52 research outputs found
Compositional analysis of the associations between 24-h movement behaviours and cardio-metabolic risk factors in overweight and obese adults with pre-diabetes from the PREVIEW study: cross-sectional baseline analysis
Background: Physical activity, sedentary time and sleep have been shown to be associated with cardio-metabolic
health. However, these associations are typically studied in isolation or without accounting for the effect of all
movement behaviours and the constrained nature of data that comprise a finite whole such as a 24 h day. The aim
of this study was to examine the associations between the composition of daily movement behaviours (including
sleep, sedentary time (ST), light intensity physical activity (LIPA) and moderate-to-vigorous activity (MVPA)) and
cardio-metabolic health, in a cross-sectional analysis of adults with pre-diabetes. Further, we quantified the
predicted differences following reallocation of time between behaviours.
Methods: Accelerometers were used to quantify daily movement behaviours in 1462 adults from eight countries
with a body mass index (BMI) ≥25 kg·m− 2
, impaired fasting glucose (IFG; 5.6–6.9 mmol·l
− 1
) and/or impaired glucose
tolerance (IGT; 7.8–11.0 mmol•l
− 1 2 h following oral glucose tolerance test, OGTT). Compositional isotemporal
substitution was used to estimate the association of reallocating time between behaviours. Results: Replacing MVPA with any other behaviour around the mean composition was associated with a poorer
cardio-metabolic risk profile. Conversely, when MVPA was increased, the relationships with cardiometabolic risk
markers was favourable but with smaller predicted changes than when MVPA was replaced. Further, substituting ST
with LIPA predicted improvements in cardio-metabolic risk markers, most notably insulin and HOMA-IR.
Conclusions: This is the first study to use compositional analysis of the 24 h movement composition in adults with
overweight/obesity and pre-diabetes. These findings build on previous literature that suggest replacing ST with
LIPA may produce metabolic benefits that contribute to the prevention and management of type 2 diabetes.
Furthermore, the asymmetry in the predicted change in risk markers following the reallocation of time to/from
MVPA highlights the importance of maintaining existing levels of MVPA.
Trial registration: ClinicalTrials.gov (NCT01777893)
Integrated high-content quantification of intracellular ROS levels and mitochondrial morphofunction
Oxidative stress arises from an imbalance between the production of reactive oxygen species (ROS) and their removal by cellular antioxidant systems. Especially under pathological conditions, mitochondria constitute a relevant source of cellular ROS. These organelles harbor the electron transport chain, bringing electrons in close vicinity to molecular oxygen. Although a full understanding is still lacking, intracellular ROS generation and mitochondrial function are also linked to changes in mitochondrial morphology. To study the intricate relationships between the different factors that govern cellular redox balance in living cells, we have developed a high-contentmicroscopy-based strategy for simultaneous quantification of intracellular ROS levels and mitochondrial morphofunction. Here, we summarize the principles of intracellular ROS generation and removal, and we explain the major considerations for performing quantitative microscopy analyses of ROS and mitochondrial morphofunction in living cells. Next, we describe our workflow, and finally, we illustrate that a multiparametric readout enables the unambiguous classification of chemically perturbed cells as well as laminopathy patient cells
In vivo molecular imaging of apoptosis and necrosis in atherosclerotic plaques using microSPECT-CT and microPET-CT imaging
PURPOSE: The purpose of this paper is to study molecular imaging of apoptosis and necrosis, two key players in atherosclerosis instability, using a multimodal imaging approach combining single photon emission computed tomography (SPECT), positron emission tomography (PET), and computed tomography (CT). PROCEDURES: Collar-induced carotid atherosclerosis ApoE knockout mice were imaged with 99mTc-AnxAF568 SPECT-CT to study apoptosis and sequentially with PET-CT following 124I-Hypericin (124I-Hyp) injection to visualize necrosis. RESULTS: SPECT depicted increased 99mTc-AnxAF568 uptake in both atherosclerotic carotid arteries, whereas our data suggest that this uptake is not merely apoptosis related. Although PET of 124I-Hyp was hampered by the slow blood clearance in atherosclerotic mice, 124I-Hyp was able to target necrosis in the atherosclerotic plaque. CONCLUSION: Both 99mTc-AnxAF568 and 124I-Hyp uptake are increased in atherosclerotic carotid vasculature compared to control arteries. While apoptosis imaging remains challenging, necrosis imaging can be feasible after improving the biodistribution characteristics of the probe
Synthesis and spectral properties of fluorescent dyes based on 4-styryl-1,8-naphthalimide
The paper reports on synthesis and spectroscopic study of novel Nbutyll44styryll1,88naphthall imide dyes bearing methoxy (1), dimethoxy (2), and dimethylamino (3) groups in the styryl fragg ment. It is shown that all synthesized compounds demonstrate positive solvatochromism, high values of Stokes shift in polar solvents, and fluorescence in the long wavelength part of visible range. These facts indicate a potential application of these compounds as fluorescent dyes in the biochemistry. The changes in the dipole moments of the molecules caused by excitation were estimated using Lippert—Mataga equation. The obtained results could be assigned to the formation of the excited states with intramolecular charge transfer. The formation of the twisted states with charge transfer was suggested in the case of compound 3, while the fluorescence quantum yield was significantly reduced in polar protic solvents
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