A new and relatively simple method for purification of betulin from birch bark extract was developed in this study. Its five purification steps are based on the differential solubility of extract components in various solvents and their crystallization and/or precipitation, on their affinity for Ca(OH)₂ in ethanol, and on the affinity of some impurities for silica gel in chloroform. In addition, all used solvents can be simply recycled. Betulin of more than 99% purity can be prepared by this method with minimal costs. Various observations including crystallization of betulin, changes in crystals during heating, and attempt of localization of betulin in outer birch bark are also described in this work. The original extract, fraction without betulinic acid and lupeol, amorphous fraction of pure betulin, final crystalline fraction of pure betulin and commercial betulin as a standard were employed to determine the antiproliferative/cytotoxic effect. We used WST-1 tetrazolium-based assays with triple negative breast cancer cell line BT-549. The decrease in cell survival showed clear relationship with the purity of the samples, being most pronounced using our final product of pure crystalline betulin. WST-1 proliferation/cytotoxicity test using triple negative breast cancer cell line BT-549 clearly showed the importance of purity of betulin for biological experiments and, apparently, for its medicinal use.

BACKGROUND: Cholesterol is an essential component of cell membranes, precursor of steroids, biliary acids and other components of serious importance in live organism. Cholesterol synthesis is a complicated and energy-demanding process. Real da...

Malnutrition and polypharmacy increase with age and polymorbidity and their relationship is based on a number of mechanisms. The occurrence of malnutrition in both in-patients and out-patients and its dependence on polymorbidity and age are well known, but the interrelation of polypharmacy and malnutrition has been far less investigated. The countries with the highest occurrence of polypharmacy in Europe include the Czech Republic and Finland, whereas the lowest prevalence of polypharmacy is found in Norway and the Netherlands. The occurrence, consequences and mutual relationship of malnutrition and polypharmacy are described. Up-to-date knowledge regarding the influence of drugs on nutritional status is summarized. The effect of polypharmacy on nutrition is suggested from the observations that problems with nutrition occur mostly in elderly patients, and that such patients are more frequently subject to polypharmacy. It is known that about 65% of hospitalized patients have a worse nutritional status than their healthy contemporaries. A worsened nutritional status may adversely influence the process of treatment.

Background: Omentin-1 is an anti-inflammatory adipokine produced preferentially by visceral adipose tissue. Plasma levels of omentin-1 are decreased in obesity and other insulin-resistant states. Insulin resistance contributes to the changes of cholesterol synthesis and absorption as well. The aim of this study was to characterise omentin-1 plasma levels in obese patients with diabetes mellitus type 1 during weight reduction, and to elucidate the relationship between cholesterol metabolism and omentin-1. Methods: Plasma levels of omentin-1 were measured in obese type 1 diabetics (n=14, body mass index >30 kg m⁻², age 29–62 years) by enzyme-linked immunosorbent assay (BioVendor). Gas chromatography with flame ionisation detector (Fisons Plc.,) was used to measure squalene and non-cholesterol sterols—markers of cholesterol synthesis and absorption (phase I). Measurements were repeated after 1 month (phase II; 1 week of fasting in the hospital setting and 3 weeks on a diet containing 150 g saccharides per day) and after 1 year (phase III) on a diet with 225 g saccharides per day. Results: Omentin-1 plasma levels were stable during phases I and II, but significantly increased (P<0.001) during phase III. Omentin-1 plasma dynamics were significantly associated with plasma levels of high-density lipoprotein (P=0.005) and triacylglycerols (P=0.01), as well as with lathosterol (P=0.03). Conclusion: Omentin-1 plasma levels significantly increased during the weight reduction programme. Omentin-1 plasma dynamics suggest a close relationship with cholesterol metabolism.