Læknablaðið : fylgirit - 05.01.2015, Blaðsíða 70

X V I I V Í S I N D A R Á Ð S T E F N A H Í
F Y L G I R I T 8 2
70 LÆKNAblaðið/Fylgirit 82 2015/101
metótrexat við sóragigt hér á landi.
Efniviður og aðferðir: Fengnar voru upplýsingar úr ICEBIO-
gagnagrunninum um einstaklinga með sóragigt á sinni fyrstu meðferð
með TNFα hemli þar sem til staðar voru upplýsingar um sjúkdóms-
virkni við upphaf meðferðar og að minnsta kosti einn af eftirtöldum
tímapunktum; 13 vikur, 26 vikur eða 52 vikur (n =83). Notast var við
skilmerkin ACR20, ACR50, ACR70 og EULAR response criteria til að
meta árangur. Bornir voru saman þeir sem fengu metótrexat samhliða
TNFα hemli við þá sem aðeins fengu TNFα hemil.
Niðurstöður: Samhliða meðferð með TNFα hemli og metótrexat reynd-
ist ekki skila marktækt betri meðferðarárangri fyrr en eftir 52 vikna
meðferð. Við þann tímapunkt höfðu 18% sjúklinga á TNFα hemli, en
65% af þeim sem voru jafnframt á metótrexat náð ACR50 (p=0,0165);
fyrir ACR20 voru hlutfallið 42% og 65% (p=0,0426). Eftir 52 vikur hafði
um helmingur sjúklinga á TNFα hemli, en 92% sjúklinga á samsettri
meðferð náð góðri EULAR svörun (p=0,0004)
Ályktanir: Niðurstöður rannsóknarinnar benda til þess að sjúklingar
á samhliða meðferð með metótrexat og TNFα hemli séu líklegri til að
ná betri meðferðarárangri til langs tíma en þeir sem eingöngu fá TNFα
hemil.
V 41 Sulfobutylether-β-cyclodextrin/chitosan particles and their
physicochemical characteristics
Phennapha Saokham, Zoltán Fülöp, Þorsteinn Loftsson
Faculty of Pharmaceutical Sciences, University of Iceland
phs3@hi.is
Introduction: Chitosan particles can be prepared by a number of techni-
ques but one of the most promising one is ionotropic gelation which
is based on ionic interactions between the polycationic chitosan and a
polyanionic polymer. These anion sources can be different types of CDs,
for example sulfobutylether β-cyclodextrin (SBEβCD).
Methods and data: SBEβCD/CS particles were prepared by mixing
SBEβCD and CS solutions of equal weight concentrations. The encap-
sulation efficiency (EE) of HC in the particles, the mean hydrodynamic
diameter and polydispersity index and drug permeation were determ-
ined.
Results: The particles become larger and contain larger number of
SBEβCD molecules with increasing CS:SBEβCD ratio but at the same
time their ability to take up HC molecules decreases. The flux of HC
from the SBEβCD complexes is higher than the HC flux from the loaded
particles at identical SBEβCD concentration.
Conclusions: Due to the lipophilic nature of the CD cavities the very
hydrophilic NPs could be loaded with poorly water-soluble lipophilic
drugs such as HC. The size of the NPs (diameter 200 to 1000 nm)
and the drug release rate could be controlled by changing the initial
concentration of SBEβCD and CS during the particle preparation. In
aqueous solutions the particles were characterized as metastable whe-
reas self-assembled cyclodextrin nanoparticles readily dissociate upon
media dilution.
V 42 Stability of liposomes: effect of size, layer by layer
electrostatic deposition and dehydration
Ragnhildur Einarsdóttir1, Benjamin Zeeb2, Monika Gibis2, Kristberg Kristbergsson1,
Jochen Weiss2
1Faculty of Food Science and Nutrition, University of Iceland, 2Department of Food Physics and
Meat Science, Institute of Food Science and Biotechnology, University of Hohenheim
rae22@hi.is
Introduction: Liposomes are used as delivery systems for bioactives
in pharmaceuticals, cosmetics and foods. Liposomes subjected to
dehydration are susceptible to fusion and leakage. With the layer by
layer electrostatic depositioning, polyelectrolytes adsorb to the liposome
surface to form a monolayer. The aim of the study was to increase the
stability of liposomes through coating with cold water fish skin gelatin
and to study the influence of liposome size on layering properties and
physical stability during dehydration.
Methods and data: Liposomes were prepared with high pressure
homogenization and extrusion through polycarbonate membranes in
10 mM acetate buffer at pH 3.8 to produce three liposomal dispersions
of different sizes. Cold water skin fish gelatin was used to coat the
liposomes. Liposomal dispersions were placed in dialysis tubes where
an outer osmotic pressure created by 0.5 M sucrose, dehydrated the
samples with time.
Results: The ζ-potential changed from -55 mV for uncoated liposomes
to 25 mV for coated liposomes. The relative weight and change in size
was measured with a static light scatterer. Original size of liposomes
influenced the stability of liposomes during osmotic dehydration, with
the 0.09 µm in diameter liposomes being stable for 60 min, compared to
30 minutes for liposomes of 0.40 µm and 2.73 µm. Secondary liposomes
were more stable towards aggregation and size change.
Conclusions: The results show that cold water fish gelatin can be used
to coat liposomes using the layer by layer electrostatic dispositioning
method. Moreover it shows that the interfacial membrane protects the
liposomes from aggregation and fusion during dehydration.
V 43 New nucleosides produced by the marine sponge Geodia
macandrewi
Margarida Costa1,2, Hongbing Liu1, Eydís Einarsdóttir1,2, Margrét Þorsteinsdóttir1,2,
Sesselja Ómarsdóttir1
1Faculty of Pharmaceutical Sciences, University of Iceland, 2ArcticMass
sesselo@hi.is
Introduction: The ocean exploration for the discovery of new natural
compounds has emerged as a promising field in drug-discovery. Among
all the biological diversity, marine sponges are recognized as the richest
source of marine natural compounds. The first studies looking for mar-
ine-derived natural compounds led to the discovery of the nucleosides
spongouridine and spongothymidine, that represented the basis for
Ara-C and Ara-A. Those compounds were later commercialized as
anticancer and antiviral drugs, respectively. To date over 30 nucleosides
have been characterized from sponges and they have been shown to
possess various bioactivities.
Methods and data: In this study, the sponge Geodia macandrewi, collected
in deep waters southwest of Iceland was submitted to CH2Cl2:CH3OH
(1:1) extraction. The extract was further fractionated by modified
Kupchan solvent partition and a polar fraction revealed the presence
of several nucleosides. Those compounds were isolated by preparative
HPLC. 1D and 2D NMR spectroscopy and QTOF-MS/MS were used to