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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 793 records · Page 44
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Soluble FLT-1 rules placental destiny

Highlights: • Placenta previa is an obstetric complication which can cause massive hemorrhage. • Some pregnant women recover from placenta previa due to a phenomenon called “migration” of the placenta. • The sFLT-1 expression level is locally high in the caudal part of the human placenta in patients with placenta previa. • In mice, sFlt-1 expression level was significantly increased by ablation of uterine arteries. • Our study suggests that “migration” of the placenta is derived from placental degeneration and sFlt-1 plays an important role in placental degeneration. Placenta previa is an abnormality in which the placenta covers the internal uterine os, and it can cause serious morbidity and mortality in both mother and fetus due to catastrophic hemorrhage. Some pregnant women recover from placenta previa due to a phenomenon called “migration.” However, the mechanism of “migration” of the placenta has not been elucidated.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Sesaminol diglucoside, a water-soluble lignan from sesame seeds induces brown fat thermogenesis in mice

Highlights: • Aqueous extract of black sesame seeds induces brown fat thermogenesis in mice. • SDG purified from the aqueous sesame extract prevents weight gain in HFD fed mice. • SDG induces brown fat thermogenesis through β3-adrenergic receptors. Brown adipose tissue (BAT) is the site of non-shivering thermogenesis in mammals, wherein energy is dissipated as heat. We observed that aqueous extract of black sesame seed triggers an increase in the expression of Uncoupling Protein 1 (UCP1) in brown adipocytes from mice. The active component from the extract was purified and identified to be sesaminol diglucoside (SDG). SDG treatment decreased mass of white fat pads and serum glucose levels and increased UCP1 levels in BAT thereby protecting mice against high fat induced weight gain. Further in silico and in vitro studies revealed that these effects are due to the agonist like behaviour of SDG towards beta 3 adrenergic receptors (β3-AR). Together, our results suggest that SDG induces BAT mediated thermogenesis through β3-AR and protects mice against diet-induced obesity.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2013

Water-soluble drug partitioning and adsorption in HEMA/MAA hydrogels

Two-photon confocal microscopy and back extraction with UV/Vis-absorption spectrophotometry quantify equilibrium partition coefficients, k, for six prototypical drugs in five soft-contact-lens-material hydrogels over a range of water contents from 40 to 92%. Partition coefficients were obtained for acetazolamide, caffeine, hydrocortisone, Oregon Green 488, sodium fluorescein, and theophylline in 2-hydroxyethyl methacrylate/methacrylic acid (HEMA/MAA, pK a ≈ 5.2) copolymer hydrogels as functions of composition, aqueous pH (2 and 7.4), and salinity. At pH 2, the hydrogels are nonionic, whereas at pH 7.4, hydrogels are anionic due to MAA ionization. Solute adsorption on and nonspecific electrostatic interaction with the polymer matrix are pronounced. To express deviation from ideal partitioning, we define an enhancement or exclusion factor, E≡k/φ 1 , where φ 1 is hydrogel water volume fraction. All solutes exhibit E>1 in 100wt % HEMA hydrogels owing to strong specific adsorption to HEMA strands. For all solutes, E significantly decreases upon incorporation of anionic MAA into the hydrogel due to lack of adsorption onto charged MAA moieties. For dianionic sodium fluorescein and Oregon Green 488, and partially ionized monoanionic acetazolamide at pH 7.4, however, the decrease in E is more severe than that for similar-sized nonionic solutes. Conversely, at pH 2, E generally increases with addition of the nonionic MAA copolymer due to strong preferential adsorption to the uncharged carboxylic-acid group of MAA. For all cases, we quantitatively predict enhancement factors for the six drugs using only independently obtained parameters. In dilute solution for solute i , E i is conveniently expressed as a product of individual enhancement factors for size exclusion (E$_i^{ex}$), electrostatic interaction (E$_i^{el}$), and specific adsorption (E$_i^{ad}$):E$_i$≡E$_i^{ex}$E$_i^{el}$E$_i^{ad}$. Finally, to obtain the individual enhancement factors, we employ an extended Ogston mesh-size distribution for Eiex; Donnan equilibrium for E$_i^{el}$; and Henry's law characterizing specific adsorption to the polymer chains for E$_i^{ad}$. Predicted enhancement factors are in excellent agreement with experiment.

back extraction↗
DOE OSTI2018

Corrigendum to “Experimental Determination of Solubilities of Di-calcium Ethylenediaminetetraacetic Acid Hydrate [Ca 2 C 10 H 12 N 2 O 8 •7H 2 O(s)] in NaCl and MgCl 2 Solutions to High Ionic Strengths and Its Pitzer Model: Applications to Geological Disposal of Nuclear Waste and Other Low Temperature Environments”

In the published version (Xiong et al., 2017), there was an error for the reaction coefficient for the dissolution reaction of Ca 2 C 10 H 12 N 2 O 8 •7H 2 O(s) in the database used for the modeling. In the database for the modeling, the coefficient for water (i.e., 7H 2 O) was inadvertently omitted.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Beyond the wall: High-throughput quantification of plant soluble and cell-wall bound phenolics by liquid chromatography tandem mass spectrometry

Plants accumulate several thousand of phenolic compounds, including lignins and flavonoids, which are mainly synthesized through the phenylpropanoid pathway, and play important roles in plant growth and adaptation. A novel high-throughput ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was established to quantify the levels of 19 flavonoids and 15 other phenolic compounds, including acids, aldehydes, and alcohols. The chromatographic separation was performed in 10 minutes, allowing for the resolution of isomers such as 3-, 4-, and 5-chlorogenic acids, 4-hydroxybenzoic and salicylic acids, isoorientin and orientin, and luteolin and kaempferol. The linearity range for each compound was found to be in the low fmol to the high pmol. Furthermore, this UHPLC-MS/MS approach was shown to be very sensitive with limits of detection between 1.5 attomoles to 300 fmoles, and limits of quantification between 5 attomoles to 1,000 fmoles. Extracts from maize seedlings were used to assess the robustness of the method in terms of recovery efficiency, matrix effect, and accuracy. The biological matrix did not suppress the signal for 32 out of the 34 metabolites under investigation. Additionally, the majority of the analytes were recovered from the biological samples with an efficiency above 75 %. All flavonoids and other phenolic compounds had an intra- and inter-day accuracy within a ± 20 % range, except for coniferyl alcohol and vanillic acid. Finally, the quantification of flavonoids, free and cell wall-bound phenolics in seedlings from two maize lines with contrasting phenolic content was successfully achieved using this methodology.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