Lifestyle intervention could help obese pregnant women to limit their weight gain during pregnancy and improve their psychological comfort, but has not yet been evaluated in randomized controlled ...trials. We evaluated whether a targeted antenatal lifestyle intervention programme for obese pregnant women influences gestational weight gain (GWG) and levels of anxiety or depressed mood.
This study used a longitudinal interventional design. Of the 235 eligible obese pregnant women, 205 (mean age (years): 29±4.5; body mass index (BMI, kg m(-)(2)): 34.7±4.6) were randomized to a control group, a brochure group receiving written information on healthy lifestyle and an experimental group receiving an additional four antenatal lifestyle intervention sessions by a midwife trained in motivational lifestyle intervention. Anxiety (State and Trait Anxiety Inventory) and feelings of depression (Edinburgh Depression Scale) were measured during the first, second and third trimesters of pregnancy. Socio-demographical, behavioural, psychological and medical variables were used for controlling and correcting outcome variables.
We found a significant reduction of GWG in the brochure (9.5 kg) and lifestyle intervention (10.6 kg) group compared with normal care group (13.5 kg) (P=0.007). Furthermore, levels of anxiety significantly decreased in the lifestyle intervention group and increased in the normal care group during pregnancy (P=0.02); no differences were demonstrated in the brochure group. Pre-pregnancy BMI was positively related to levels of anxiety. Obese pregnant women who stopped smoking recently showed a significant higher GWG (β=3.04; P=0.01); those with concurrent gestational diabetes mellitus (GDM) (β=3.54; P=0.03) and those who consumed alcohol on a regular base (β=3.69; P=0.04) showed significant higher levels of state anxiety. No differences in depressed mood or obstetrical/neonatal outcomes were observed between the three groups.
A targeted lifestyle intervention programme based on the principles of motivational interviewing reduces GWG and levels of anxiety in obese pregnant women.
•Submillimetre discharge gap sizes greatly increase the CO2 conversion.•Packing materials can further increase the CO2 conversion.•Results greatly dependant on used material, gap and sphere size ...combination.•Maximum conversions of 50–55% obtained for certain combinations and flow rates.•Maximum energy efficiency of 4.3% at empty reactor and high flow rates.
DBD plasma reactors are of great interest for environmental and energy applications, such as CO2 conversion, but they suffer from limited conversion and especially energy efficiency. The introduction of packing materials has been a popular subject of investigation in order to increase the reactor performance. Reducing the discharge gap of the reactor below one millimetre can enhance the plasma performance as well. In this work, we combine both effects and use a packed-bed DBD micro plasma reactor to investigate the influence of gap size reduction, in combination with a packing material, on the conversion and efficiency of CO2 dissociation. Packing materials used in this work were SiO2, ZrO2, and Al2O3 spheres as well as glass wool. The results are compared to a regular size reactor as a benchmark. Reducing the discharge gap can greatly increase the CO2 conversion, although at a lower energy efficiency. Adding a packing material further increases the conversion when keeping a constant residence time, but is greatly dependent on the material composition, gap and sphere size used. Maximum conversions of 50–55% are obtained for very long residence times (30 s and higher) in an empty reactor or with certain packing material combinations, suggesting a balance in CO2 dissociation and recombination reactions. The maximum energy efficiency achieved is 4.3%, but this is for the regular sized reactor at a short residence time (7.5 s). Electrical characterization is performed to reveal some trends in the electrical behaviour of the plasma upon reduction of the discharge gap and addition of a packing material.
Strong electric fields are known to affect cell membrane permeability, which can be applied for therapeutic purposes, e.g., in cancer therapy. A synergistic enhancement of this effect may be ...accomplished by the presence of reactive oxygen species (ROS), as generated in cold atmospheric plasmas. Little is known about the synergy between lipid oxidation by ROS and the electric field, nor on how this affects the cell membrane permeability.
We here conduct molecular dynamics simulations to elucidate the dynamics of the permeation process under the influence of combined lipid oxidation and electroporation. A phospholipid bilayer (PLB), consisting of di-oleoyl-phosphatidylcholine molecules covered with water layers, is used as a model system for the plasma membrane.
