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141.
Loens K Ieven M Pattyn S Sillekens P Goossens H 《Journal of microbiological methods》2006,66(1):73-78
The objectives of the study were to determine the sensitivity of Nucleic Acid Sequence-Based Amplification (NASBA) for the detection of rhinovirus (RV) serotype 15 in water and in spiked respiratory specimens in the presence of a newly developed internal control (IC). The sensitivity of NASBA on RNA was 10 molecules per reaction. The sensitivity of RV NASBA on RV-15 in water and in respiratory specimens was equal to that in tissue culture. Addition of 10(4) molecules of rhinovirus internal control (RV IC) did not affect the sensitivity. Viral RNA should be extracted from clinical specimens as rapidly as possible after collection, since loss of detectable RNA occurs after 2 h. NASBA allows a sensitive detection of RV RNA in spiked respiratory specimens in the presence of an internal control. 相似文献
142.
143.
Coraline Bichet Sandra Bouwhuis Christina Bauch Simon Verhulst Peter H. Becker Oscar Vedder 《Molecular ecology》2020,29(2):429-441
Telomeres are protective caps at the end of chromosomes, and their length is positively correlated with individual health and lifespan across taxa. Longitudinal studies have provided mixed results regarding the within‐individual repeatability of telomere length. While some studies suggest telomere length to be highly dynamic and sensitive to resource‐demanding or stressful conditions, others suggest that between‐individual differences are mostly present from birth and relatively little affected by the later environment. This dichotomy could arise from differences between species, but also from methodological issues. In our study, we used the highly reliable Terminal Restriction Fragment analysis method to measure telomeres over a 10‐year period in adults of a long‐lived seabird, the common tern (Sterna hirundo). Telomeres shortened with age within individuals. The individual repeatability of age‐dependent telomere length was high (>0.53), and independent of the measurement interval (i.e., one vs. six years). A small (R2 = .01), but significant part of the between‐individual variation in telomere length was, however, explained by the number of fledglings produced in the previous year, while reproduction in years prior to the previous year had no effect. We confirmed that age‐dependent telomere length predicted an individual's remaining lifespan. Overall, our study suggests that the majority of between‐individual variation in adult telomere length is consistent across adult life, and that a smaller part of the variation can be explained by dynamic factors, such as reproduction. 相似文献
144.
Christina Bauch Marie Claire Gatt Jos Pedro Granadeiro Simon Verhulst Paulo Catry 《Molecular ecology》2020,29(7):1344-1357
Individuals in free‐living animal populations generally differ substantially in reproductive success, lifespan and other fitness‐related traits, but the molecular mechanisms underlying this variation are poorly understood. Telomere length and dynamics are candidate traits explaining this variation, as long telomeres predict a higher survival probability and telomere loss has been shown to reflect experienced “life stress.” However, telomere dynamics among very long‐lived species are unresolved. Additionally, it is generally not well understood how telomeres relate to reproductive success or sex. We measured telomere length and dynamics in erythrocytes to assess their relationship to age, sex and reproduction in Cory's shearwaters (Calonectris borealis), a long‐lived seabird, in the context of a long‐term study. Adult males had on average 231 bp longer telomeres than females, independent of age. In females, telomere length changed relatively little with age, whereas male telomere length declined significantly. Telomere shortening within males from one year to the next was three times higher than the interannual shortening rate based on cross‐sectional data of males. Past long‐term reproductive success was sex‐specifically reflected in age‐corrected telomere length: males with on average high fledgling production were characterized by shorter telomeres, whereas successful females had longer telomeres, and we discuss hypotheses that may explain this contrast. In conclusion, telomere length and dynamics in relation to age and reproduction are sex‐dependent in Cory's shearwaters and these findings contribute to our understanding of what characterises individual variation in fitness. 相似文献
145.
