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991.
Seok-In Jang Han Young Eom Jeong Ho Hwang Lila Kim Jong-Hwa Lee 《Molecules (Basel, Switzerland)》2021,26(4)
Sialyllactose (SL), an acidic oligosaccharide, has immune-protective effects against pathogens and helps with the development of the immune system and intestinal microorganisms. To elucidate the pharmacokinetic characterization after oral administration to rats, the simultaneous quantification method for 3′-SL and 6′-SL in rat plasma was validated, using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in an electrospray ionization (ESI) mode. Several types of columns [C18, amide, and hydrophilic interaction liquid chromatography (HILIC) phase] were used to separate the peaks of 3′-SL and 6′-SL, which improved chromatographic selectivity. Ultimately, the HILIC phase column had a good peak shape and quick resolution, with a mobile phase comprising ammonium acetate buffer and acetonitrile obtained by gradient elution. In addition, the simultaneous quantification of 3′-SL and 6′-SL in rat plasma samples were adequately applied to pharmacokinetic study. 相似文献
992.
Periodontitis is a set of chronic inflammatory diseases caused by the accumulation of Gram-negative bacteria on teeth, resulting in gingivitis, pocket formation, alveolar bone loss, tissue destruction, and tooth loss. In this study, the contents of ginsenosides isolated from Panax ginseng fruit extract were quantitatively analyzed, and the anti-inflammatory effects were evaluated in human periodontal ligament cells. The major ginsenosides, Re, Ra8, and Rf, present in ginseng fruit were simultaneously analyzed by a validated method using high-performance liquid chromatography with a diode-array detector; Re, Ra8, and Rf content per 1 g of P. ginseng fruit extract was 1.01 ± 0.03, 0.33 ± 0.01, and 0.55 ± 0.04 mg, respectively. Ginsenosides-Re, -Ra8, and -Rf inhibited the production of pro-inflammatory factors and the expression of important cytokines in periodontitis by inducing the expression of heme oxygenase 1 (HO-1), promoting osteoblast differentiation of periodontal ligament cells, suppressing alveolar bone loss, and promoting the expression of osteoblast-specific genes, such as alp, opn, and runx2. An inhibitory effect of these ginsenosides on periodontitis and alveolar bone loss was observed via the regulation of HO-1 and subsequent epidermal growth factor receptor (EGFR) signaling. Silencing EGFR with EGFR siRNA confirmed that the effect of ginsenosides on HO-1 is mediated by EGFR. In conclusion, this study evaluated the contents of ginsenosides-Re, -Ra8, and -Rf isolated from P. ginseng fruit extract. Therefore, these results provide important basic data for future P. ginseng fruit component studies and suggest that ginsenosides Re, Ra8, and Rf have potential as future treatment options for periodontitis. 相似文献
993.
Jeong Han Kim Jae Hong Kim Jun-Pil Jang Jae-Hyuk Jang Deuk-Hee Jin Yong Soo Kim Hyung-Joo Jin 《Molecules (Basel, Switzerland)》2021,26(9)
Coffee has been shown to attenuate sarcopenia, the age-associated muscle atrophy. Myostatin (MSTN), a member of the TGF-β growth/differentiation factor superfamily, is a potent negative regulator of skeletal muscle mass, and MSTN-inhibition increases muscle mass or prevents muscle atrophy. This study, thus, investigated the presence of MSTN-inhibitory capacity in coffee extracts. The ethanol-extract of coffee silverskin (CSE) but not other extracts demonstrated anti-MSTN activity in a pGL3-(CAGA)12-luciferase reporter gene assay. CSE also blocked Smad3 phosphorylation induced by MSTN but not by GDF11 or Activin A in Western blot analysis, demonstrating its capacity to block the binding of MSTN to its receptor. Oral administration of CSE significantly increased forelimb muscle mass and grip strength in mice. Using solvent partitioning, solid-phase chromatography, and reverse-phase HPLC, two peaks having MSTN-inhibitory capacity were purified from CSE. The two peaks were identified as βN-arachinoyl−5-hydroxytryptamide (C20−5HT) and βN-behenoyl−5-hydroxytryptamide (C22−5HT) using mass spectrometry and NMR analysis. In summary, the results show that CSE has the MSTN-inhibitory capacity, and C20−5HT and C22−5HT are active components of CSE-suppressing MSTN activity, suggesting the potential of CSE, C20−5HT, and C22−5HT being developed as agents to combat muscle atrophy and metabolic syndrome. 相似文献
994.
