Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1573-904X
    Keywords: microspheres ; spray-drying ; polymer blend ; polylactic acid ; L-158-809
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Purpose. To characterize and evaluate in vitro and in vivo the release mechanisms involved in spray-dried biodegradable microspheres having differents Poly(D,L-lactide) blend formulations and containing an antihypertensive drug (L-158,809). Methods. Microspheres and blended polymers were characterized by DSC, SEM, confocal laser microspcopy and size analysis. In vitro release studies were evaluated by using microspheres made from various blends of high and low molecular weight polymer. In vivo studies were evaluated by L-158,809 antagonist ATI function versus the shift of the normal dose-response curve of blood pressure induced by Angio-tensine II. Results. The average yield of L-158,809 microspheres (10% (w/w)) was 95% of the theoritical loading. The average diameter of the microspheres was from 1 to 3 micrometers. In all release experiments, a significant burst effect (〈 15%) was observed followed by a near zero-order release kinetics. In vivo studies with two different formulations show a strong shift of angiotensin II dose-response curve. Conclusions. The release kinetics and photomicrographs suggest that the system is best described as a multi-parameter controlled released system in which the drug is molecularly dispersed. In vivo results demonstrating the controlled release of L-158,809.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 2023-2034 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Studies on post-angioplastic restenosis have shown the implication of angiotensin II (Ang) as a myoproliferative mediator. The antiproliferative efficacy of non-peptide Ang antagonists on the rat carotid model is of 50%, whereas a continuously infused peptide antagonist at low doses totally blocks neointimal growth. To explore the feasibility of depot forms of Ang that may be introduced during angioplasty and thus prevent restenois, lipid-masked Ang analogues of the following general structure were prepared: [Xxx°, Yyy1]Ang with Xxx = decanoyl or palmitoyl and Yyy = Ser, Cys, Asp, β-lactoyl, 3-mercaptopropanoyl or succinyl. All fatty acylated peptides [Xxx°, Yyy1]Ang were practically inactive, and O- or S-esterified Ser and Cys peptides underwent intramolecular transcylation giving inactive Nx-acylated peptides. O-Acylated [β-mercaptopropanoyl1]Ang were easily hydrolyzed into their biologically active[Yyy1]Ang forms, either by mild saponification or by lipase activity.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...