Mind-body relationships in elite apnea divers during breath holding: a study of autonomic responses to acute hypoxemia

The mental control of ventilation with all associated phenomena, from relaxation to modulation of emotions, from cardiovascular to metabolic adaptations, constitutes a psychophysiological condition characterizing voluntary breath-holding (BH). BH induces several autonomic responses, involving both autonomic cardiovascular and cutaneous pathways, whose characterization is the main aim of this study. Electrocardiogram and skin conductance (SC) recordings were collected from 14 elite divers during three conditions: free breathing (FB), normoxic phase of BH (NPBH) and hypoxic phase of BH (HPBH). Thus, we compared a set of features describing signal dynamics between the three experimental conditions: from heart rate variability (HRV) features (in time and frequency-domains and by using nonlinear methods) to rate and shape of spontaneous SC responses (SCRs). The main result of the study rises by applying a Factor Analysis to the subset of features significantly changed in the two BH phases. Indeed, the Factor Analysis allowed to uncover the structure of latent factors which modeled the autonomic response: a factor describing the autonomic balance (AB), one the information increase rate (IIR), and a latter the central nervous system driver (CNSD). The BH did not disrupt the FB factorial structure, and only few features moved among factors. Factor Analysis indicates that during BH (1) only the SC described the emotional output, (2) the sympathetic tone on heart did not change, (3) the dynamics of interbeats intervals showed an increase of long-range correlation that anticipates the HPBH, followed by a drop to a random behavior. In conclusion, data show that the autonomic control on heart rate and SC are differentially modulated during BH, which could be related to a more pronounced effect on emotional control induced by the mental training to BH

A different immunologic profile characterizes patients with HER-2-overexpressing and HER-2-negative locally advanced breast cancer: implications for immune-based therapies

INTRODUCTION: The clinical efficacy of trastuzumab and taxanes is at least partly related to their ability to mediate or promote antitumor immune responses. On these grounds, a careful analysis of basal immune profile may be capital to dissect the heterogeneity of clinical responses to these drugs in patients with locally advanced breast cancer undergoing neoadjuvant chemotherapy. METHODS: Blood samples were collected from 61 locally advanced breast cancers (36 HER2- and 25 HER2+) at diagnosis and from 23 healthy women. Immunophenotypic profiling of circulating and intratumor immune cells, including regulatory T (Treg) cells, was assessed by flow cytometry and immunohistochemistry, respectively. Serum levels of 10 different cytokines were assessed by multiplex immunoassays. CD8+ T cell responses to multiple tumor-associated antigens (TAA) were evaluated by IFN-γ-enzyme-linked immunosorbent spot (ELISPOT). The Student's t test for two tailed distributions and the Wilcoxon two-sample test were used for the statistical analysis of the data. RESULTS: The proportion of circulating immune effectors was similar in HER2+ patients and healthy donors, whereas higher percentages of natural killer and Treg cells and a lower CD4+/CD8+ T cell ratio (with a prevalence of naïve and central memory CD8+ T cells) were observed in HER2- cases. Higher numbers of circulating CD8+ T cells specific for several HLA-A*0201-restricted TAA-derived peptides were observed in HER2+ cases, together with a higher prevalence of intratumor CD8+ T cells. Serum cytokine profile of HER2+ patients was similar to that of controls, whereas HER2- cases showed significantly lower cytokine amounts compared to healthy women (IL-2, IL-8, IL-6) and HER2+ cases (IL-2, IL-1β, IL-8, IL-6, IL-10). CONCLUSIONS: Compared to HER2- cases, patients with HER2-overexpressing locally advanced breast cancer show a more limited tumor-related immune suppression. This may account for the clinical benefit achieved in this subset of patients with the use of drugs acting through, but also promoting, immune-mediated effects

Cardiac dysfunction and hypothalamic activation during a social crowding stressor in prairie voles

Negative social interactions produce several detrimental consequences in humans and non-human animals; and conversely, positive social interactions may have stress-buffering effects on both behavior and physiology. However, the mechanisms underlying specific stressor-responsiveness in the context of the social environment are not well understood. The present study investigated the integration of behavior, cardiac function, and Fos-immunoreactivity in the hypothalamic paraventricular nucleus during an acute social stressor in female, socially monogamous prairie voles exposed to previous long-term pairing (control conditions) or isolation. Animals previously exposed to social isolation displayed increased heart rate, attenuated heart rate variability, and increased incidence of cardiac arrhythmias during an acute crowding stressor versus animals previously exposed to social pairing; these cardiac alterations were not secondary to behavioral changes during the crowding stressor. Furthermore, social isolation was associated with increased c-Fos-immunoreactivity in the hypothalamic paraventricular nucleus following the crowding stressor, versus social pairing. The prairie vole provides a useful model for understanding how the social environment contributes to changes in behavior, cardiac function, and central stress-regulatory processes in humans

Antioxidants in the Diet and Cognitive Function: Which Role for the Mediterranean Life-style?