We show how oxidation of the lipids in the PLB leads to an increase of the permeability of the bilayer to ROS, although the permeation free energy barriers still remain relatively high. More importantly, oxidation of the lipids results in a drop of the electric field threshold needed for pore formation (i.e., electroporation) in the PLB. The created pores in the membrane facilitate the penetration of reactive plasma species deep into the cell interior, eventually causing oxidative damage.
This study is of particular interest for plasma medicine, as plasma generates both ROS and electric fields, but it is also of more general interest for applications where strong electric fields and ROS both come into play.
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•Strong electric fields create pores in the cell membrane.•Lipid oxidation by ROS synergistically enhances this effect.•Lipid oxidation lowers the permeation free energy barriers of the ROS.•Lipid oxidation decreases the electric field threshold needed for pore formation.
•The impact of the packing (support) material itself cannot be neglected.•There is a large effect of the reactor setup and reactor/bead configuration.•Comparing results obtained in different reactor ...setups should be done with care.•BaTiO3 yields the best results, i.e. 25% (conversion) and 4.5% (energy efficiency).
Plasma catalysis is gaining increasing interest for CO2 conversion, but the interaction between the plasma and catalyst is still poorly understood. This is caused by limited systematic materials research, since most works combine a plasma with commercial supported catalysts and packings. In the present paper, we study the influence of specific material and reactor properties, as well as reactor/bead configuration, on the conversion and energy efficiency of CO2 dissociation in a packed bed dielectric barrier discharge (DBD) reactor. Of the various packing materials investigated, BaTiO3 yields the highest conversion and energy efficiency, i.e., 25% and 4.5%.
Our results show that, when evaluating the influence of catalysts, the impact of the packing (support) material itself cannot be neglected, since it can largely affect the conversion and energy efficiency. This shows the large potential for further improvement of packed bed plasma reactors for CO2 conversion and other chemical conversion reactions by adjusting both packing (support) properties and catalytically active sites. Moreover, we clearly prove that comparison of results obtained in different reactor setups should be done with care, since there is a large effect of the reactor setup and reactor/bead configuration.
The aggregation of insoluble amyloid beta (Aβ) peptides in the brain is known to trigger the onset of neurodegenerative diseases, such as Alzheimer's disease. In spite of the massive number of ...investigations, the underlying mechanisms to destabilize the Aβ aggregates are still poorly understood. Some studies indicate the importance of oxidation to destabilize the Aβ aggregates. In particular, oxidation induced by cold atmospheric plasma (CAP) has demonstrated promising results in eliminating these toxic aggregates. In this paper, we investigate the effect of oxidation on the stability of an Aβ pentamer. By means of molecular dynamics simulations and umbrella sampling, we elucidate the conformational changes of Aβ pentamer in the presence of oxidized residues, and we estimate the dissociation free energy of the terminal peptide out of the pentamer form. The calculated dissociation free energy of the terminal peptide is also found to decrease with increasing oxidation. This indicates that Aβ pentamer aggregation becomes less favorable upon oxidation. Our study contributes to a better insight in one of the potential mechanisms for inhibition of toxic Aβ peptide aggregation, which is considered to be the main culprit to Alzheimer's disease.
We report on multi-level atomistic simulations for the interaction of reactive oxygen species (ROS) with the head groups of the phospholipid bilayer, and the subsequent effect of head group and lipid ...tail oxidation on the structural and dynamic properties of the cell membrane. Our simulations are validated by experiments using a cold atmospheric plasma as external ROS source. We found that plasma treatment leads to a slight initial rise in membrane rigidity, followed by a strong and persistent increase in fluidity, indicating a drop in lipid order. The latter is also revealed by our simulations. This study is important for cancer treatment by therapies producing (extracellular) ROS, such as plasma treatment. These ROS will interact with the cell membrane, first oxidizing the head groups, followed by the lipid tails. A drop in lipid order might allow them to penetrate into the cell interior (e.g., through pores created due to oxidation of the lipid tails) and cause intracellular oxidative damage, eventually leading to cell death. This work in general elucidates the underlying mechanisms of ROS interaction with the cell membrane at the atomic level.
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