Synchronization during an internally directed cognitive state in healthy aging and mild cognitive impairment: a MEG study

Mild cognitive impairment (MCI) is a stage between healthy aging and dementia. It is known that in this condition the connectivity patterns are altered in the resting state and during cognitive tasks, where an extra effort seems to be necessary to overcome cognitive decline. We aimed to determine the functional connectivity pattern required to deal with an internally directed cognitive state (IDICS) in healthy aging and MCI. This task differs from the most commonly employed ones in neurophysiology, since inhibition from external stimuli is needed, allowing the study of this control mechanism. To this end, magnetoencephalographic (MEG) signals were acquired from 32 healthy individuals and 38 MCI patients, both in resting state and while performing a subtraction task of two levels of difficulty. Functional connectivity was assessed with phase locking value (PLV) in five frequency bands. Compared to controls, MCIs showed higher PLV values in delta, theta, and gamma bands and an opposite pattern in alpha, beta, and gamma bands in resting state. These changes were associated with poorer neuropsychological performance. During the task, this group exhibited a hypersynchronization in delta, theta, beta, and gamma bands, which was also related to a lower cognitive performance, suggesting an abnormal functioning in this group. Contrary to controls, MCIs presented a lack of synchronization in the alpha band which may denote an inhibition deficit. Additionally, the magnitude of connectivity changes rose with the task difficulty in controls but not in MCIs, in line with the compensation-related utilization of neural circuits hypothesis (CRUNCH) model.     

Prognostic role of stress/rest myocardial perfusion scintigraphy in patients with cardiac syndrome x

Aim

The prognostic utility of myocardial perfusion scintigraphy (MPS) in patients with angiographically normal coronary arteries has not been evaluated yet. Our aim was to determine the prognostic role of positive MPS in patients with angina, positive exercise test and smooth coronary arteries (syndrome X).

Methods

A total of 156 patients with angina, positive exercise test, positive MPS and normal coronary arteries and 172 patients with angina and positive exercise test who had negative MPS were selected for study. The primary endpoint was combined all-cause mortality and hospitalizations for cardiac causes. The secondary endpoint was hospitalization for cardiac causes.

Results

Kaplan–Meier analysis showed a greater (p = 0.001) incidence of the primary endpoint in patients with positive MPS, compared to those with negative MPS. Additionally, Kaplan–Meier analysis for cardiovascular hospitalization showed a significant difference (p = 0.003) between the two groups. Cox regression analysis, adjusted for age, sex, BMI and antianginal therapy confirmed a significant risk increase for patients with positive MPS, with a hazard ratio (HR) = 3.20 (CI 95%: 1.14–9.02; p = 0.028). Cox analysis for cardiovascular hospitalization also showed a significant risk increase for patients with positive MPS (HR = 3.19; CI 95%: 1.13–9.00; p = 0.03). Finally, Cox analysis showed that patients with positive MPS tend to have a higher risk to remain symptomatic in the follow-up period (HR = 1.614; CI 95%: 0.999–2.607; p = 0.51).

Conclusions

This study shows that inducible myocardial hypoperfusion at MPS in patients with syndrome X could discriminate patients with a more severe prognosis, especially in terms of further hospitalization and symptomatic burden.     

Viabilidad de las muestras ganglionares obtenidas por ecobroncoscopia para el estudio de alteraciones epigenéticas en pacientes con cáncer de pulmón

Introduction

The diagnosis of microscopic lymph node metastasis in lung cancer is challenging despite the constant advances in tumor staging. The analysis of the methylation status of certain genes in lymph node samples could improve the diagnostic capability of conventional cyto-histological methods. The aim of this study was to demonstrate the feasibility of methylation studies using cytological lymph node samples.

Methods

Prospective study including 88 patients with a diagnosis or strong suspicion of non-small cell lung cancer, in which an echobronchoscopy was performed on mediastinal or hilar lymph nodes for diagnostic and/or staging. DNA was extracted from cytological lymph node samples and sodium bisulfite modification was performed. Methylation studies for p16/INK4a and SHOX2 were accomplished by MS-qPCR and pyrosequencing.

