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排序方式: 共有2192条查询结果,搜索用时 12 毫秒
951.
Irene Schilcher Julia T. Stadler Margarete Lechleitner Andelko Hrzenjak Andrea Berghold Gudrun Pregartner Marie Lhomme Michael Holzer Melanie Korbelius Florian Reichmann Anna Springer Christian Wadsack Tobias Madl Dagmar Kratky Anatol Kontush Gunther Marsche Saa Frank 《International journal of molecular sciences》2021,22(2)
Endothelial lipase (EL) is a strong modulator of the high-density lipoprotein (HDL) structure, composition, and function. Here, we examined the impact of EL on HDL paraoxonase 1 (PON1) content and arylesterase (AE) activity in vitro and in vivo. The incubation of HDL with EL-overexpressing HepG2 cells decreased HDL size, PON1 content, and AE activity. The EL modification of HDL did not diminish the capacity of HDL to associate with PON1 when EL-modified HDL was incubated with PON1-overexpressing cells. The overexpression of EL in mice significantly decreased HDL serum levels but unexpectedly increased HDL PON1 content and HDL AE activity. Enzymatically inactive EL had no effect on the PON1 content of HDL in mice. In healthy subjects, EL serum levels were not significantly correlated with HDL levels. However, HDL PON1 content was positively associated with EL serum levels. The EL-induced changes in the HDL-lipid composition were not linked to the HDL PON1 content. We conclude that primarily, the interaction of enzymatically active EL with HDL, rather than EL-induced alterations in HDL size and composition, causes PON1 displacement from HDL in vitro. In vivo, the EL-mediated reduction of HDL serum levels and the consequently increased PON1-to-HDL ratio in serum increase HDL PON1 content and AE activity in mice. In humans, additional mechanisms appear to underlie the association of EL serum levels and HDL PON1 content. 相似文献
952.
953.
Julia Schuler Laura Maria Neuendorf Kai Petersen Norbert Kockmann 《American Institute of Chemical Engineers》2021,67(2):e17111
Droplet generation in microfluidic devices has emerged as a promising approach for the design of highly controllable processes in the chemical and pharmaceutical industry. However, droplet generation is still not fully understood due to the complexity of the underlying physics. In this work, micro-computed tomography is applied to investigate droplet formation in a circular channel in a co-flow configuration at different flow conditions (Ca < 0.001). The application of an in-house developed scanning protocol assisted by comprehensive image processing allows for the time-resolved investigation of droplet formation. By tracking different droplet parameters (length, radii, volume, surface, Laplace pressure) the effect of flow conditions on droplet progression is determined. As characteristic for the squeezing regime, final droplet size was nearly independent of Ca for higher Ca tested. For lower Ca, the final droplet size increased with decreasing Ca, which points to the leaking regime that was recently introduced in the literature. 相似文献
954.
Corrigendum: Hybrid Photopatterned Enzymatic Reaction (HyPER) for in Situ Cell Manipulation 下载免费PDF全文
955.
Effect of sustainability information on consumers' liking of freshwater prawn (Macrobrachium rosenbergii) 下载免费PDF全文
956.
Evaluation of the impact of multivalent metal ions on the permeation behavior of Dolutegravir sodium
Julia Anita Grießinger Sabine Hauptstein Flavia Laffleur Kesinee Netsomboon 《Drug development and industrial pharmacy》2016,42(7):1118-1126
Interactions between active pharmaceutical ingredients (APIs) and polyvalent cations are an important factor within drug absorption in the gastrointestinal tract. Dolutegravir sodium, as a second-generation integrase stand transfer inhibitor for the treatment of HIV was investigated regarding chelation with Al3+, Ca2+, Fe3+, Mg2+ and Zn2+ ions at three different molar ratios. Furthermore, the influence of drug–ion chelates on the permeability of the drug across two intestinal membrane models was analyzed. For this purpose, Caco-2 monolayer model and Ussing chamber technique utilizing freshly excited rat intestinal mucosa were chosen and a buffer system without additional Mg2+ and Ca2+ ions was tested regarding cell detachment. The addition of polyvalent cations in an equal molar ratio to the drug solution decreased the dissolved drug by at least 11%. An increased multivalent cation concentration in a ratio of 1:10 afforded an API drop in the solution of at least 88% with the exception of Mg2+. In particular, Dolutegravir sodium was chelated with iron ions to nearly 100%. Overall, the higher the amount of metal ions in the solution, the lower was the detected amount of the drug. The permeation experiments across the Caco-2 monolayer and the rat intestinal mucosa pointed out that the addition of AlCl3, CaCl2 and ZnCl2 in a molar ratio of 10:1 to the drug led to significantly decreased drug permeation. According to these results the co-administration of Al3+, Ca2+ or Zn2+ as well as of supplementary medications containing these polyvalent ions is in case of oral Dolutegravir delivery not recommended. 相似文献
957.
