PubMed Health⌕ Search

Biomedical subjects

S H Hansen

Publications and source records attributed to S H Hansen.

134 records · Page 8Linked to original sources

Comparison of candicidin, levorin and trichomycin by means of high-performance liquid chromatography.

A high-performance liquid chromatographic method for the separation of individual components of polyene macrolide antibiotics has been developed. The three heptaene macrolide antibiotics, candicidin, levorin and trichomycin, have been investigated and compared. In all instances these compounds proved to be complex mixtures. It is demonstrated that candicidin and levorin are identical, whereas trichomycin differs in composition from these two substances.

Antifungal Agents↗

The role of taurine in diabetes and the development of diabetic complications.

The ubiquitously found beta-amino acid taurine has several physiological functions, e.g. in bile acid formation, as an osmolyte by cell volume regulation, in the heart, in the retina, in the formation of N-chlorotaurine by reaction with hypochlorous acid in leucocytes, and possibly for intracellular scavenging of carbonyl groups. Some animals, such as the cat and the C57BL/6 mouse, have disturbances in taurine homeostasis. The C57BL/6 mouse strain is widely used in diabetic and atherosclerotic animal models. In diabetes, the high extracellular levels of glucose disturb the cellular osmoregulation and sorbitol is formed intracellularly due to the intracellular polyol pathway, which is suspected to be one of the key processes in the development of diabetic late complications and associated cellular dysfunctions. Intracellular accumulation of sorbitol is most likely to cause depletion of other intracellular compounds including osmolytes such as myo-inositol and taurine. When considering the clinical complications in diabetes, several links can be established between altered taurine metabolism and the development of cellular dysfunctions in diabetes which cause the clinical complications observed in diabetes, e.g. retinopathy, neuropathy, nephropathy, cardiomyopathy, platelet aggregation, endothelial dysfunction and atherosclerosis. Possible therapeutic perspectives could be a supplementation with taurine and other osmolytes and low-molecular compounds, perhaps in a combinational therapy with aldose reductase inhibitors.

Animals↗

Determination of 1-hydroxypyrene in human urine by high-performance liquid chromatography.

A high-performance liquid chromatography (HPLC)/fluorescence method for quantitative analysis of 1-hydroxypyrene in urine was developed. The method validation analysis showed the method to be in analytical control. No significant systematical errors could be demonstrated. The entire run time of chromatography was 10 min using isocratic elution (acetonitrile-water, 70:30), and the retention time for 1-hydroxypyrene was 3.5 min. The short run time in combination with the low limit detection (1.37 nmol/L) makes the method potentially applicable for surveillance of pyrene exposure in work environments. The developed method is presently used for measurement of 1-hydroxypyrene in urine samples from workers exposed to a low airborne level of polycyclic aromatic hydrocarbons, generally less than 25 micrograms/m3. The urine samples of exposed workers (n = 122) showed a range of 1-hydroxypyrene from the limit of detection (LD) up to 39 nmol/L, whereas unexposed control individuals (n = 108) showed a range from LD to 3.3 nmol/L.

Chromatography, High Pressure Liquid↗

Nonaqueous capillary electrophoresis in pharmaceutical analysis.

Nonaqueous media have shown to be useful for CE separations. It is possible to obtain high selectivities of closely related compounds without using any additive in the electrophoresis medium. The physicochemical parameters of some selected solvents and their influence on separation are discussed. Separations of small compounds with equal or almost equal charge-to-mass ratios have been performed in both aqueous- and nonaqueous-based media and compared. Examples of the use of nonaqueous media for drug impurity testing are given, and precautions for obtaining quantitative and reproducible analysis in nonaqueous media are discussed.

Electrophoresis, Capillary↗