Results

The methodology used in our study yielded optimal/good DNA quality in 90% of the cases. No differences in DNA concentration were observed with respect to the lymph node biopsied and final diagnosis. Methylation analyses using MS-qPCR and pyrosequencing were not possible in a small number of samples mainly due to low DNA concentration, inadequate purity, fragmentation and/or degradation as a consequence of bisulfite conversion.

Conclusion

Methylation quantification using MS-qPCR and pyrosequencing of cytological lymph node samples obtained using echobronchoscopy is feasible if an appropriate DNA concentration is obtained, notably contributing to the identification of epigenetic biomarkers capable of improving decision-making for the benefit of potentially curable lung cancer patients.     

Temas de actualidad en cardiología: riesgo vascular y rehabilitación cardiaca

Cardiovascular disease develops in a slow and subclinical manner over decades, only to manifest suddenly and unexpectedly. The role of prevention is crucial, both before and after clinical appearance, and there is ample evidence of the effectiveness and usefulness of the early detection of at-risk individuals and lifestyle modifications or pharmacological approaches. However, these approaches require time, perseverance, and continuous development. The present article reviews the developments in 2013 in epidemiological aspects related to prevention, includes relevant contributions in areas such as diet, weight control methods (obesity is now considered a disease), and physical activity recommendations (with warnings about the risk of strenuous exercise), deals with habit-related psychosocial factors such as smoking, provides an update on emerging issues such as genetics, addresses the links between cardiovascular disease and other pathologies such as kidney disease, summarizes the contributions of new, updated guidelines (3 of which have recently been released on topics of considerable clinical importance: hypertension, diabetes mellitus, and chronic kidney disease), analyzes the pharmacological advances (largely mediocre except for promising lipid-related results), and finishes by outlining developments in the oft-neglected field of cardiac rehabilitation. This article provides a briefing on controversial issues, presents interesting and somewhat surprising developments, updates established knowledge with undoubted application in clinical practice, and sheds light on potential future contributions.     

Ejercicio físico y salud

Regular physical exercise is an established recommendation for preventing and treating the main modifiable cardiovascular risk factors, such as diabetes mellitus, hypertension, and dyslipidemia. Performing physical activity of moderate intensity for a minimum of 30 minutes 5 days a week or of high intensity for a minimum of 20 minutes 3 days a week improves functional capacity and is associated with reductions in the incidence of cardiovascular disease and mortality. Physical exercise induces physiological cardiovascular adaptations that improve physical performance, and only in extreme cases can these adaptations lead to an increased risk of physical exercise-associated complications. The incidence of sudden death or serious complications during physical exercise is very low and is concentrated in people with heart diseases or with pathological cardiac adaptation to exercise. Most of these cases can be detected by cardiology units or well-trained professionals.     

JAK2V617F monitoring in polycythemia vera and essential thrombocythemia: Clinical usefulness for predicting myelofibrotic transformation and thrombotic events

The JAK2V617F allele burden has been identified as a risk factor for vascular events and myelofibrotic transformation in polycythemia vera (PV) and essential thrombocythemia (ET). However, all previous studies have evaluated a single time point JAK2V617F measurement. Therefore, the frequency and the clinical significance of changes in the JAK2V617F mutant load occurring during the disease evolution remain unknown. In the present study, JAK2V617F monitoring was performed during the follow‐up of 347 patients (PV = 163, ET = 184). According to their JAK2V617F evolutionary patterns, patients were stratified as stable < 50% (n = 261), stable ≥50% (n = 52), progressive increase (n = 24) and unexplained decrease (n = 10). After a 2,453 person‐years follow‐up, a total of 59 thrombotic events, 16 major hemorrhages, and 27 cases of myelofibrotic transformations were registered. At multivariate analyses, patients with a persistently high (≥50%) or unsteady JAK2V617F load during follow‐up had an increased risk of myelofibrotic transformation (Incidence rate ratio [IRR]: 20.7, 95% CI: 6.5–65.4; P < 0.001) and a trend for a higher incidence of thrombosis (IRR: 1.7, 1–3.3; P = 0.05) than patients with a stable allele burden below 50%. In conclusion, JAK2V617F monitoring could be useful in patients with PV and ET for predicting disease's complications, especially myelofibrotic transformation. Am. J. Hematol. 89:517–523, 2014. © 2014 Wiley Periodicals, Inc.