This review aims to focus on main antioxidants- abundantly contained in the diet- as well as of the whole Mediterranean diet and life-style and their relationship with cognitive function, especially critical in two phases of life, in children until adolescence and oldness. The role of emerging biochemical and molecular biomarkers as opportunity to estimate more accurately nutritional assumption and requirement, in terms of cognitive preservation and disease risk, will be also discussed. The cluster of factors within the Mediterranean pattern -which include not only nutritional, but also physical, social, and stimulating aspects- is still largely understudied as a whole, but it is proposed as attractive research area and tool for public health planning of prevention and intervention

Pilot study on music-heart entrainment in a pianist during a live performance

Entrainment between music features and heart rhythms have been reported but, to date, evidence in support of music-heart synchronization are still inconsistent. We studied the possible music-heart entrainment in a skilled pianist during a live performance before an audience. We recorded ECG before and during the concert. We derived the beat-to-beat RR time series and analyzed heart rate variability in the time domain and with non linear analysis, to evaluate the autonomic changes associated with 4 different music pieces. Results indicated an autonomic modulation specific for each piece and the decrease and increase of parasympathetic and sympathetic tone across the whole session. Also, for each music piece, analysis of correlation between the music envelope and the RR series revealed a negative correlation which could be the expression of the entrainment of music on heart rhythm

The Effect of Aging on the Specialized Conducting System: A Telemetry ECG Study in Rats over a 6 Month Period

Advanced age alone appears to be a risk factor for increased susceptibility to cardiac arrhythmias. We previously observed in the aged rat heart that sinus rhythm ventricular activation is delayed and characterized by abnormal epicardial patterns although conduction velocity is normal. While these findings relate to an advanced stage of aging, it is not yet known when and how ventricular electrical impairment originates and which is the underlying substrate. To address these points, we performed continuous telemetry ECG recordings in freely moving rats over a six-month period to monitor ECG waveform changes, heart rate variability and the incidence of cardiac arrhythmias. At the end of the study, we performed in-vivo multiple lead epicardial recordings and histopathology of cardiac tissue. We found that the duration of ECG waves and intervals gradually increased and heart rate variability gradually decreased with age. Moreover, the incidence of cardiac arrhythmias gradually increased, with atrial arrhythmias exceeding ventricular arrhythmias. Epicardial multiple lead recordings confirmed abnormalities in ventricular activation patterns, likely attributable to distal conducting system dysfunctions. Microscopic analysis of aged heart specimens revealed multifocal connective tissue deposition and perinuclear myocytolysis in the atria. Our results demonstrate that aging gradually modifies the terminal part of the specialized cardiac conducting system, creating a substrate for increased arrhythmogenesis. These findings may open new therapeutic options in the management of cardiac arrhythmias in the elderly population

Respiratory pattern in awake rats: Effects of motor activity and of alerting stimuli

Our aim was to assess the impact of motor activity and of arousing stimuli on respiratory rate in the awake rats. The study was performed in male adult Sprague–Dawley (SD, n = 5) and Hooded Wistar (HW, n = 5) rats instrumented for ECG telemetry. Respiratory rate was recorded using whole-body plethysmograph, with a piezoelectric sensor attached for the simultaneous assessment of motor activity. All motor activity was found to be associated with an immediate increase in respiratory rate that remained elevated for the whole duration of movement; this was reflected by: i) bimodal distribution of respiratory intervals (modes for slow peak: 336 ± 19 and 532 ± 80 ms for HW and SD, p < 0.05; modes for fast peak 128 ± 6 and 132 ± 7 ms for HW and SD, NS); and ii) a tight correlation between total movement time and total time of tachypnoea, with an R2 ranging 0.96–0.99 (n = 10, p < 0001). The extent of motor-related tachypnoea was significantly correlated with the intensity of associated movement. Mild alerting stimuli produced stereotyped tachypnoeic responses, without affecting heart rate: tapping the chamber raised respiratory rate from 117 ± 7 to 430 ± 15 cpm; sudden side move — from 134 ± 13 to 487 ± 16 cpm, and turning on lights — from 136 ± 12 to 507 ± 14 cpm (n = 10; p < 0.01 for all; no inter-strain differences). We conclude that: i) sniffing is an integral part of the generalized arousal response and does not depend on the modality of sensory stimuli; ii) tachypnoea is a sensitive index of arousal; and iii) respiratory rate is tightly correlated with motor activity.Muammar M. Kabir, Mirza I. Beig, Mathias Baumert, Mimosa Trombini, Francesca Mastorci, Andrea Sgoifo, Frederick R. Walker, Trevor A. Day and Eugene Nalivaiko1. Introduction 2. Methods 2.1. Ethical approval and preliminary surgery 2.2. Recordings of respiration and gross motor activity 2.3. Experimental protocol 2.4. Data acquisition and analysis 3. Results 3.1. Respiration during basal conditions — qualitative observation 3.2. Assessment of respiratory indices and motor indices 3.3. Relationship between motor activity and respiratory pattern 3.4. Heart rate during basal conditions and its association with motor activity 3.5. Cardiac and respiratory responses to alerting stimuli 4. Discussion 4.1. Respiratory rate in spontaneously behaving rats 4.2. Dissociation between respiratory and cardiac responses to alerting stimuli 4.3. Neural mechanisms underlying motor-related and arousal-induced tachypnoea 4.4. Inter-strain differences 4.5. Physiological role of tachypnoeic responses 5. Conclusions Reference