排序方式: 共有22条查询结果,搜索用时 15 毫秒
1.
Tanja G. M. Vrijkotte Bert-Jan H. van den Born Christine M. C. A. Hoekstra Maaike G. J. Gademan Manon van Eijsden Susanne R. de Rooij Marcel T. B. Twickler 《PloS one》2015,10(9)
Background
In adults, increased sympathetic and decreased parasympathetic nervous system activity are associated with a less favorable metabolic profile. Whether this is already determined at early age is unknown. Therefore, we aimed to assess the association between autonomic nervous system activation and metabolic profile and its components in children at age of 5–6 years.Methods
Cross-sectional data from an apparently healthy population (within the ABCD study) were collected at age 5–6 years in 1540 children. Heart rate (HR), respiratory sinus arrhythmia (RSA; parasympathetic activity) and pre-ejection period (PEP; sympathetic activity) were assessed during rest. Metabolic components were waist-height ratio (WHtR), systolic blood pressure (SBP), fasting triglycerides, glucose and HDL-cholesterol. Individual components, as well as a cumulative metabolic score, were analyzed.Results
In analysis adjusted for child’s physical activity, sleep, anxiety score and other potential confounders, increased HR and decreased RSA were associated with higher WHtR (P< 0.01), higher SBP (p<0.001) and a higher cumulative metabolic score (HR: p < 0.001; RSA: p < 0.01). Lower PEP was only associated with higher SBP (p <0.05). Of all children, 5.6% had 3 or more (out of 5) adverse metabolic components; only higher HR was associated with this risk (per 10 bpm increase: OR = 1.56; p < 0.001).Conclusions
This study shows that decreased parasympathetic activity is associated with central adiposity and higher SBP, indicative of increased metabolic risk, already at age 5–6 years. 相似文献2.
Hedde van de Vooren Maaike G J Gademan Cees A Swenne Ben J TenVoorde Martin J Schalij Ernst E Van der Wall 《Journal of applied physiology》2007,102(4):1348-1356
The arterial baroreflex buffers slow (<0.05 Hz) blood pressure (BP) fluctuations, mainly by controlling peripheral resistance. Baroreflex sensitivity (BRS), an important characteristic of baroreflex control, is often noninvasively assessed by relating heart rate (HR) fluctuations to BP fluctuations; more specifically, spectral BRS assessment techniques focus on the BP-to-HR transfer function around 0.1 Hz. Skepticism about the relevance of BRS to characterize baroreflex-mediated BP buffering is based on two considerations: 1) baroreflex-modulated peripheral vasomotor function is not necessarily related to baroreflex-HR transfer; and 2) although BP fluctuations around 0.1 Hz (Mayer waves) might be related to baroreflex BP buffering, they are merely a not-intended side effect of a closed-loop control system. To further investigate the relationship between BRS and baroreflex-mediated BP buffering, we set up a computer model of baroreflex BP control to simulate normal subjects and heart failure patients. Output variables for various randomly chosen combinations of feedback gains in the baroreflex arms were BP resonance, BP-buffering capacity, and BRS. Our results show that BP buffering and BP resonance are related expressions of baroreflex BP control and depend strongly on the sympathetic gain to the peripheral resistance. BRS is almost uniquely determined by the vagal baroreflex gain to the sinus node. In conclusion, BP buffering and BRS are unrelated unless coupled gains in all baroreflex limbs are assumed. Hence, the clinical benefit of a high BRS is most likely to be attributed to vagal effects on the heart instead of to effective BP buffering. 相似文献
3.
M. G. J. Gademan A. van der Laarse C. A. Swenne E. E. van der Wall 《Netherlands heart journal》2009,17(6):224-225
Patients with chronic heart failure (CHF) have limited exercise capacity. Exercise intolerance in CHF is associated with increased mortality; 1 moreover, several studies suggest that interventions that increase exercise capacity in CHF improve prognosis. 2–4 Therefore, as Kemps and colleagues state in this issue of the Netherlands Heart Journal, 5 exercise testing is an important tool for evaluating and monitoring heart failure. 相似文献
4.
Background
The statistical modeling of biomedical corpora could yield integrated, coarse-to-fine views of biological phenomena that complement discoveries made from analysis of molecular sequence and profiling data. Here, the potential of such modeling is demonstrated by examining the 5,225 free-text items in the Caenorhabditis Genetic Center (CGC) Bibliography using techniques from statistical information retrieval. Items in the CGC biomedical text corpus were modeled using the Latent Dirichlet Allocation (LDA) model. LDA is a hierarchical Bayesian model which represents a document as a random mixture over latent topics; each topic is characterized by a distribution over words. 相似文献5.
