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31.
Yayouk E. Willems Conor V. Dolan Catharina E. M. van Beijsterveldt Eveline L. de Zeeuw Dorret I. Boomsma Meike Bartels Catrin Finkenauer 《Behavior genetics》2018,48(2):135-146
This study used a theoretically-derived set of items of the Achenbach System of Empirically Based Assessment to develop the Achenbach Self-Control Scale (ASCS) for 7–16 year olds. Using a large dataset of over 20,000 children, who are enrolled in the Netherlands Twin Register, we demonstrated the psychometric properties of the ASCS for parent-, self- and teacher-report by examining internal and criterion validity, and inter-rater and test–retest reliability. We found associations between the ASCS and measures of well-being, educational achievement, and substance use. Next, we applied the classical twin design to estimate the genetic and environmental contributions to self-control. Genetic influences accounted for 64–75% of the variance in self-control based on parent- and teacher-report (age 7–12), and for 47–49% of the variance in self-control based on self-report (age 12–16), with the remaining variance accounted by non-shared environmental influences. In conclusion, we developed a validated and accessible self-control scale, and show that genetic influences explain a majority of the individual differences in self-control across youth aged 7–16 years. 相似文献
32.
Thom S. Lysen Hazel I. Zonneveld Ryan L. Muetzel M. Arfan Ikram Annemarie I. Luik Meike W. Vernooij Henning Tiemeier 《Journal of sleep research》2020,29(5)
Sleep problems increase with ageing. Increasing evidence suggests that sleep problems are not only a consequence of age‐related processes, but may independently contribute to developing vascular or neurodegenerative brain disease. Yet, it remains unclear what mechanisms underlie the impact sleep problems may have on brain health in the general middle‐aged and elderly population. Here, we studied sleep's relation to brain functioning in 621 participants (median age 62 years, 55% women) from the population‐based Rotterdam Study. We investigated cross‐sectional associations of polysomnographic and subjectively measured aspects of sleep with intrinsic neural activity measured with resting‐state functional magnetic resonance imaging on a different day. We investigated both functional connectivity between regions and brain activity (blood‐oxygen‐level‐dependent signal amplitude) within regions, hierarchically towards smaller topographical levels. We found that longer polysomnographic total sleep time is associated with lower blood‐oxygen‐level‐dependent signal amplitude in (pre)frontal regions. No objective or subjective sleep parameters were associated with functional connectivity between or within resting‐state networks. The findings may indicate a pathway through which sleep, in a ‘real‐life’ population setting, impacts brain activity or regional brain activity determines total sleep time. 相似文献
33.
Nils Krueger Stefanie Luebberding Mareike Oltmer Meike Streker Martina Kerscher 《Skin research and technology》2011,17(2):141-148
Background/purpose: The most commonly used method to determine the mechanical ability of skin is the creep test using suction chamber devices. Until now, there is no scientific consensus upon which skin deformation parameters and which body sites are particularly suitable to describe age‐related changes in human skin mechanics. The aim of this study was to find those mechanical skin parameters best representing influence of aging at five different body sites. Methods: A total of 120 healthy women aged 18–65, divided into four similar age groups, were included in this study. The biomechanical properties of the skin were measured using the Cutometer® MPA 580 on five body sites: cheek, neck, cleavage, volar forearm and back of the hand. In order to analyze parameters referred to 1 mm skin thickness, we also used 20 MHz sonography (DUB 20). Results: A high average correlation with age was found for the parameters Ua/Uf, Ur/Ue, Ur, Ur/Uf and Ua. Only low correlation with age was found for the parameters Uv/Ue, Uf‐Ua, Uf5/Uf, Ud/Uf and Ua5. The localizations cheek, forearm and neck showed the highest correlation with age, while cleavage showed only low correlation. Conclusion: According to the results of our study, we recommend the parameter ratio of elastic recovery to distensibility (Ur/Uf) as well as the gross elasticity (Ua/Uf) for evaluation of aging effects on the mechanical properties of skin. Their high correlation with age makes them particularly applicable to represent the influence of aging onto skin mechanical properties. Most suitable localizations to evaluate skin aging are cheek, forearm and neck. 相似文献
34.
35.
Dendritic cells, pro-inflammatory responses, and antigen presentation in a rodent malaria infection 总被引:15,自引:0,他引:15
Jean Langhorne ‡ Frank R. Albano Meike Hensmann Latifu Sanni † Emma Cadman Cecile Voisine Anne-Marit Sponaas 《Immunological reviews》2004,201(1):35-47
Summary: An infection of mice with Plasmodium chabaudi is characterized by a rapid and marked inflammatory response with a rapid but regulated production of interleukin‐12 (IL‐12), tumor necrosis factor‐α (TNF‐α), and interferon‐γ (IFN‐γ). Recent studies have shown that dendritic cells (DCs) are activated in vivo in the spleen, are able to process and present malaria antigens during infection, and may provide a source of cytokines that contribute to polarization of the CD4 T‐cell response. P. chabaudi‐infected erythrocytes are phagocytosed by DCs, and peptides of malaria proteins are presented on major histocompatibility complex (MHC) class II. The complex disulfide‐bonded structure of some malaria proteins can impede their processing in DCs, which may affect the magnitude of the CD4 T‐cell response and influence T‐helper 1 (Th1) or Th2 polarization. DCs exhibit a wide range of responses to parasite‐infected erythrocytes depending on their source, their maturational state, and the Plasmodium species or strain. P. chabaudi‐infected erythrocytes stimulate an increase in the expression of costimulatory molecules and MHC class II on mouse bone marrow‐derived DCs, and they are able to induce the production of pro‐inflammatory cytokines such as IL‐12, TNF‐α, and IL‐6, thus enhancing the Th1 response of naïve T cells. IFN‐γ and TNF‐α play a role in both protective immunity and the pathology of the infection, and the inflammatory disease may be regulated by IL‐10 and transforming growth factor‐β. It will therefore be important to elucidate the host and parasite molecules that are involved in activation or suppression of the DCs and to understand the interplay between these opposing forces on the host response in vivo during a malaria infection. 相似文献
36.
