Isotemporal substitution evaluates hypothetical time replacement scenarios of physical movement on health, with few studies conducted among ethnically diverse preschool-aged populations. This study ...examines the reallocation of waking movement behaviors on adiposity, cardiovascular, and quality of life indicators among low-income, majority Hispanic preschool-aged youth (2-5 years) with overweight.
Participants wore an ActiGraph monitor (waist) and completed adiposity, cardiovascular, and health-related quality of life health assessments. Covariates included age, sex, ethnicity, and socioeconomic status. The isotemporal substitution approach was employed to address study aims.
Complete data were available for 131 preschoolers. For boys, reallocating 5 minutes of stationary time with light intensity, moderate to vigorous intensity, or total physical activity showed a relation with beneficial reductions in adiposity indicators; for girls, these relations were statistically null. For boys and girls, reallocating 5 minutes of stationary time -2.2 (95% CI: -3.7, -0.7) mmHg, light intensity -2.1 (95% CI: -3.7, -0.7) mmHg, or moderate intensity activity -2.7 (95% CI: -5.0, -0.4) mmHg to vigorous intensity activity was related to favorable systolic blood pressure. Reallocating 5 minutes of stationary time to moderate to vigorous intensity activity 0.6 (95% CI: -1.0, -0.1) mmHg or total physical activity -0.2 (95% CI: -0.3, -0.01) mmHg was related to lowered systolic blood pressure. Reallocating 5 minutes of stationary time to moderate to vigorous intensity activity 0.6 (95% CI: -1.1, -0.02) bpm was related to lowered resting heart rate. No significant results for quality of life were found.
Reallocation of time from stationary time to other movement behaviors is associated with several favorable adiposity and cardiovascular health outcomes among preschool children with overweight and obesity.
Agriculture affects the biogeochemical cycles of carbon, nitrogen, and phosphorus, leading to a deterioration of surface water quality. The increasing magnitude of climate change raises questions ...about potential additional or mitigating effects of climate change on this deterioration. One way to understand these potential effects is to cross‐analyze the dynamics of nutrient concentrations and hydroclimatic variables at multiple time scales. Here, we used a 16‐year data set, from a 5 km2 agricultural watershed in France with a temperate oceanic climate, that contains a daily record of nutrient concentrations and hydroclimatic variables from 2002–2017. We calculated Mann‐Kendall and Theil‐Sen tests, Fourier transforms, and daily hydroclimatic distributions associated with extreme stream concentrations to investigate long‐term trends, seasonal dynamics and their interannual variations, and the daily time scale, respectively. Dynamics of dissolved organic carbon (DOC) and nitrate (NO3) concentrations displayed opposite patterns at the three temporal scales, while soluble reactive phosphorus concentrations showed decoupled dynamics, related more to extreme hydrological events. Climate and past agricultural changes seem to have a synergetic effect that leads to long‐term NO3 decrease and DOC increase. Precipitation and, to a greater extent, watershed wetness controlled seasonal and event‐driven dynamics.
Key Points
We analysed 16 years of daily hydroclimatic and water chemistry variables in a 5 km2 agricultural watershed
Opposite temporal patterns were observed for nitrate and DOC, independent of SRP variations, at interannual, seasonal, and event time scales
Agricultural pressures and climate drive long‐term trends, while watershed wetness controls shorter‐term variations
As a phenomenon integrating climate conditions and hydrological control of the connection between streams and terrestrial dissolved organic carbon (DOC) sources, groundwater dynamics control patterns ...of stream DOC characteristics (concentrations and fluxes). Influence of intra‐annual variations in groundwater level, discharge and climatic factors on DOC concentrations and fluxes were assessed over 13 years at the headwater watershed of Kervidy‐Naizin (5 km2) in western France. Four seasonal periods were delineated within each year according to groundwater fluctuations (A: rewetting, B: high flow, C: recession, and D: drought). Annual and seasonal base flow versus stormflow DOC concentrations were defined based on daily hydrograph readings. High interannual variability of annual DOC fluxes (5.4–39.5 kg ha−1 yr−1) indicates that several years of data are required to encompass variations in water flux to evaluate the actual DOC export capacity of a watershed. Interannual variability of mean annual DOC concentrations was much lower (4.9–7.5 mg C L−1), with concentrations decreasing within each year from ca. 9.2 mg C L−1 in A to ca. 3.0 mg C L−1 in C. This indicates an intra‐annual pattern of stream DOC concentrations controlled by DOC source characteristics and groundwater dynamics very similar across years. Partial least squares regressions combined with multiple linear regressions showed that the dry season characteristics (length and drawdown) determine the mean annual DOC concentration while annual runoff determines the annual flux. Antagonistic mechanisms of production‐accumulation and dilution‐depletion combined with an unlimited DOC supply from riparian wetland soils can mitigate the response of stream concentrations to global changes and climatic variations.
