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161.
Simon Glerup Maria Lume Ditte Olsen Jens R. Nyengaard Christian B. Vaegter Camilla Gustafsen Erik I. Christensen Mads Kjolby Anders Hay-Schmidt Dirk Bender Peder Madsen Mart Saarma Anders Nykjaer Claus M. Petersen 《Cell reports》2013,3(1):186-199
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162.
163.
Mary O. Hearst Kristin Biskeborn Mathew Christensen Carrie Cushing 《Obesity (Silver Spring, Md.)》2013,21(1):E26-E32
Objective:
To investigate the prevalence of overweight and obesity among white and American Indian children in a predominantly rural state.Design and Methods:
Using a repeated, cross‐sectional design of school children's height and weight, the study sample included 361,352 measures of children who were 5.0–19.9 years, attending school across 13 academic calendar years. Trained staff measured height, weight, and recorded gender, age, and race. Data were voluntarily reported to the State Department of Health.Results:
American Indian children consistently had higher rates of overweight and obesity compared to white children. Across the years, 16.3% of white students were overweight, whereas 19.3% of American Indian students were overweight. In addition, 14.5% of white children were obese and 25.9% of American Indian children were obese. Examining by rural versus urban schools, prevalence of overweight had been increasing among white male and female students and American Indian female students living in rural areas. Obesity is also increasing among rural white females and male and female American Indian children.Conclusions:
The findings here suggest that although American Indian children are at higher risk, in general, compared to white children, rural populations in general are experiencing increases in childhood overweight and obesity. Targeted rural interventions beginning at an early age are necessary to improve the health of rural children, especially in American Indian communities. 相似文献164.
Quantitative assessment of methyl‐esterification and other side reactions in a standard propionylation protocol for detection of histone modifications
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Veerle Paternoster Anders Valdemar Edhager Christian Sibbersen Anders Lade Nielsen Anders Dupont Børglum Jane Hvarregaard Christensen Johan Palmfeldt 《Proteomics》2016,16(14):2059-2063
Histone modifications play an important role in regulating chromatin stability and gene expression, but to date, investigating them remains challenging. In order to obtain peptides suitable for MS‐based analysis, chemical derivatization of N‐terminus and lysine residues by propionic anhydride is commonly performed. Several side reactions (methyl‐esterification, amidation, solvolysis, overpropionylation, and missed propionylation) during propionylation protocols have been described, yet their relative abundances remain vague. Because methyl‐esterification could interfere with correct interpretation of the modification pattern, it is essential to take measures to avoid it. Here we present in‐depth quantitative analyses of methyl‐esterification and the other side reactions in a standard propionylation protocol containing methanol, and when replacing methanol with isopropanol or acetonitrile. We show that the use of alternative solvents can eliminate methyl‐esterification and that even though other side reactions are not prevented, their contribution can be kept relatively small. We also show that replacing methanol can be of importance also in other proteomics methods, such as mixed cation exchange, using methanol under acidic conditions. 相似文献
165.
Experimental warming increases herbivory by leaf‐chewing insects in an alpine plant community
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Tone Birkemoe Saskia Bergmann Toril E. Hasle Kari Klanderud 《Ecology and evolution》2016,6(19):6955-6962
Climate warming is predicted to affect species and trophic interactions worldwide, and alpine ecosystems are expected to be especially sensitive to changes. In this study, we used two ongoing climate warming (open‐top chambers) experiments at Finse, southern Norway, to examine whether warming had an effect on herbivory by leaf‐chewing insects in an alpine Dryas heath community. We recorded feeding marks on the most common vascular plant species in warmed and control plots at two experimental sites at different elevations and carried out a brief inventory of insect herbivores. Experimental warming increased herbivory on Dryas octopetala and Bistorta vivipara. Dryas octopetala also experienced increased herbivory at the lower and warmer site, indicating an overall positive effect of warming, whereas B. vivipara experienced an increased herbivory at the colder and higher site indicating a mixed effect of warming. The Lepidoptera Zygaena exulans and Sympistis nigrita were the two most common leaf‐chewing insects in the Dryas heath. Based on the observed patterns of herbivory, the insects life cycles and feeding preferences, we argue that Z. exulans is the most important herbivore on B. vivipara, and S. nigrita the most important herbivore on D. octopetala. We conclude that if the degree of insect herbivory increases in a warmer world, as suggested by this study and others, complex interactions between plants, insects, and site‐specific conditions make it hard to predict overall effects on plant communities. 相似文献
166.
