Myomir dysregulation and reactive oxygen species in aged human satellite cells

Satellite cells that reside on the myofibre surface are crucial for the muscle homeostasis and regeneration. Aging goes along with a less effective regeneration of skeletal muscle tissue mainly due to the decreased myogenic capability of satellite cells. This phenomenon impedes proper maintenance and contributes to the age-associated decline in muscle mass, known as sarcopenia. The myogenic potential impairment does not depend on a reduced myogenic cell number, but mainly on their difficulty to complete a differentiation program. The unbalanced production of reactive oxygen species in elderly people could be responsible for skeletal muscle impairments. microRNAs are conserved post-transcriptional regulators implicated in numerous biological processes including adult myogenesis. Here, we measure the ROS level and analyze myomiR (miR-1, miR-133b and miR-206) expression in human myogenic precursors obtained from Vastus lateralis of elderly and young subjects to provide the molecular signature responsible for the differentiation impairment of elderly activated satellite cells. publisher: Elsevier articletitle: Myomir dysregulation and reactive oxygen species in aged human satellite cells journaltitle: Biochemical and Biophysical Research Communications articlelink: http://dx.doi.org/10.1016/j.bbrc.2016.03.030 content_type: article copyright: Copyright © 2016 The Authors. Published by Elsevier Inc. ispartof: Biochemical and Biophysical Research Communications vol:473 issue:2 pages:462-70 ispartof: location:United States status: publishe

Iron deficiency from the standpoint of cardiac rehabilitation : Novel therapeutic opportunities

Anemia is one of the most frequent comorbidities found in patients with coronary artery disease and chronic heart failure (CHF) who are being followed in cardiac rehabilitation facilities. The more frequent type of anemia is that caused by iron deficiency (IDA, iron-deficiency anemia): this review summarizes the state of the art of this topic. First of all, the mechanisms of IDA will be analyzed. Subsequently, a description of the main conditions where IDA can unfavorably affect the clinical course, and of its more frequent complications, will be presented (percutaneous interventions, heart surgery, CHF). Special attention will be paid in the description of anemia in the setting of CHF. To this regard, in recent years a relevant amount of research has been carried out, to determine whether treating anemia (either by directly stimulating erythropoiesis or by correcting iron deficiency by oral or intravenous route) is of any clinical and prognostic relevance in patients with CHF. The results of this research will therefore be summarized and critically discussed. Finally, we will outline the n-commer promising role of cardiac rehabilitation facilities and of its network of experts in the diagnosis, prognostic stratification and treatment of anemia and iron deficiency. o

Determination of Baroreflex Sensitivity during the Modified Oxford Maneuver by Trigonometric Regressive Spectral Analysis

BACKGROUND: Differences in spontaneous and drug-induced baroreflex sensitivity (BRS) have been attributed to its different operating ranges. The current study attempted to compare BRS estimates during cardiovascular steady-state and pharmacologically stimulation using an innovative algorithm for dynamic determination of baroreflex gain. METHODOLOGY/PRINCIPAL FINDINGS: Forty-five volunteers underwent the modified Oxford maneuver in supine and 60° tilted position with blood pressure and heart rate being continuously recorded. Drug-induced BRS-estimates were calculated from data obtained by bolus injections of nitroprusside and phenylephrine. Spontaneous indices were derived from data obtained during rest (stationary) and under pharmacological stimulation (non-stationary) using the algorithm of trigonometric regressive spectral analysis (TRS). Spontaneous and drug-induced BRS values were significantly correlated and display directionally similar changes under different situations. Using the Bland-Altman method, systematic differences between spontaneous and drug-induced estimates were found and revealed that the discrepancy can be as large as the gain itself. Fixed bias was not evident with ordinary least products regression. The correlation and agreement between the estimates increased significantly when BRS was calculated by TRS in non-stationary mode during the drug injection period. TRS-BRS significantly increased during phenylephrine and decreased under nitroprusside. CONCLUSIONS/SIGNIFICANCE: The TRS analysis provides a reliable, non-invasive assessment of human BRS not only under static steady state conditions, but also during pharmacological perturbation of the cardiovascular system

Report of the High-Level Commission on Carbon Prices

The purpose of this Commission is to explore explicit carbon-pricing options and levels that would induce the change in behaviors— particularly in those driving the investments in infrastructure, technology, and equipment—needed to deliver on the temperature objective of the Paris Agreement, in a way that fosters economic growth and development, as expressed in the Sustainable Development Goals (SDGs). This report does not focus on the estimation and evaluation of the climate change impacts that would be avoided by reducing carbon emissions. While the Commission also covers other policies relevant and important to carbon-pricing design and delivery on the Paris agreement, its primary focus is on pricing. This report has been prepared based on the Commission’s assessment of the available evidence and literature as well as on its members’ judgment, developed through their extensive international policy experience. While the commissioners are in broad agreement on the overall thrust of the arguments presented in the report, they may not necessarily support every single assertion and conclusion

Trigonometric Regressive Spectral Analysis Reliably Maps Dynamic Changes in Baroreflex Sensitivity and Autonomic Tone: The Effect of Gender and Age