Bert Vandeghinste Stefaan Vandenberghe Chris Vanhove Steven Staelens Roel Van Holen 《PloS one》2013,8(7)
The aim of this study is to investigate whether reliable and accurate 3D geometrical models of the murine aortic arch can be constructed from sparse-view data in vivo micro-CT acquisitions. This would considerably reduce acquisition time and X-ray dose. In vivo contrast-enhanced micro-CT datasets were reconstructed using a conventional filtered back projection algorithm (FDK), the image space reconstruction algorithm (ISRA) and total variation regularized ISRA (ISRA-TV). The reconstructed images were then semi-automatically segmented. Segmentations of high- and low-dose protocols were compared and evaluated based on voxel classification, 3D model diameters and centerline differences. FDK reconstruction does not lead to accurate segmentation in the case of low-view acquisitions. ISRA manages accurate segmentation with 1024 or more projection views. ISRA-TV needs a minimum of 256 views. These results indicate that accurate vascular models can be obtained from micro-CT scans with 8 times less X-ray dose and acquisition time, as long as regularized iterative reconstruction is used. 相似文献
146.
Barbara Vanaelst Inge Huybrechts Nathalie Michels Maria R Flórez Maite Aramendía Lieve Balcaen Martin Resano Frank Vanhaecke Karin Bammann Silvia Bel-Serrat Stefaan De Henauw 《Biological trace element research》2013,151(3):335-343
Literature has repeatedly shown a relationship between hair minerals and metabolic health, although studies in children are currently lacking. This study aims to investigate hair levels of calcium (Ca), copper (Cu), magnesium (Mg), iron (Fe), phosphorus (P), and zinc (Zn) and their association with (1) overweight/obesity and (2) metabolic health in Flemish elementary school girls between 5 and 10 years old. Two hundred eighteen girls participated in this study as part of the baseline ChiBS project. Children were subjected to physical examinations, blood and hair sampling. Hair minerals were quantitatively determined via inductively coupled plasma–mass spectrometry after microwave-assisted acid digestion. Body mass index (BMI) and body fat percentage (BF%) were studied as anthropometric parameters, and a metabolic score (including systolic and diastolic blood pressure, insulin resistance and non-high-density lipoprotein (non-HDL) cholesterol as parameters) was calculated, with higher scores indicating a more unhealthy metabolic profile. Hair Ca, Ca/Mg, and Ca/P positively correlated with the anthropometric parameters. An inverse correlation was observed between Ca, Mg, and Ca/P in hair and the metabolic score. Inverse correlations were also observed for individual metabolic parameters (i.e., diastolic blood pressure, homeostasis model assessment for insulin resistance, non-HDL cholesterol). In particular, girls with a total number of three or more metabolic parameters above the age-specific 75th percentile showed significantly reduced hair Ca, Mg, and Ca/P concentrations. This study showed reduced hair mineral concentrations in young girls with a more unhealthy metabolic profile. Positive associations were observed between some minerals and BMI and BF%. 相似文献
147.
Phillip Gienapp Marjolein Lof Thomas E. Reed John McNamara Simon Verhulst Marcel E. Visser 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2013,368(1610)
Populations need to adapt to sustained climate change, which requires micro-evolutionary change in the long term. A key question is how the rate of this micro-evolutionary change compares with the rate of environmental change, given that theoretically there is a ‘critical rate of environmental change’ beyond which increased maladaptation leads to population extinction. Here, we parametrize two closely related models to predict this critical rate using data from a long-term study of great tits (Parus major). We used stochastic dynamic programming to predict changes in optimal breeding time under three different climate scenarios. Using these results we parametrized two theoretical models to predict critical rates. Results from both models agreed qualitatively in that even ‘mild’ rates of climate change would be close to these critical rates with respect to great tit breeding time, while for scenarios close to the upper limit of IPCC climate projections the calculated critical rates would be clearly exceeded with possible consequences for population persistence. We therefore tentatively conclude that micro-evolution, together with plasticity, would rescue only the population from mild rates of climate change, although the models make many simplifying assumptions that remain to be tested. 相似文献
148.
