Search for dissertations about: "Permeability model"

Showing result 1 - 5 of 241 swedish dissertations containing the words Permeability model.

  2. 1. Intestinal absorption of drugs : The impact of regional permeability, nanoparticles, and absorption-modifying excipients

    Author : Carl Roos; Hans Lennernäs; Erik Sjögren; Martin Brandl; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Permeability; intestinal absorption; regional permeability; nanoparticles; nanosuspensions; absorption-modifying excipients; AMEs; Biofarmaci; Biopharmaceutics;

    Abstract : For successful delivery of orally given drug products, the drug compounds must have adequate solubility and permeability in the human gastrointestinal tract. The permeability of a compound is determined by its size and lipophilicity, and is usually evaluated in various pre-clinical models, including rat models. READ MORE

  4. 2. Intestinal permeability : a parameter of mucosal dysfunction

    Author : Pål Lundin; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Peptide; N-acetylcysteine; Medium-chain glyceride; Mannitol; Macromolecules; Lipid; Kinetics; In vivo; In vitro; In situ; Intestine; Injury; Inflammation; HLA-B27; HCl; Epithelium; Enhancer; dDAVP; 51Cr-EDTA; BSA; Absorption; Albumin; Permeability; Animal physiology; Djurfysiologi;

    Abstract : The gastrointestinal tract has two opposing functions; to absorb nutrients and electrolytes, and to act as a barrier towards hazardous and non-nutritional substances. In the present thesis the barrier function of the gastrointestinal tract was studied in animal models in vivo, in situ and in vitro. READ MORE

  5. 3. Intestinal Permeability and Presystemic Extraction of Fexofenadine and R/S-verapamil

    Author : Christer Tannergren; Hans Lennernäs; Dirk KF Meijer; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Biopharmacy; Bioavailability; Fexofenadine; Verapamil; P-glycoprotein; CYP3A4; OATP; Enantioselective; Permeability; Caco-2; Intestinal perfusion; Biofarmaci; Biopharmacy; Biofarmaci;

    Abstract : The main objective of this thesis was to investigate the in vivo relevance of membrane transporters and cytochrome P450 (CYP) 3A4-mediated metabolism in the intestine and liver for the bioavailability of drugs in humans after oral administration.In the first part of the thesis, the main transport mechanisms involved in the intestinal absorption and bioavailability were investigated for fexofenadine, a minimally metabolized drug, which is a substrate for P-glycoprotein (P-gp) and members of organic anion transporting polypeptide (OATP) family. READ MORE

  6. 4. Effects of Rho kinase, prostacyclin and L-arginine on microvascular permeability and perfusion

    Author : Cornelia Lundblad; Institutionen för immunteknologi; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Fysiologi; Physiology; skeletal muscle; Rho kinase; prostacyclin; permeability; NO; experimental brain trauma; brain edema; brain contusion; microcirculation; cerebral perfusion;

    Abstract : This thesis presents some effects of Rho kinase, prostacyclin (PGI2) and nitric oxide (NO) in relation to trauma and inflammation by evaluating their effects on microvascular perfusion and permeability in mouse brain and in cat skeletal muscle. PGI2 and NO are endogenous vasoactive substances produced by the endothelium. READ MORE

  7. 5. Biopharmaceutical aspects of intestinal drug absorption : Regional permeability and absorption-modifying excipients

    Author : David Dahlgren; Hans Lennernäs; Erik Sjögren; Bertil Abrahamsson; Christer Tannergren; Steffansen Bente; Uppsala universitet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; intestinal permeability; absorption-modifying excipients; Biofarmaci; Biopharmaceutics;

    Abstract : Before an orally administered drug reaches the systemic circulation, it has to dissolve in the intestinal fluids, permeate across the intestinal epithelial cell barrier, and pass through the liver. The permeation rate of drug compounds can be low and show regional differences.The thesis had two general aims. READ MORE