Effect of Structural Modification of α-Aminoxy Peptides on Their Intestinal Absorption and Transport Mechanism

Intestinal absorption of methionine and histidine was studied in adult chickens having permanent Thiry-Vella fistulas. The l isomers of both amino acids were absorbed from the fistulas more rapidly than were the d isomers. At a concentration of 10–3 m, 2,4-dinitrophenol retarded absorption of l-methionine but not of the d form. The absorption of l-histidine was impaired in the presence of equimolar concentrations of either l- or d-methionine. Racemization of d-methionine during absorption could not be demonstrated. The l isomers of both methionine and histidine appear to be absorbed from the chicken intestine by a common specific transport mechanism, with d-methionine being able to participate in at least one stage of this mechanism.

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Effect of structural modification on the gastrointestinal stability and hepatic metabolism of α-aminoxy peptides

Amino Acids ◽

10.1007/s00726-012-1291-1 ◽

2012 ◽

Vol 43 (5) ◽

pp. 2073-2085 ◽

Cited By ~ 6

Author(s):

Bin Ma ◽

Chun Yin ◽

Dan Yang ◽

Ge Lin

Keyword(s):

Structural Modification ◽

Hepatic Metabolism ◽

Aminoxy Peptides

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Enhanced intestinal absorption of asenapine maleate by fabricating solid lipid nanoparticles using TPGS: elucidation of transport mechanism, permeability across Caco-2 cell line and in vivo pharmacokinetic studies

Artificial Cells Nanomedicine and Biotechnology ◽

10.1080/21691401.2018.1546186 ◽

2019 ◽

Vol 47 (1) ◽

pp. 144-153 ◽

Cited By ~ 14

Author(s):

Mitali Patel ◽

Veenu Mundada ◽

Krutika Sawant

Keyword(s):

Intestinal Absorption ◽

Cell Line ◽

Solid Lipid Nanoparticles ◽

Transport Mechanism ◽

Lipid Nanoparticles ◽

Pharmacokinetic Studies ◽

Solid Lipid

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Effects of Vincristine on Endothelial Microtubules in the Spinal Cord

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100090270 ◽

1976 ◽

Vol 34 ◽

pp. 58-59

Author(s):

John L. Beggs ◽

John D. Waggener ◽

Wanda Miller

Keyword(s):

Spinal Cord ◽

Biological Activity ◽

Horseradish Peroxidase ◽

Transport Mechanism ◽

Vasogenic Edema ◽

Vesicular Transport ◽

Close Proximity

Microtubules (MT) are versatile organelles participating in a wide variety of biological activity. MT involvement in the movement and transport of cytoplasmic components has been well documented. In the course of our study on trauma-induced vasogenic edema in the spinal cord we have concluded that endothelial vesicles contribute to the edema process. Using horseradish peroxidase as a vascular tracer, labeled endothelial vesicles were present in all situations expected if a vesicular transport mechanism was in operation. Frequently,labeled vesicles coalesced to form channels that appeared to traverse the endothelium. The presence of MT in close proximity to labeled vesicles sugg ested that MT may play a role in vesicular activity.

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Cristal-growth dynamics of n-doped gaAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100132352 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1544-1545

Author(s):

Pham V. Huong ◽

Stéphanie Bouchet ◽

Jean-Claude Launay

Keyword(s):

Crystal Growth ◽

Spatial Resolution ◽

Epitaxial Layer ◽

Outer Surface ◽

Gaas Substrate ◽

Structural Modification ◽

Growth Dynamics ◽

Argon Laser ◽

High Anisotropy ◽

Crystal Gaas

Microstructure of epitaxial layers of doped GaAs and its crystal growth dynamics on single crystal GaAs substrate were studied by Raman microspectroscopy with a Dilor OMARS instrument equipped with a 1024 photodiode multichannel detector and a ion-argon laser Spectra-Physics emitting at 514.5 nm.The spatial resolution of this technique, less than 1 μm2, allows the recording of Raman spectra at several spots in function of thickness, from the substrate to the outer deposit, including areas around the interface (Fig.l).The high anisotropy of the LO and TO Raman bands is indicative of the orientation of the epitaxial layer as well as of the structural modification in the deposit and in the substrate at the interface.With Sn doped, the epitaxial layer also presents plasmon in Raman scattering. This fact is already very well known, but we additionally observed that its frequency increases with the thickness of the deposit. For a sample with electron density 1020 cm-3, the plasmon L+ appears at 930 and 790 cm-1 near the outer surface.

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