3,622 research outputs found
Neuropsychiatric Aspects of Healthy Aging: an Epidemiological Approach
Ageing is becoming a significant global challenge which will require economic and social adjustments. Aging causes morphological changes in the brain associated with increased prevalence and incidence of neuropsychiatric diseases, mostly depression, Alzheimer’s Disease (AD) and Parkinson’s disease (PD). Neuropsychiatric diseases impair quality of life and pose a high economic burden to individuals and society. Thus, in order to better face these challenging diseases, it is of importance to understand factors that could contribute in their pathophysiology.
It is now widely accepted that there is a strong genetic component in the development of neurodegenerative diseases, whereas emerging evidence is indicating also epigenetic mechanisms such as DNA methylation and histone acetylation as key players in the development of AD and PD. Also, women due to longer lifespans and unique
Effects of mechanical ventilation at low lung volume on respiratory mechanics and nitric oxide exhalation in normal rabbits
Lung mechanics, exhaled NO (NOe), and TNF-(alpha) in serum and bronchoalveolar lavage fluid were assessed in eight closed and eight open chest, normal anesthetized rabbits undergoing prolonged (3-4 h) mechanical ventilation (MV) at low volume with physiological tidal volumes (10 ml/kg). Relative to initial MV on positive end-expiratory pressure (PEEP), MV at low volume increased lung quasi-static elastance (+267 and +281%), airway (+471 and +382%) and viscolelastic resistance (+480 and +294%), and decreased NOe (-42 and -25%) in closed and open chest rabbits, respectively. After restoration of PEEP, viscoelastic resistance returned to control, whereas airway resistance remained elevated (+120 and +31%) and NOe low (-25 and -20%) in both groups of rabbits. Elastance remained elevated (+23%) only in closed-chest animals, being associated with interstitial pulmonary edema, as reflected by increased lung wet-to-dry weight ratio with normal albumin concentration in bronchoalveolar lavage fluid. In contrast, in 16 additional closed- and open-chest rabbits, there were no changes of lung mechanics or NOe after prolonged MV on PEEP only. At the end of prolonged MV, TNF-(alpha) was practically undetectable in serum, whereas its concentration in bronchoalveolar lavage fluid was low and similar in animals subjected or not subjected to ventilation at low volume (62 vs. 43 pg/ml). These results indicate that mechanical injury of peripheral airways due to their cyclic opening and closing during ventilation at low volume results in changes in lung mechanics and reduction in NOe and that these alterations are not mediated by a proinflammatory process, since this is expressed by TNF-(alpha) levels
Exacerbations and lung function decline in COPD: New insights in current and ex-smokers
SummaryAimTo investigate whether there is a significant relationship between an increased frequency of exacerbations and the rate of forced expiratory volume in 1s (FEV1) decline in COPD patients.Methods–measurementsAbout 102 COPD patients (44 smokers, 58 ex-smokers) participated in a 3-year prospective study. Exacerbations were identified as worsening of patient's respiratory symptoms as recorded on diary cards. Spirometry was performed every 6 months. The effect of frequent exacerbations on lung function was investigated using random effects models.ResultsThe median (mean(95% CI)) annual exacerbation rate was 2.85 (3.1 (2.7–3.6)). Patients with an annual exacerbation rate over the median rate had significantly lower baseline post-bronchodilation FEV1(%pred), higher MRC dyspnoea score and chronic cough compared to patients who had an annual exacerbation rate less than the median. The average annual rate of FEV1(%pred), adjusted for smoking decline (ΔFEV1), was found significantly increased in frequent compared to infrequent exacerbators (P=0.017). The highest ΔFEV1 was observed in smokers frequent exacerbators and a significant interaction between exacerbation frequency and ΔFEV1 was also observed in ex-smokers.ConclusionsOur findings suggest that an increased frequency of exacerbations is significantly associated with FEV1 decline even in ex-smokers. Thus, smoking and frequent exacerbations may have both negative impact on lung function. Smoking cessation and prevention of exacerbations should be a major target in COPD
Anaerobiosis influences virulence properties of Pseudomonas aeruginosa cystic fibrosis isolates and the interaction with Staphylococcus aureus
The airways of individuals with cystic fibrosis (CF) are abundantly colonised by Staphylococcus aureus and Pseudomonas aeruginosa. Co-infecting hypoxic regions of static mucus within CF airways, together with decreases in pulmonary function, mucus plugging and oxygen consumption by host neutrophils gives rise to regions of anoxia. This study determined the impact of anaerobiosis upon S. aureus-P. aeruginosa interactions in planktonic co-culture and mixed species biofilms in vitro. Whilst anoxia reduced the ability for P. aeruginosa CF isolates to dominate over S. aureus, this occurred in an isolate dependent manner. Investigations into the underlying mechanisms suggest that the anti-staphylococcal compound facilitating P. aeruginosa dominance under normoxia and anoxia is greater than 3 kDa in size and is heat-stable. Not all interspecies interactions studied were antagonistic, as S. aureus exoproducts were shown to restore and enhance P. aeruginosa motility under normoxia and anoxia in an isolate dependent manner. Collectively, this study suggests changes in oxygen availability within regions of the CF lung is likely to influence interspecies interactions and in turn, potentially influence disease progression
