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Marcus Conrad Christian A. Sldner Heinrich Sticht 《International journal of molecular sciences》2022,23(3)
The histamine H1 receptor (H1R) is a G protein-coupled receptor (GPCR) and represents a main target in the treatment of allergic reactions as well as inflammatory reactions and depressions. Although the overall effect of antagonists on H1 function has been extensively investigated, rather little is known about the potential modulatory effect of ions or sequence variants on antagonist binding. We investigated the dynamics of a phosphate ion present in the crystal structure and of a sodium ion, for which we determined the position in the allosteric pocket by metadynamics simulations. Both types of ions exhibit significant dynamics within their binding site; however, some key contacts remain stable over the simulation time, which might be exploited to develop more potent drugs targeting these sites. The dynamics of the ions is almost unaffected by the presence or absence of doxepin, as also reflected in their small effect (less than 1 kcal·mol−1) on doxepin binding affinity. We also examined the effect of four H1R sequence variants observed in the human population on doxepin binding. These variants cause a reduction in doxepin affinity of up to 2.5 kcal·mol−1, indicating that personalized medical treatments that take into account individual mutation patterns could increase precision in the dosage of GPCR-targeting drugs. 相似文献
64.
Busarakorn Mahayothee Patchimaporn Udomkun Marcus Nagle Methinee Haewsungcharoen Serm Janjai Joachim Mueller 《European Food Research and Technology》2009,229(2):329-337
The objective of this research was to study the effect of osmotic pretreatment with combined anti-browning agents (acid, glycerol
and/or trehalose) on the colour characteristics of dried litchi after drying and during 5 months of storage compared to samples
without pretreatment. The pretreated samples showed good inhibition of polyphenol oxidase activity when compared with the
control, while the total phenolic contents in the dried products were not reduced. The results demonstrated that water activity,
lightness difference, chroma, degree of browning (DB), and 5-hydroxymethylfurfural values of all pretreated samples increased,
while hue angle decreased with storage time. Samples pretreated with glycerol showed the best potential for browning retardation,
followed by glycerol combined with trehalose, and trehalose, respectively. In addition, the colour parameters were used to
calculate the luminescence values, representing the data in grey scale, which were correlated with a non-enzymatic browning
index. The results showed grey value could be adequately used to represent the DB of dried litchi with r
2 value of 0.92. 相似文献
65.
Stefan Wagner Marcus Moser Christoph Greubel Katrin Peeper Patrick Reichart Astrid Pundt Günther Dollinger 《International Journal of Hydrogen Energy》2013
Hydrogen absorption in thin metal films clamped to rigid substrates results in mechanical stress that changes the hydrogen's chemical potential by ΔμH(σ) = −1.124σ kJ/molH for σ measured in [GPa]. In this paper we show that local stress relaxation by the detachment of niobium hydrogen thin films from the substrate affects the chemical potential on the local scale: using coincident proton–proton scattering at a proton microprobe, the hydrogen concentration is determined with μm resolution, revealing that hydrogen is not homogenously distributed in the film. The local hydrogen solubility of the film changes with its local stress state, mapping the buckled film fraction. In niobium hydrogen thin films loaded up to nominal concentrations in the two-phase coexistence region, the clamped film fraction remains in the solid solution phase, while the buckles represent the hydride phase. These results are compared to a simple model taking the stress impact on the chemical potential into account. 相似文献
66.
Kyeong Yeol Oh Jin Hwan Lee Marcus J. Curtis-Long Jung Keun Cho Jun Young Kim Woo Song Lee Ki Hun Park 《Food chemistry》2010
The seeds of Psoralea corylifolia were extracted into five different polar solvents: chloroform, 50% ethanol in water, ethanol, methanol and water. All extracts were evaluated for glycosidase inhibitory activity. The chloroform extract (CE) showed the lowest IC50 values against α-glucosidase (82.9 μg/ml) and α-mannosidase (132 μg/ml). Chromatography of CE yielded nine phenolic compounds which were identified as isovabachalcone (1), 4′-O-methylbavachalcone (2), isobavachromene (3), corylifolin (4), bavachinin (5), psoralidin (6), neobavaisoflavone (7), corylifol A (8), and bakuchiol (9). All isolated compounds, apart from compound 5, possessed α-glucosidase inhibitory activities. Among them, compounds 6–8 exhibited potent inhibition with IC50s of 13.7, 27.7 and 11.3 μM, respectively. Furthermore, compounds 2 and 6 showed α-mannosidase inhibitory activity. Mechanistic analysis of their inhibition modes against α-glucosidase showed that compounds (6 and 7) were noncompetitive, whereas compound 8 was mixed. Furthermore, the most active glycosidase inhibitors (2, 6–8) were proven to be present in the native seed in high quantities by an HPLC chromatogram. 相似文献
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Daniela Grimm Herbert Schulz Marcus Krüger Jos Luis Corts-Snchez Marcel Egli Armin Kraus Jayashree Sahana Thomas J. Corydon Ruth Hemmersbach Petra M. Wise Manfred Infanger Markus Wehland 《International journal of molecular sciences》2022,23(6)
Cancer is a disease exhibiting uncontrollable cell growth and spreading to other parts of the organism. It is a heavy, worldwide burden for mankind with high morbidity and mortality. Therefore, groundbreaking research and innovations are necessary. Research in space under microgravity (µg) conditions is a novel approach with the potential to fight cancer and develop future cancer therapies. Space travel is accompanied by adverse effects on our health, and there is a need to counteract these health problems. On the cellular level, studies have shown that real (r-) and simulated (s-) µg impact survival, apoptosis, proliferation, migration, and adhesion as well as the cytoskeleton, the extracellular matrix, focal adhesion, and growth factors in cancer cells. Moreover, the µg-environment induces in vitro 3D tumor models (multicellular spheroids and organoids) with a high potential for preclinical drug targeting, cancer drug development, and studying the processes of cancer progression and metastasis on a molecular level. This review focuses on the effects of r- and s-µg on different types of cells deriving from thyroid, breast, lung, skin, and prostate cancer, as well as tumors of the gastrointestinal tract. In addition, we summarize the current knowledge of the impact of µg on cancerous stem cells. The information demonstrates that µg has become an important new technology for increasing current knowledge of cancer biology. 相似文献
69.
介绍了COCOON手动变形机的特点.COCOON采用ATT和导丝盘等新部件,变形加工效率提高,通过节能注重对自然资源的节约.COCOON变形机达到了新的水平,它能使DTY加工商和下游加工商都受益. 相似文献
70.