Dietary Polyphenols against Oxidative Stress in Head and Neck Cancer: What's New, What's Next.

Head and neck cancers (HNC) are a worldwide health problem, accounting for over 5% of all types of cancers. Their varied nature makes it sometimes difficult to find clear explanations for the molecular mechanisms that underline their onset and development. While chemio- and radiotherapy are clearly not to be dismissed, we cannot undervalue the effect that polyphenols - especially dietary polyphenols - can have in helping us to cope with this medical emergency. By influencing several different proteins involved in numerous different metabolic pathways, polyphenols can have a broad spectrum of biological action and can hopefully act synergistically to tackle down head and neck cancer. Moreover, being natural molecules, polyphenols does not present any side effects and can even enhance drugs efficacy, making our clinical therapy against head and neck cancer more and more effective. Certainly, oxidative stress plays an important role, altering several molecular pathways, lowering the body's defenses, and ultimately helping to create a microenvironment conducive to the appearance and development of the tumor. In this regard, the regular and constant intake of foods rich in polyphenols can help counteract the onset of oxidative stress, improving the health of the general population. In this review, we highlight the role of polyphenols in managing oxidative stress, with such positive effects that they can be considered new tools to use in our anti-head and neck cancer strategy.

Natural Bioactive Compounds against Oxidative Stress: Dietary Polyphenols Strike Back.

Oxidative stress is a major cellular and metabolic burden that can really alter cell life and become the base for disease onset and development. Many widespread pathologies can develop from an unresolved oxidative stress situation; thus, addressing this state is paramount for human health. Our antioxidant enzymes sometimes are not just enough. Fortifying our defense and the antioxidant and anti-inflammatory system can make a difference in our health: if this is attainable with our dietary habits, it could be a dream come true. Polyphenols are a fantastic tool indeed in the fight against oxidative stress: they are easy to obtain, with little cost, no side effects, and have a multitude of metabolic actions. This perspective review would shed light on polyphenol's metabolic and molecular action regarding oxidative stress to help preserve our health.

Safety threshold of R-wave amplitudes in patients with implantable cardioverter defibrillator.

OBJECTIVE: A safety threshold for baseline rhythm R-wave amplitudes during follow-up of implantable cardioverter defibrillators (ICD) has not been established. We aimed to analyse the amplitude distribution and undersensing rate during spontaneous episodes of ventricular fibrillation (VF), and define a safety amplitude threshold for baseline R-waves. METHODS: Data were obtained from an observational multicentre registry conducted at 48 centres in Spain. Baseline R-wave amplitudes and VF events were prospectively registered by remote monitoring. Signal processing algorithms were used to compare amplitudes of baseline R-waves with VF R-waves. All undersensed R-waves after the blanking period (120 ms) were manually marked. RESULTS: We studied 2507 patients from August 2011 to September 2014, which yielded 229 VF episodes (cycle length 189.6±29.1 ms) from 83 patients that were suitable for R-wave comparisons (follow-up 2.7±2.6 years). The majority (77.6%) of VF R-waves (n=13953) showed lower amplitudes than the reference baseline R-wave. The decrease in VF amplitude was progressively attenuated among subgroups of baseline R-wave amplitude (≥17; ≥12 to <17; ≥7 to <12; ≥2.2 to <7 mV) from the highest to the lowest: median deviations -51.2% to +22.4%, respectively (p=0.027). There were no significant differences in undersensing rates of VF R-waves among subgroups. Both the normalised histogram distribution and the undersensing risk function obtained from the ≥2.2 to <7 mV subgroup enabled the prediction that baseline R-wave amplitudes ≤2.5 mV (interquartile range: 2.3-2.8 mV) may lead to ≥25% of undersensed VF R-waves. CONCLUSIONS: Baseline R-wave amplitudes ≤2.5 mV during follow-up of patients with ICDs may lead to high risk of delayed detection of VF. TRIAL REGISTRATION NUMBER: NCT01561144; results.

Ablation of atrioventricular nodal reentrant tachycardia using remote magnetic guidance (stereotaxis) requires lower temperature and power settings because of improved local contact.

INTRODUCTION AND OBJECTIVES: The Stereotaxis(R) remote magnetic navigation system provides a new approach to ablation that could increase catheter stability. The aim was to determine whether improved tissue contact necessitates a change in traditional radiofrequency ablation parameters. METHODS: The study compared ablation of atrioventricular nodal reentrant tachycardia (AVNRT) using remote navigation (4-mm catheter) in 19 patients with conventional ablation in 18 patients (4-mm catheter, temperature 60-65 degrees C, power 50 W). The radiofrequency energy needed to ensure that no more than a single nodal echo beat could be induced was measured. RESULTS: Charring was observed with traditional parameters on the first applications of the remotely navigated catheter. Hence, the energy was subsequently reduced (to 50 degrees C and 40 W). There was no difference in the number of applications between remote navigation and conventional groups (median: 6 vs. 8.5; interquartile range [IQR]: 11 vs. 9). Applications lasting

Relationship between intraventricular cardiac asynchrony and degree of systolic dysfunction.

OBJECTIVES: Cardiac asynchrony is an area of study becoming more relevant in the evaluation and management of heart failure. Our aim was to determine the prevalence of cardiac asynchrony by Doppler echocardiography and to evaluate its relationship with the degree of left ventricular (LV) systolic dysfunction. METHODS: A total of 316 consecutive patients with LV ejection fraction less than 40% were enrolled. We divided them into 3 groups according to the degree of LV dysfunction: 31% to 40%, 21% to 30%, and less than 20%. Intraventricular asynchrony was evaluated using two methods: (1) measurement of the septal to posterior wall-motion delay (cut-off point 130 milliseconds); and (2) measurement of the difference between time from Q wave to LV ejection end, and the time from Q wave to the end of the systolic wave of the most delayed basal segment by Doppler tissue imaging (ejection- Doppler tissue imaging time; cut-off point 50 milliseconds). RESULTS: Mean age was 62.14 +/- 13.5 years (75.7% men). No differences were found among clinical electrical and echocardiographic variables among the groups. Furthermore, no relationship was found between the existence of intraventricular cardiac asynchrony and the degree of LV systolic dysfunction. These were similar in patients with ischemic dilated cardiomyopathy and nonischemic dilated cardiomyopathy. CONCLUSIONS: The degree of LV systolic dysfunction and its origin are not related to the presence of cardiac asynchrony. A specific echocardiographic Doppler study must always be performed to assess the existence of cardiac asynchrony in those who are candidates to resynchronization therapy.