J. L. I. Burggraaf T. W. Elffers F. M. Segeth F. M. C. Austie M. B. Plug M. G. J. Gademan A. C. Maan S. Man M. de Muynck T. Soekkha A. Simonsz E. E. van der Wall M. J. Schalij C. A. Swenne 《Netherlands heart journal》2013,21(4):183-188
Background
Exercise training is beneficial in health and disease. Part of the training effect materialises in the brainstem due to the exercise-associated somatosensory nerve traffic. Because active music making also involves somatosensory nerve traffic, we hypothesised that this will have training effects resembling those of physical exercise.Methods
We compared two groups of healthy, young subjects between 18 and 30 years: 25 music students (13/12 male/female, group M) and 28 controls (12/16 male/female, group C), peers, who were non-musicians. Measurement sessions to determine resting heart rate, resting blood pressure and baroreflex sensitivity (BRS) were held during morning hours.Results
Groups M and C did not differ significantly in age (21.4 ± 3.0 vs 21.2 ± 3.1 years), height (1.79 ± 0.11 vs 1.77 ± 0.10 m), weight (68.0 ± 9.1 vs 66.8 ± 10.4 kg), body mass index (21.2 ± 2.5 vs 21.3 ± 2.4 kg∙m−2) and physical exercise volume (39.3 ± 38.8 vs 36.6 ± 23.6 metabolic equivalent hours/week). Group M practised music daily for 1.8 ± 0.7 h. In group M heart rate (65.1 ± 10.6 vs 68.8 ± 8.3 beats/min, trend P =0.08), systolic blood pressure (114.2 ± 8.7 vs 120.3 ± 10.0 mmHg, P = 0.01), diastolic blood pressure (65.0 ± 6.1 vs 71.0 ± 6.2 mmHg, P < 0.01) and mean blood pressure (83.7 ± 6.4 vs 89.4 ± 7.1, P < 0.01) were lower than in group C. BRS in groups M and C was 12.9 ± 6.7 and 11.3 ± 5.8 ms/mmHg, respectively (P = 0.17).Conclusions
The results of our study suggest that active music making has training effects resembling those of physical exercise training. Our study opens a new perspective, in which active music making, additionally to being an artistic activity, renders concrete health benefits for the musician. 相似文献6.
Estimating the rate of evolution of the rate of molecular evolution 总被引:22,自引:13,他引:22
A simple model for the evolution of the rate of molecular evolution is
presented. With a Bayesian approach, this model can serve as the basis for
estimating dates of important evolutionary events even in the absence of
the assumption of constant rates among evolutionary lineages. The method
can be used in conjunction with any of the widely used models for
nucleotide substitution or amino acid replacement. It is illustrated by
analyzing a data set of rbcL protein sequences.
相似文献
7.
Vipond C Mulloy B Rigsby P Burkin K Bolgiano B;the MenC IS Working Group 《Biologicals》2012,40(5):353-363
Meningococcal group C (MenC) plain polysaccharide (PS) and conjugate vaccines are primarily evaluated by physicochemical methods to ensure that batches are consistently manufactured. As different assays are employed to quantify the MenC PS content of final formulations and bulk intermediaries, there is a need for an International MenC PS Standard to calibrate internal references used in the different laboratories. Twelve laboratories from nine different countries participated in a collaborative study to determine the MenC PS content of a candidate International Standard MenC PS preparation (08/214) and to assess its suitability. On the basis of the results from this study the candidate standard 08/214 was established as an International Standard for the quantification of MenC PS content in vaccines and components. It has a content of 1.192 ± 0.192 mg MenC PS/ampoule (expanded uncertainty with coverage factor of k = 2.365 corresponding to a 95% level of confidence), as determined by the resorcinol assays carried out by eight of the participating laboratories. The standard is available from The National Institute of Biological Standards and Control who act as guardians and distributors of the material under the auspices of WHO. 相似文献
8.
Background
Ensemble attribute profile clustering is a novel, text-based strategy for analyzing a user-defined list of genes and/or proteins. The strategy exploits annotation data present in gene-centered corpora and utilizes ideas from statistical information retrieval to discover and characterize properties shared by subsets of the list. The practical utility of this method is demonstrated by employing it in a retrospective study of two non-overlapping sets of genes defined by a published investigation as markers for normal human breast luminal epithelial cells and myoepithelial cells. 相似文献9.
Gademan MG van Bommel RJ Ypenburg C Haest JC Schalij MJ van der Wall EE Bax JJ Swenne CA 《American journal of physiology. Heart and circulatory physiology》2008,295(2):H755-H760
Metabolic and mechanical stress in the failing heart activates the cardiac sympathetic afferent reflex (CSAR). It has been demonstrated that cardiac resynchronization therapy (CRT) acutely reduces MSNA in clinical responders. Mechanistically, this beneficial effect might be explained by acute deactivation of the CSAR. In addition to sympathoexcitation, CSAR inhibits the arterial baroreflex at the level of the nucleus tractus solitarii. Hence, in responders, CRT is likely to remove/reduce this inhibition. Therefore, we hypothesized that CRT acutely facilitates the arterial baroreflex. One day after implantation of a CRT device in 32 patients with chronic heart failure (LVEF; 27 +/- 6%), we measured noninvasive baroreflex sensitivity (BRS) and heart rate variability (HRV) in two conditions: CRT device switched on and switched off (on/off order randomized). BRS changes were correlated with the difference in unpaced/paced LVEF, a measure of acute mechanical response to CRT. CRT increased BRS by 35% from 2.96 to 3.79 ms/mmHg (P < 0.02) and increased HRV (standard deviation of the intervals between normal beats) from 18.5 to 24.0 ms (P < 0.01). The CRT-induced relative change in BRS correlated with the change in LVEF (r = 0.44; P < 0.01). In conclusion, CRT acutely increases BRS and HRV. This favorable response of the autonomic nervous system might be caused by CRT-induced CSAR deactivation. Follow-up studies should verify the mechanism of the acute response and the possible predictive value of an acute positive BRS response. 相似文献
10.
Maaike G. J. Gademan Marloes Vermeulen Adri?tte J. J. M. Oostvogels Tessa J. Roseboom Tommy L. S. Visscher Manon van Eijsden Marcel T. B. Twickler Tanja G. M. Vrijkotte 《PloS one》2014,9(4)