Key Points:
Groundwater fluctuations divide time series into hydrological seasons
Dry season length increases production and accumulation of DOC in soils
Runoff depletes the DOC stored in watershed soils during wet seasons
Vancomycin is widely used in neonatal sepsis but proportion of newborn reaching recommended concentration is variable. Fluid status impact on vancomycin level remains understudied. We aimed to study ...fluid factors impacting vancomycin concentration at 24 h of treatment. We performed a prospective and retrospective observational monocentric study of NICU patients requiring a vancomycin treatment. We used a continuous infusion protocol, with age-appropriate loading and maintenance doses. Vancomycin target serum concentration after 24 h (C
24h
) was above 20 mg/L. Demographic, infections, and organ failure variables were analyzed as potential predictors of C
24h
. Over the study period, 70 infective episodes in 52 patients were included. At treatment initiation, the median post-natal age was 12.5 days (IQR 7–23), post menstrual age 30 weeks (IQR 28–35), and median weight 1140 g (IQR 835–1722). Germs isolated were mainly gram-positive with 73.5% being coagulase-negative
Staphylococci
. Median C
24h
was 18.7 mg/L (IQR 15.4–22.4). Overall, 41 (58.6%) treatments had a C
24h
< 20 mg/L. After multivariate analysis, higher creatinine level (OR 1.03 (95%
CI
1.002–1.06)) was associated with C
24h
≥ 20 mg/L; weight gain the day before infection (
OR
0.21 (95%
CI
0.05–0.79)) and positive biomarkers of inflammation (
OR
0.22 (0.05–0.94)) were associated with C
24h
< 20 mg/L.
Conclusion
: Vancomycin C
24h
was underdosed in 60% of patients and factors linked to changes in vancomycin pharmacokinetic such as volume of distribution and clearance, linked to creatinine level, inflammation, or weight gain, were identified.
What is Known:
• Adjustment of vancomycin regimen remains difficult due to inter- and intra-individual variability of vancomycin pharmacokinetics.
• Impact of fluid status on vancomycin concentration in critically ill neonates is incompletely studied.
What is New:
• Proportion of patients with adequate vancomycin concentration using a target adapted to nosocomial gram-positive bacteria MIC is low.
• We confirmed the role of creatinine level and report two new factors associated with low vancomycin concentration: presence of systemic inflammation and weight gain.
Cryopreservation induces many changes in sperm cells, including membrane disorders and cell death. We tested the hypothesis that apoptosis, a form of programmed cell death, can contribute to the ...fatal effect of cryopreservation on sperm cells. A multiparametric study of apoptosis on bovine sperm is proposed, using flow cytometry, including mitochondrial membrane potential (ΔΨm), caspase activation, membrane permeability, nucleus condensation, DNA fragmentation, and phosphatidylserine (PS) externalization. The relevance of each test was first validated on a human somatic cell line, U937. Cryopreservation and/or thawing induced significant changes in all apoptotic markers in living bull sperm cells except those concerning the nucleus. After cryopreservation, 44.9% ± 17% (vs. 11.3% ± 10.6% before cryopreservation) of sperm cells showed low ΔΨm, 12% ± 6.3% (vs. 2.2% ± 1.0% before) contained active caspases, and 10.8% ± 5.8% (vs. 1.4% ± 1.1% before) exhibited high membrane permeability. However, cryopreservation had no effect on DNA fragmentation (9.1% ± 7.7% before vs. 11.1% ± 5.7% after cryopreservation) or on nucleus condensation (46% ± 12.7% before vs. 43.8% ± 13.1% after). Cryopreservation acts as an apoptotic mechanism inducer in bovine sperm cells, where the earliest but not the latest features of cells undergoing apoptosis occur. We have named this abortive process an apoptosis-like phenomenon.
Summary
Sedentary behaviour is emerging as an independent risk factor for paediatric obesity. Some evidence suggests that limiting sedentary behaviour alone could be effective in reducing body mass ...index (BMI) in children. However, whether adding physical activity and diet‐focused components to sedentary behaviour reduction interventions could lead to an additive effect is unclear. This meta‐analysis aims to assess the overall effect size of sedentary behaviour interventions on BMI reduction and to compare whether interventions that have multiple components (sedentary behaviour, physical activity and diet) have a higher mean effect size than interventions with single (sedentary behaviour) component. Included studies (n = 25) were randomized controlled trials of children (<18 years) with intervention components aimed to reduce sedentary behaviour and measured BMI at pre‐ and post‐intervention. Effect size was calculated as the mean difference in BMI change between children in an intervention group and a control group. Results indicated that sedentary behaviour interventions had a significant effect on BMI reduction. The pooled effect sizes of multi‐component interventions (g = −0.060∼−0.089) did not differ from the single‐component interventions (g = −0.154), and neither of them had a significant effect size on its own. Future paediatric obesity interventions may consider focusing on developing strategies to decrease multiple screen‐related sedentary behaviours.
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