We aimed to investigate whether fear of suffocation predicts healthy persons' respiratory and affective responses to obstructed breathing as evoked by inspiratory resistive loads. Participants (N = 27 women, ages between 18 and 21 years) completed the Fear of Suffocation scale and underwent 16 trials in which an inspiratory resistive load of 15 cmH2O/l/s (small) or 40 cmH2O/l/s (large) was added to the breathing circuit for 40 s. Fear of suffocation was associated with higher arousal ratings for both loads. Loaded breathing was associated with a decrease in minute ventilation, but progressively less so for participants scoring higher on fear of suffocation when breathing against the large load. The present findings document a potentially panicogenic mechanism that may maintain and worsen respiratory discomfort in persons with fear of suffocation. 相似文献
37.
Hoekstra RA Bartels M Hudziak JJ Van Beijsterveldt TC Boomsma DI 《Behavior genetics》2008,38(5):447-461
We examined the contribution of genetic and environmental influences on the stability of withdrawn behavior (WB) in childhood
using a longitudinal multiple rater twin design. Maternal and paternal ratings on the withdrawn subscale of the Child Behavior
Checklist (CBCL) were obtained from 14,889 families when the twins were 3, 7, 10 and 12 years old. A longitudinal psychometric
model was fitted to the data and the fit of transmission and common factor models were evaluated for each variance component.
WB showed considerable stability throughout childhood, with correlation coefficients ranging from about .30 for the 9-year
time interval to .65 for shorter time intervals. Individual differences in WB as observed by the mother and the father were
found to be largely influenced by genetic effects at all four time points, in both boys (50–66%) and girls (38–64%). Shared
environmental influences explained a small to modest proportion (0–24%) of the variance at all ages and were slightly more
pronounced in girls. Non-shared environmental influences were of moderate importance to the variance and slightly increased
with age, from 22–28% at age 3 to 35–41% at age 12 years. The stability of WB was largely explained by genetic effects, accounting
for 74% of stability in boys and 65% in girls. Shared environmental effects explained 7% (boys) and 17% (girls) of the behavioral
stability. Most shared environmental effects were common to both raters, suggesting little influence of rater bias in the
assessment of WB. The shared environmental effects common to both raters were best described by a common factor model, indicating
that these effects are stable and persistent throughout childhood. Non-shared environmental effects accounted for the remaining
covariance over time.
Edited by Hermine Maes. 相似文献
38.
39.
Hoogendam YY van der Geest JN van der Lijn F van der Lugt A Niessen WJ Krestin GP Hofman A Vernooij MW Breteler MM Ikram MA 《Neurobiology of aging》2012,33(12):2774-2781
In a population-based study of 3962 community-dwelling nondemented elderly we investigated the relation of age, sex, cardiovascular risk factors, and the presence of infarcts with cerebellar volume, and its interrelationship with cerebral volumes. Cerebellar and cerebral gray and white matter were segmented using Freesurfer version 4.5 (http://surfer.nmr.mgh.harvard.edu/). We used linear regression analyses to model the relationship between age, sex, cardiovascular risk factors, brain infarcts, white matter lesions (WMLs) and cerebellar and cerebral volume. Smaller cerebellar volumes with increasing age were mainly driven by loss of white matter. Diabetes, higher serum glucose and lower cholesterol levels were related to smaller cerebellar volume. No association was found between hypertension, smoking, apolipoprotein E (ApoE) genotype, and cerebellar volume. Supratentorial lacunar infarcts and WMLs were related to smaller cerebellar volume. Infratentorial infarcts were related to smaller cerebellar white matter volume and total cerebral volume. This study suggests that determinants of cerebellar volume do not entirely overlap with those established for cerebral volume. Furthermore, presence of infarcts or WMLs in the cerebrum can affect cerebellar volume. 相似文献
40.
Ruptures of the anterior cruciate ligament (ACL) are common knee injuries that do not heal, even with surgical repair. Our research is directed towards developing novel, biological approaches that enable suture repair of this ligament. One promising strategy involves the insertion of a collagen hydrogel between the severed ends of the ACL. Cells migrate from the damaged ligament into the hydrogel and produce repair tissue. Here we have investigated the potential for augmenting this process by the transfer of insulin like growth factor (IGF) 1 cDNA to the repair cells using an adenovirus vector. The goal is to achieve direct, in situ gene delivery by loading the hydrogel with vector prior to its insertion into the defect. In a step-wise approach towards evaluating this process, we confirmed that monolayers of ACL fibroblasts were efficiently transduced by adenovirus vectors and continued to express transgenes when subsequently incorporated into the hydrogel; indeed, transgene expression persisted longer within collagen gels than in monolayer culture. Transfer of IGF-1 cDNA increased the cellularity of the gels and led to the synthesis and deposition of increased amounts of types I and III collagen, elastin, tenascin, and vimentin. The cells remained viable, even when subjected to high viral loads. Similar results were obtained when collagen hydrogels were preloaded with adenovirus prior to insertion into an experimental ACL lesion in vitro. These data confirm the promise of using vector-laden hydrogels for the in situ delivery of genes to cells within damaged ligaments and suggest novel possibilities for the biological repair of the ACL. 相似文献