Sijmen A. Reijneveld P. Auke Wiegersma Johan Ormel Frank C. Verhulst Wilma A. M. Vollebergh Danielle E. M. C. Jansen 《PloS one》2014,9(4)
Objective
While adolescents use various types of care for behavioral and emotional problems, evidence on age trends and determinants per type is scarce. We aimed to assess use of care by adolescents because of behavioral and emotional problems, overall and by type, and its determinants, for ages 10–19 years.Methods
We obtained longitudinal data on 2,230 adolescents during ages 10–19 from four measurements regarding use of general care and specialized care (youth social care and mental healthcare) in the preceding 6 months, the Child Behavior Checklist (CBCL) and Youth Self-Report, and child and family characteristics. We analyzed data by multilevel logistic regression.Results
Overall rates of use increased from 20.1% at age 10/11 to 32.2% at age 19: general care was used most. At age 10/11 use was higher among boys, at age 19 among girls. Use of general care increased for both genders, whereas use of specialized care increased among girls but decreased among boys. This differential change was associated with CBCL externalizing and internalizing problems, school problems, family socioeconomic status, and parental divorce. Preceding CBCL problems predicted more use: most for mental health care and least for general care. Moreover, general care was used more frequently by low and medium socioeconomic status families, with odds ratios (95%-confidence intervals): 1.52 (1.23;1.88) and 1.40 (1.17;1.67); youth social care in case of parental divorce, 2.07 (1.36;3.17); and of special education, 2.66 (1.78;3.95); and mental healthcare in case of special education, 2.66 (1.60;4.51).Discussion
Adolescents with behavioral and emotional problems use general care most frequently. Overall use increases with age. Determinants of use vary per type. 相似文献149.
Upendra Bhojani Narayanan Devedasan Arima Mishra Stefaan De Henauw Patrick Kolsteren Bart Criel 《PloS one》2014,9(9)
Background
Weak health systems in low- and middle-income countries are recognized as the major constraint in responding to the rising burden of chronic conditions. Despite recognition by global actors for the need for research on health systems, little attention has been given to the role played by local health systems. We aim to analyze a mixed local health system to identify the main challenges in delivering quality care for diabetes mellitus type 2.Methods
We used the health system dynamics framework to analyze a health system in KG Halli, a poor urban neighborhood in South India. We conducted semi-structured interviews with healthcare providers located in and around the neighborhood who provide care to diabetes patients: three specialist and 13 non-specialist doctors, two pharmacists, and one laboratory technician. Observations at the health facilities were recorded in a field diary. Data were analyzed through thematic analysis.Result
There is a lack of functional referral systems and a considerable overlap in provision of outpatient care for diabetes across the different levels of healthcare services in KG Halli. Inadequate use of patients’ medical records and lack of standard treatment protocols affect clinical decision-making. The poor regulation of the private sector, poor systemic coordination across healthcare providers and healthcare delivery platforms, widespread practice of bribery and absence of formal grievance redress platforms affect effective leadership and governance. There appears to be a trust deficit among patients and healthcare providers. The private sector, with a majority of healthcare providers lacking adequate training, operates to maximize profit, and healthcare for the poor is at best seen as charity.Conclusions
Systemic impediments in local health systems hinder the delivery of quality diabetes care to the urban poor. There is an urgent need to address these weaknesses in order to improve care for diabetes and other chronic conditions. 相似文献150.
Joreintje D. Mackenbach Ank P. Ringoot Jan van der Ende Frank C. Verhulst Vincent W. V. Jaddoe Albert Hofman Pauline W. Jansen Henning W. Tiemeier 《PloS one》2014,9(8)
Parental harsh disciplining, like corporal punishment, has consistently been associated with adverse mental health outcomes in children. It remains a challenge to accurately assess the consequences of harsh discipline, as researchers and clinicians generally rely on parent report of young children''s problem behaviors. If parents rate their parenting styles and their child''s behavior this may bias results. The use of child self-report on problem behaviors is not common but may provide extra information about the relation of harsh parental discipline and problem behavior. We examined the independent contribution of young children''s self-report above parental report of emotional and behavioral problems in a study of maternal and paternal harsh discipline in a birth cohort. Maternal and paternal harsh discipline predicted both parent reported behavioral and parent reported emotional problems, but only child reported behavioral problems. Associations were not explained by pre-existing behavioral problems at age 3. Importantly, the association with child reported outcomes was independent from parent reported problem behavior. These results suggest that young children''s self-reports of behavioral problems provide unique information on the effects of harsh parental discipline. Inclusion of child self-reports can therefore help estimate the effects of harsh parental discipline more accurately. 相似文献