PubMed · 10454941
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
C Mertz. 1999. Product clarification.. https://doi.org/10.1016/s0889-5406(99)70117-4
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
The aim of the study was to develop a mucoadhesive ocular insert for the controlled delivery of ophthalmic drugs and to evaluate its efficacy in vivo. The inserts tested were based either on unmodified or thiolated poly(acrylic acid). Water uptake and swelling behavior of the inserts as well as the drug release rates of the model drugs fluorescein and two diclofenac salts with different solubility properties were evaluated in vitro. Fluorescein was used as fluorescent tracer to study the drug release from the insert in humans. The mean fluorescein concentration in the cornea/tearfilm compartment as a function of time was determined after application of aqueous eye drops and inserts composed of unmodified and of thiolated poly(acrylic acid). The acceptability of the inserts by the volunteers was also evaluated. Inserts based on thiolated poly(acrylic acid) were not soluble and had good cohesive properties. A controlled release was achieved for the incorporated model drugs. The in vivo study showed that inserts based on thiolated poly(acrylic acid) provide a fluorescein concentration on the eye surface for more than 8 h, whereas the fluorescein concentration rapidly decreased after application of aqueous eye drops or inserts based on unmodified poly(acrylic acid). Moreover, these inserts were well accepted by the volunteers. The present study indicates that ocular inserts based on thiolated poly(acrylic acid) are promising new solid devices for ocular drug delivery.
P-selectin blocking potency was investigated using synthetic monomeric and polymeric anionic compounds containing sulfate groups such as O-sulfotyrosine (sTyr) and/or sulfated Lewis structures. A non-carbohydrate-containing polyacrylamide conjugate sTyr-PAA (80% mol of sTyr) was a remarkably potent inhibitor of P-selectin binding in vitro, having an IC(50) value of 6 ng/mL (equivalent to 10 nM calculated on the basis of sTyr residues or 0.1 nM calculated by the mass of the macromolecule). The inhibitory effect of sTyr-PAA (80%) towards P-selectin is significantly greater than that of fucoidan (IC(50), 100 ng/mL). However, sTyr-PAA (80%) was less effective than fucoidan at reducing neutrophil extravasation in an in vivo rat model of peritonitis.
Thermoresponsive nanocomposite thin films composed of alternating layers of silica and polymerized N-isopropylacrylamide (NIPAM) or NIPAM plus dodecyl methacrylate (DM) hydrogels were prepared by surfactant-directed evaporation-induced self-assembly (EISA). During EISA, the organic monomers partition within the hydrophobic domains of a lamellar mesophase. In-situ polymerization via a free radical process results in a 1-2 nm thick hydrogel phase sandwiched between layers of silica oriented parallel to the substrate surface. The thermoresponsiveness of PNIPAM is preserved in this confined environment, and the polymeric layers reversibly swell and deswell by a factor of 2 in water upon temperature changes around the transition temperature of PNIPAM (32 degrees C). The composition, mesostructure, and environmental response were studied by detailed NMR, TGA, and SAXS analyses.