Matthew A. Christensen Laura Bettencourt Leanne Kaye Sai T. Moturu Kaylin T. Nguyen Jeffrey E. Olgin Mark J. Pletcher Gregory M. Marcus 《PloS one》2016,11(11)
BackgroundSmartphones are increasingly integrated into everyday life, but frequency of use has not yet been objectively measured and compared to demographics, health information, and in particular, sleep quality.AimsThe aim of this study was to characterize smartphone use by measuring screen-time directly, determine factors that are associated with increased screen-time, and to test the hypothesis that increased screen-time is associated with poor sleep.MethodsWe performed a cross-sectional analysis in a subset of 653 participants enrolled in the Health eHeart Study, an internet-based longitudinal cohort study open to any interested adult (≥ 18 years). Smartphone screen-time (the number of minutes in each hour the screen was on) was measured continuously via smartphone application. For each participant, total and average screen-time were computed over 30-day windows. Average screen-time specifically during self-reported bedtime hours and sleeping period was also computed. Demographics, medical information, and sleep habits (Pittsburgh Sleep Quality Index–PSQI) were obtained by survey. Linear regression was used to obtain effect estimates.ResultsTotal screen-time over 30 days was a median 38.4 hours (IQR 21.4 to 61.3) and average screen-time over 30 days was a median 3.7 minutes per hour (IQR 2.2 to 5.5). Younger age, self-reported race/ethnicity of Black and "Other" were associated with longer average screen-time after adjustment for potential confounders. Longer average screen-time was associated with shorter sleep duration and worse sleep-efficiency. Longer average screen-times during bedtime and the sleeping period were associated with poor sleep quality, decreased sleep efficiency, and longer sleep onset latency.ConclusionsThese findings on actual smartphone screen-time build upon prior work based on self-report and confirm that adults spend a substantial amount of time using their smartphones. Screen-time differs across age and race, but is similar across socio-economic strata suggesting that cultural factors may drive smartphone use. Screen-time is associated with poor sleep. These findings cannot support conclusions on causation. Effect-cause remains a possibility: poor sleep may lead to increased screen-time. However, exposure to smartphone screens, particularly around bedtime, may negatively impact sleep. 相似文献
167.
168.
Skals Marianne Greve Anne-Sofie Fagerberg Steen K. Johnsen Nanna Christensen Mette G. Praetorius Helle A. 《Purinergic signalling》2019,15(2):265-276
Purinergic Signalling - Urosepsis is a severe condition often caused by Escherichia coli that spontaneously have ascended the urinary tract to the kidneys causing pyelonephritis and potentially... 相似文献
169.
170.
Laura Kofoed Kjær Vanja Cejvanovic Trine Henriksen Torben Hansen Oluf Pedersen Cramer Kjeldahl Christensen 《Free radical research》2019,53(6):694-703
The relationship between RNA and DNA oxidation and pharmacological treatment has not been systematically investigated in patients with type 2 diabetes (T2D). We aimed to investigate the association between pharmacological treatments and levels of urinary markers of nucleic acid oxidation in T2D patients. Vejle Diabetes Biobank cohort data was nested into nationwide registry data. Multiple logistic regression was used to associate drug usage with risk of high (above median) RNA and DNA oxidation. Data from 2664 T2D patients (64% male, age range: 25–75) were included. Questionnaire-validated lipid lowering drug use was associated with low RNA oxidation (Odds ratio, OR 0.71, 95% CI: [0.59–0.87]). Insulin and non-specific antidiabetic drugs were associated with low DNA oxidation (insulin: OR 0.60, 95% CI [0.49–0.73]). Oral antidiabetics were associated with high DNA oxidation and RNA oxidation (OR 1.30, 95% CI [1.10–1.53] and OR 1.26, 95% CI [1.07–1.29]). Our findings indicate that diabetes-related drugs are associated with RNA and DNA oxidation and further studies are required to determine causality in T2D patients. 相似文献