Anthropometric and physical characteristics allow differentiation of young female volleyball players according to playing position and level of expertise
The aim of our study was to determine the differences in some anthropometric and physical performance variables of young Croatian female volleyball players (aged 13 to 15) in relation to playing position (i.e., independent variable) and performance level within each position (i.e., independent variable). Players were categorized according to playing position (i.e., role) as middle blockers (n=28), opposite hitters (n=41), passer-hitters (n=54), setters (n=30), and liberos (n=28). Within each position, players were divided into a more successful group and a less successful group according to team ranking in the latest regional championship and player quality within the team. Height and body mass, somatotype by the Heath-Carter method, and four tests of lower body power, speed, agility and upper body power (i.e., dependent variables) were assessed. Players in different positions differed significantly in height and all three somatotype components, but no significant differences were found in body mass, body mass index or measured physical performance variables. Players of different performance level differed significantly in both anthropometric and physical performance variables. Generally, middle blockers were taller, more ectomorphic, less mesomorphic and endomorphic, whereas liberos were shorter, less ectomorphic, more mesomorphic and endomorphic than players in other positions. More successful players in all positions had a lower body mass index, were less mesomorphic and endomorphic, and more ectomorphic than less successful players. Furthermore, more successful players showed better lower body power, speed, agility and upper body power. The results of this study can potentially provide coaches with useful indications about the use of somatotype selection and physical performance assessment for talent identification and development
Determinants and Predictors of Grief Severity and Persistence: The Rotterdam Study
Objective: We aimed to explore correlates and predictors of bereavement severity and persistence (triggered by “loss of a loved one”; referent group partner loss) in the Rotterdam cohort. Method: We used linear regression to examine factors associated with grief severity using a cross-sectional analysis and logistic regression to determine prospective associations. Results: Cross-sectionaly, females, child-lost, higher depressive symptoms, lower education, and difficulties in daily activities were independently associated with a higher bereavement severity. Prospectively (6 years; response rate 71%), the baseline value of the grief severity was the single predictor significantly associated with grief persistence. Discussion: Our results suggest that only grief severity is independently associated with grief persistence. Further studies are needed to confirm ou
Uphill walking at iso-efficiency speeds
Uphill walking gait has been extensively studied, but the optimal uphill speed able to enhance the metabolic demand without increasing fatigability has so far received little attention. Therefore, the aim of this study was to assess the metabolic/kinematic demand at constant speed (6 km\ub7h 121 G0 level, G2 2% uphill, G7 7% uphill) and at iso-efficiency speeds (G2IES 5.2 km\ub7h 121 2% uphill and G7IES 3.9 km\ub7h 121 7% uphill). For this aim, physically active women (n:24, Age 33.40 \ub1 4.97 years, BMI 21.62 \ub1 2.06 kg/m-2) after an 8-min warm-up were studied on a treadmill for 10\u2b9 for every walking condition with a 5\u2b9 rest in between. Average
heart rate (AVG-HR), rating of perceived exertion (RPE) and kinematic variables (stance time, swing time, stride length, stride cycle, stride-length variability, stride-cycle variability and internal work) were studied. Modif\ufeffications in stance time, stride length and stride cycle (p<0.005), and lower internal-work values (p<0.001) occurred in G7IES in comparison to the other conditions. Swing time was significantly modified only in G7IES compared to G0 and G7 (p<0.001 and p<0.005, respectively). Stride-length variability and stride-cycle variability were higher in G7IES compared to the other conditions (p<0.001). G7 induced the highest AVG-HR (p<0.005) and RPE (p<0.001) compared to the other conditions. This study demonstrates that by applying the equation for
uphill walking gait, it is possible to maintain a similar metabolic demand and RPE at iso-efficiency speeds during
uphill compared to level walking, inducing at the same time a modification of the kinematic parameters of walking gait performed at the same slope condition
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