Crystallographic investigation of cetylpalmitate solid lipid nanoparticles.

Solid lipid nanoparticles (SLN) as alternative intravenous colloidal drug carriers were produced by high pressure homogenisation of the melted lipid cetylpalmitate. The crystallographic properties of the used cetylpalmitate SLN were characterised by small angle X-ray scattering (SAXS) and X-ray diffraction (XRD). It was found that the SLN are available exclusively in a crystalline form. Different cetylpalmitate formulations showed all the same patterns and a uniform crystal lattice was obtained. A partial indexing of the signals of the cetylpalmitate was carried out and the unit cell of the cetylpalmitate was estimated by the Miller indices. A preferred orientation in 001-direction was observed. This can be explained by an impressive lamellar lattice structure of the cetylpalmitate. The results were compared with the crystal data of cetylpalmitate known from literature. There was no correlation with the monoclinic structure known so far. This could indicate that the SLN consist of crystallites of another modification of the cetylpalmitate.

Differential expression of fructosyllysine-specific receptors on monocytes and macrophages and possible pathophysiological significance.

A differing individual expression of fructosyllysine-specific receptors has been found on the monocytes of 90 insulin-dependent diabetic patients and 101 healthy control subjects. The degree of receptor expression is neither age- nor sex-dependent; however, in the diabetic group it correlates significantly with the severity and age of onset of diabetic microangiopathy. To interpret the results of the human study, spontaneously diabetic and non-diabetic BB/OK rats were used to estimate tissue content of glucose-modified proteins and capillary basement membrane thickness in relation to the receptor expression on macrophages. In non-diabetic and diabetic rats no correlation was found between receptor expression and tissue content (i.e. artery, nerve) of fructosyllsine and fluorescent advanced glycation end products. However, animals which express the fructosyllysine receptor showed a greater increase in muscle capillary basement membrane thickness. There are indications that fructosyllysine receptor expression is positively associated with indices of diabetic complications such as microangiopathy and/or capillary basement membrane thickening.