endomyocardial biopsy results in chronic Chagas' heart disease.

METHODS

Ten patients with Chagas' disease, mean age 47 +/- 7 years, all males, in congestive heart failure with New York Heart Association class II (2 patients), III (6) and IV (2) were studied. Mean left ventricular ejection fraction was at echocardiogram 36 +/- 6%. The patients were submitted to right ventricular endomyocardial biopsy and magnetic resonance imaging of the heart. The results of this group were compared with a control group of patients with idiopathic dilated cardiomyopathy, with mean age of 46 +/- 10 years and left ventricular ejection fraction of 30 +/- 4%, in heart failure with functional class II (1 patient), III (5) and IV (1).

RESULTS

All patients with Chagas' heart disease presented an increase in magnetic ressonance imaging signal of the heart after gadolinium use. The septal signal intensity changed from 0.87 +/- 0.06 to 1.54 +/- 0.16 (p < 0.001). In the control group the mean septal signal intensity was 0.93 +/- 0.07 before and 0.89 +/- 0.06 after the gadolinium (p = ns). Eight patients of the Chagas' disease group had biopsy proven myocarditis and two had borderline myocarditis. However, only one patient of the control group had diagnosis of borderline myocarditis.

CONCLUSION

Myocarditis is frequently found in Chagas' heart disease patients and who unlike controls present a significant increase in myocardial signal intensity after gadolinium infusion. The magnetic resonance imaging of the heart seems a promising alternative method for the diagnosis of an inflammatory process in Chagas' heart disease.

[Aneurysms of the left and non coronary sinus of Valsalva associated to mitral and aortic rheumatic valves and obstructive coronary disease]

A 30 years old, male, patient with rare multiple aneurysms of sinus of Valsalva associated to mitral and aortic regurgitation and total occlusion of circumflex artery had the clinical diagnosis made accidentally. The multiple aneurysms were detected by transesophageal echodopplercardiography and hemodynamic study. The diagnosis were confirmed at surgery and the patient underwent correction of the aneurysms through the use of pericardial patches and mitral and aortic valve replacement.