BACKGROUND: The assessment of baroreflex sensitivity (BRS) has emerged as prognostic tool in cardiology. Although available computer-assisted methods, measuring spontaneous fluctuations of heart rate and blood pressure in the time and frequency domain are easily applicable, they do not allow for quantification of BRS during cardiovascular adaption processes. This, however, seems an essential criterion for clinical application. We evaluated a novel algorithm based on trigonometric regression regarding its ability to map dynamic changes in BRS and autonomic tone during cardiovascular provocation in relation to gender and age. METHODOLOGY/PRINCIPAL FINDINGS: We continuously recorded systemic arterial pressure, electrocardiogram and respiration in 23 young subjects (25+/-2 years) and 22 middle-aged subjects (56+/-4 years) during cardiovascular autonomic testing (metronomic breathing, Valsalva manoeuvre, head-up tilt). Baroreflex- and spectral analysis was performed using the algorithm of trigonometric regressive spectral analysis. There was an age-related decline in spontaneous BRS and high frequency oscillations of RR intervals. Changes in autonomic tone evoked by cardiovascular provocation were observed as shifts in the ratio of low to high frequency oscillations of RR intervals and blood pressure. Respiration at 0.1 Hz elicited an increase in BRS while head-up tilt and Valsalva manoeuvre resulted in a downregulation of BRS. The extent of autonomic adaption was in general more pronounced in young individuals and declined stronger with age in women than in men. CONCLUSIONS/SIGNIFICANCE: The trigonometric regressive spectral analysis reliably maps age- and gender-related differences in baroreflex- and autonomic function and is able to describe adaption processes of baroreceptor circuit during cardiovascular stimulation. Hence, this novel algorithm may be a useful screening tool to detect abnormalities in cardiovascular adaption processes even when resting values appear to be normal

Walks4work: Rationale and study design to investigate walking at lunchtime in the workplace setting

Background: Following recruitment of a private sector company, an 8week lunchtime walking intervention was implemented to examine the effect of the intervention on modifiable cardiovascular disease risk factors, and further to see if walking environment had any further effect on the cardiovascular disease risk factors. Methods. For phase 1 of the study participants were divided into three groups, two lunchtime walking intervention groups to walk around either an urban or natural environment twice a week during their lunch break over an 8week period. The third group was a waiting-list control who would be invited to join the walking groups after phase 1. In phase 2 all participants were encouraged to walk during their lunch break on self-selecting routes. Health checks were completed at baseline, end of phase 1 and end of phase 2 in order to measure the impact of the intervention on cardiovascular disease risk. The primary outcome variables of heart rate and heart rate variability were measured to assess autonomic function associated with cardiovascular disease. Secondary outcome variables (Body mass index, blood pressure, fitness, autonomic response to a stressor) related to cardiovascular disease were also measured. The efficacy of the intervention in increasing physical activity was objectively monitored throughout the 8-weeks using an accelerometer device. Discussion. The results of this study will help in developing interventions with low researcher input with high participant output that may be implemented in the workplace. If effective, this study will highlight the contribution that natural environments can make in the reduction of modifiable cardiovascular disease risk factors within the workplace. © 2012 Brown et al.; licensee BioMed Central Ltd

Prevalence and Persistence of Breathing Disorders in Chronic Heart Failure Patients: Preliminary Results from Home Telemonitoring in the HHH Study

In this paper we present preliminary results of the European Community multicountry trial HHH (Home or Hospital in Heart Failure), which assessed the prevalence and persistence of nocturnal breathing disorders in mild-to-moderate CHF patients. All subjects (465) carried out a baseline respiratory recording in the hospital, followed by 12 recordings (one per month) at home. The latter were totally self-managed by the patients, and data were transmitted to the referring hospital through telephone lines. We found that 43 % of the patients had a periodic breathing pattern (PB, waxing and waning of ventilation with or without apneas) during the night lasting ≥ 1 hour, and the apnea-hypopnea index (AHI) was ≥ 5 events/hour in 51 % of them. During the 1-year follow-up, a PB ≥ 1 hour and an AHI ≥ 5 events/hour were persistent (i.e., occurred in> 50 % of the recordings) in 43 % and 52 % of the patients. These findings confirm the high prevalence of nocturnal breathing disorders in CHF patients and show that in a large proportion of patients they tend to persist over time. 1

Heart Rate Variability Characteristics in Sedentary Postmenopausal Women Following Six Months of Exercise Training: The DREW Study

Article on heart rate variability characteristics in sedentary postmenopausal women following six months of exercise training

Prevalence and persistence of breathing disorders in chronic heart failure patients: preliminary results from home telemonitoring in the HHH study

In this paper we present preliminary results of the European Community multicountry trial HHH (Home or Hospital in Heart Failure), which assessed the prevalence and persistence of nocturnal breathing disorders in mild-to-moderate CHF patients. All subjects (465) carried out a baseline respiratory recording in the hospital, followed by 12 recordings (one per month) at home. The latter were totally self-managed by the patients, and data were transmitted to the referring hospital through telephone lines. We found that 43% of the patients had a periodic breathing pattern (PB, waxing and waning of ventilation with or without apneas) during the night lasting ≥1 hour, and the apnea-hypopnea index (AHI) was ≥5 events/hour in 51% of them. During the 1-year follow-up, a PB ≥ 1 hour and an AHI ≥ 5 events/hour were persistent (i.e., occurred in > 50% of the recordings) in 43% and 52% of the patients. These findings confirm the high prevalence of nocturnal breathing disorders in CHF patients and show that in a large proportion of patients they tend to persist over time. © 2005 IEEE