Jihyun Hwang Heeju Jun Seoye Roh Seong Jae Lee Jeong Min Mun Seung Wook Kim Min-Yu Chung In-Hwan Kim Byung Hee Kim 《Molecules (Basel, Switzerland)》2021,26(11)
Herein, we prepared 1,3-dipalmitoyl-2-oleoyl glycerol (POP)-rich fats with reduced levels of diacylglycerols (DAGs), adversely affecting the tempering of chocolate, via two-step hexane fractionation of palm stearin. DAG content in the as-prepared fats was lower than that in POP-rich fats obtained by previously reported conventional two-step acetone fractionation. Cocoa butter equivalents (CBEs) were fabricated by blending the as-prepared fats with 1,3-distearoyl-2-oleoyl glycerol (SOS)-rich fats obtained by hexane fractionation of degummed shea butter. POP-rich fats achieved under the best conditions for the fractionation of palm stearin had a significantly lower DAG content (1.6 w/w%) than that in the counterpart (4.6 w/w%) prepared by the previously reported method. The CBEs fabricated by blending the POP- and SOS-rich fats in a weight ratio of 40:60 contained 63.7 w/w% total symmetric monounsaturated triacylglycerols, including 22.0 w/w% POP, 8.6 w/w% palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol, 33.1 w/w% SOS, and 1.3 w/w% DAGs, which was not substantially different from the DAG content in cocoa butter (1.1 w/w%). Based on the solid-fat content results, it was concluded that, when these CBEs were used for chocolate manufacture, they blended with cocoa butter at levels up to 40 w/w%, without distinctively altering the hardness and melting behavior of cocoa butter. 相似文献
995.
We derive a curvature identity that holds on any 6-dimensional Riemannian manifold, from the Chern-Gauss-Bonnet theorem for a 6-dimensional closed Riemannian manifold. Moreover, some applications of the curvature identity are given. We also define a generalization of harmonic manifolds to study the Lichnerowicz conjecture for a harmonic manifold “a harmonic manifold is locally symmetric” and provide another proof of the Lichnerowicz conjecture refined by Ledger for the 4-dimensional case under a slightly more general setting. 相似文献
996.
Spin‐orbit ab initio and density functional theory investigation of bismuth monoboronyl,BiBO 下载免费PDF全文
The molecular properties of bismuth monoboronyl, BiBO, were investigated using high‐level ab initio and density functional theory calculations by including the effect of spin‐orbit coupling (SOC). SOC does not cause any change in the Bi? B bond length of BiBO, by contrast it causes significant elongation of the Bi? B bond of BiBO?, by ~0.03 Å. The Bi? B bond length of BiBO? that is calculated by considering SOC is almost identical to that of BiBO; this result is consistent with a recent experimental study. The term values of excited states of BiBO calculated by including SOC are in good agreement with the experimental results. One excited state which was not assigned in the previous experimental study is the Ω = 0+ state generated by strong SOC. In the theoretical calculations on molecules containing 6p‐block elements, including SOC is crucial for obtaining results that are consistent with the corresponding experimental results. 相似文献
997.
Ho Cheol Jeong Suk Hyun Lim Youngku Sohn Young-Il Kim Hoeun Jang Dae Won Cho Patrick S. Mariano 《Tetrahedron letters》2017,58(10):949-954
Single electron transfer (SET)-promoted photoaddition reactions between fullerene C60 and both various alkyl (Me, Et, i-Pr, t-Bu)- and para-substituted (p-Me, p-OMe, p-F, p-CF3) arene ring containing, N-α-trimethylsilyl-N-alkyl-N-benzylamines were explored to gain information about photoproduct profiles and how the electronic and steric nature of the amine substrates influence reaction efficiencies. The results show that visible light (λ > 540 nm) irradiation of 10% EtOH-toluene solutions containing C60 and N-α-trimethylsilyl-N-alkyl-N-benzylamines produce 1-aminomethyl-1,2-dihydrofullerenes as a sole photoproduct. In addition, SET-promoted photoaddition reactions of unsubstituted and para-electron donating group substituted arene ring containing N-α-trimethylsilyl-N-alkyl-N-benzylamines take place to give photoproducts more efficiently than those containing para-electron withdrawing group substituted arene rings. Moreover, although steric factors are less significant than the electronic nature of the amine substrates in governing reaction efficiencies, sterics do play a significant role in photoreactions of electron deficient amine substrates. 相似文献
998.
This paper discusses the existence of at least one or two nondecreasing positive solutions for the following singular nonlinear third-order differential equation
999.
The crystallization of monodisperse linear polyethylene confined in nanoporous alumina is investigated with the calorimetric measurements. We observe a drastic change in crystallization behavior, specifically nucleation, with a decrease in the pore diameter. Crystallization in relatively larger pores with the diameters of 62 and 110 nm occurs at lower temperatures within a very narrow range, whereas crystallization in smaller pores with diameters of 15-48 nm occurs at a higher and broad range of temperatures. Nucleation and crystallization kinetics in nanopores is discussed based on classical nucleation theory as well as the Avrami theory. 相似文献
1000.
Shin H Schweinsberg A Gehring G Schwertz K Chang HJ Boyd RW Park QH Gauthier DJ 《Optics letters》2007,32(8):906-908
When a pulse superposed on a cw background propagates through an erbium-doped fiber amplifier with a negative group velocity, either pulse broadening or pulse compression can be observed. These effects can be explained in terms of two competing mechanisms: gain recovery and pulse spectrum broadening. The distortion of the pulse shape caused by these effects depends on input pulse width, pump power, and background-to-pulse power ratio. With the proper choice of these three parameters, we can obtain significant pulse advancement with minimal pulse distortion. 相似文献