958.
Julia Matena Svea Petersen Matthias Gieseke Andreas Kampmann Michael Teske Martin Beyerbach Hugo Murua Escobar Heinz Haferkamp Nils-Claudius Gellrich Ingo Nolte 《International journal of molecular sciences》2015,16(4):7478-7492
To improve well-known titanium implants, pores can be used for increasing bone formation and close bone-implant interface. Selective Laser Melting (SLM) enables the production of any geometry and was used for implant production with 250-µm pore size. The used pore size supports vessel ingrowth, as bone formation is strongly dependent on fast vascularization. Additionally, proangiogenic factors promote implant vascularization. To functionalize the titanium with proangiogenic factors, polycaprolactone (PCL) coating can be used. The following proangiogenic factors were examined: vascular endothelial growth factor (VEGF), high mobility group box 1 (HMGB1) and chemokine (C-X-C motif) ligand 12 (CXCL12). As different surfaces lead to different cell reactions, titanium and PCL coating were compared. The growing into the porous titanium structure of primary osteoblasts was examined by cross sections. Primary osteoblasts seeded on the different surfaces were compared using Live Cell Imaging (LCI). Cross sections showed cells had proliferated, but not migrated after seven days. Although the cell count was lower on titanium PCL implants in LCI, the cell count and cell spreading area development showed promising results for titanium PCL implants. HMGB1 showed the highest migration capacity for stimulating the endothelial cell line. Future perspective would be the incorporation of HMGB1 into PCL polymer for the realization of a slow factor release. 相似文献
959.
Julia Hain Vijayanand Chandrasekaran Thisbe K. Lindhorst 《Israel journal of chemistry》2015,55(3-4):383-386
The Mitsunobu reaction has been revisited to join hydroxyazobenzene and mannose derivatives to supply photoswitchable glycoconjugates. These are suited to modulating and controlling carbohydrate-lectin interactions, as well as to switching bacterial adhesion to surfaces. Employing hydroxyazobenzene in a Mitsunobu protocol, free mannose led to a mixture of azobenzene pyranosides and furanosides. Protected reducing mannose derivatives can give good yields of azobenzene β-D -mannopyranoside, and unprotected alkyl α-D -mannosides can be converted to 6-O-azobenzene-modified glycosides in a single step. Thus, valuable “sweet switches” can be obtained under Mitsunobu conditions, requiring a minimum (or no) protecting group chemistry. 相似文献
960.
Tian Hang Julia Glaum Toan Phung Mark Hoffman 《Journal of the American Ceramic Society》2014,97(6):1905-1911
Although piezoelectric ceramics are widely used, the structural reliability of these materials in long‐term service is still a concern. In this study, a nondestructive method for assessing material strength reliability using partial discharge (PD) tests is proposed. The PD inception electric field and the flexure strength are both controlled by the defects in the ceramics which suggests that the PD test can be an alternative nondestructive method for evaluating the structural reliability of piezoelectric ceramics. PD and four‐point flexure tests were carried out on piezoelectric ceramics. The influence of the PD test on samples was investigated by comparing the microstructure and electrical properties before and after the PD test. Samples which were not PD tested were also fractured and compared. It was found that no strength degradation was caused by the PD test. Weibull analysis revealed a correlation between the distribution in values for PD inception electric field and flexure strength. 相似文献