Sökning: "Helena Engman"

Hittade 2 avhandlingar innehållade orden Helena Engman.

  1. 1. Intestinal barriers to oral drug absorption: Cytochrome P450 3A and ABC-transport proteins

    Författare :Helena Engman; Per Artursson; Hans Lenernäs; Heyo K Kroemer; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pharmaceutics; oral drug delivery; bioavailability; human jejunum; Caco-2; ABC-transporter; P-glycoprotein; CYP3A; Galenisk farmaci; Pharmaceutics; Galenisk farmaci;

    Sammanfattning : The subject of this thesis was to study two intestinal barriers to oral drug bioavailability, drug efflux proteins of the ABC-transporter family, and in particular ABCB1/P-glycoprotein (Pgp), and the drug metabolizing enzyme cytochrome P450 (CYP) 3A4. At the onset of this thesis, similarities between CYP3A4 and Pgp in terms of their tissue distribution and gene regulation, along with overlapping substrate specificities, had generated the hypothesis that CYP3A4 and Pgp may have a complementary function and thus form a coordinated intestinal barrier to drug absorption and gut wall metabolism. LÄS MER

  3. 2. Exploring Novel Catalytic Chalcogenide Antioxidants

    Författare :Henrik Johansson; Lars Engman; Helena Grennberg; Troels Skrydstrup; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; antioxidant; tellurium; selenium; catalytic; toxicity; ROS; neutrophil; glutathione peroxidase mimic; macrophage.; Organic chemistry; Organisk kemi; Kemi med inriktning mot organisk kemi; Chemistry with specialization in Organic Chemistry;

    Sammanfattning : This thesis is concerned with the synthesis and evaluation of regenerable chalcogen containing antioxidants. Variously substituted 2,3-dihydrobenzo[b]selenophene-5-ol antioxidants were evaluated in order to gain information about structure/reactivity-relationships. LÄS MER