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It was demonstrated that the process of hemolysis of erythrocytes induced by resorcinolic lipids is inhibited by divalent cations present in the incubation medium. The extent of inhibition is dependent on the nature of both type of the cation and the hemolytic agent. Lysis most susceptible to divalent cations is that induced by short (C15) and medium-chained (C19) 5-n-alkylresorcinols, which also have the highest observed hemolytic potencies. Furthermore, the protection was the stronger the stronger lytic activity was exerted by studied compound. The homologs with the longest side chain studied, although exhibiting the lowest hemolytic activity by themself, were the least susceptible to inhibition of their hemolytic activity by cations. The effect of cobalt cation has been found to be intermediate between the effect of Mn2+ and Zn2+. The most effective in protection of erythrocytes was Zn2+ which almost completely protected the cells against alkylresorcinol-induced lysis at the concentrations of 10-6 M and above.
The effect of divalent cations in concentrations 10-9-10-3M upon the hemolysis of sheep erythrocytes induced by resorcinolic lipids was studied. It was demonstrated that the process of hemolysis is inhibited by divalent cations present in the incubation medium. The extent of inhibition is dependent on both type of the cation and hemolytic agent. In alkylresorcinol-induced hemolysis the most effective in protection of the cells were Zn2+ and Co2+ cations. Weaker protective action was observed for Cd2+ and Mn2+. Calcium ions, in all studied concentrations, were without marked effect on the level of relative hemolysis. Magnesium ions as well as Ba2+ in nanomolar concentrations were effective inhibitors of the lysis but this effect diminished at higher (millimolar) concentrations of these ions. When alkenylresorcinols were used as hemolysis-inducers no effective protection of erythrocytes by Ca2+, Ba2+ or Mg2+ was observed. Most effective in protection of cells against this amphiphile-induced lysis, similarly to their effect observed previously for various lytic agents, were cations of Zn2+, Co2+ and Cd2+. Mn2+ cations were intermediate, with respect to their protective potency.
Background. Rosemary (Rosmarinus officinalis L.) extracts have a potent antioxidant and antibacterial activity and are widely used in the food industry. The effect of added rosemary preparations on the microbiological quality and process of lipid oxidation of model pork batters, immediately after preparation (“0”) and 1, 3 and 7 days of chillstorage (4-6°C) was analysed in the study. Material and methods. Experiments were conducted with three types of rosemary preparations, i.e.: dried spice, essential oil and a commercial preparation (TasteGuard P). The experimental material consisted of meat batter produced from porcine musculus longissimus dorsi and water. Microbiological examinations covered determinations of the total count of mesophilic aerobic microorganisms, psychrophilic bacteria, coliforms and enterococci. In tum, chemical analyses involved determination of the TBARS value. Results. The rosemary preparations did not exhibit either antibacterial properties against aerobic mesophilic or psychrophilic bacteria. The essential rosemary oil was observed to inhibit the growth of coliform bacteria and enterococci, whereas the dried spice examined was found to increase the counts of aerobic mesophilic bacteria, coliforms and enterococci. None of the rosemary preparations terminated the lipid oxidation process. Conclusions. The results obtained in this study point to the necessity of continuing inves- tigations to determine the dose of rosemary preparations that would inhibit the growth of microflora being the most frequent cause of raw materials and products spoilage and, simultaneously, restrict oxidation of their lipids.
Almost from the time of their rediscovery in the 60's and the demonstration of their entrapment potential, liposomal vesicles have drawn attention of researchers as potential carriers of various bioactive molecules that could be used for therapeutic applications in humans and animals. Several commercial liposome-based drugs have already been discovered, registered and introduced with great success on the pharmaceutical market. However, further studies, focusing on the elaboration of more efficient and stable amphiphile-based vesicular (or non-viral) drug carriers are still under investigation. In this review we present the achievements of our group in this field. We have discovered that natural amphiphilic dihydroxyphenols and their semisynthetic derivatives are promising additives to liposomal lipid compositions. The presence of these compounds in lipid composition enhances liposomal drug encapsulation, reduces the amount of the lipid carrier necessary for efficient entrapment of anthracycline drugs by a factor of two, stabilizes liposomal formulation of the drug (both in suspension and in a lyophilized powder), does not influence liposomal fate in the blood circulation system and benefits from other biological activities of their resorcinolic lipid modifiers.
Heracleum sosnowskyi Manden of Caucasian origin is the most dangerous plant for the environment, geosystems, farming and public health. The sap of H. sosnowskyi, its pollen, scent and even dew are dangerous for human health and cause chemical burns, allergic reactions and even deaths. Works on the negative impact of the H. sosnowskyi spread have been published in Ukraine only recently. A more detailed study of H. sosnowskyi is possible only through inspections of each region in Ukraine, which would allow to predict the intensity, rate, frequency and area of phytocoenotic changes, as well as to provide data for cartograms. In the Rivne region, H. sosnowskyi overcomes geographical, ecological, reproductive and coenotic barriers, forms a large number of offspring,massively and rapidly spreads over considerable distances of the studied territory, establishing in anthropogenic and natural coenoses. The dense river network, sufficient moisture, mild climate and the decline of agriculture have created favourable conditions for the spread of H. sosnowskyi.Populations of H. sosnowskyi in the Rivne region have an uneven distribution. The southern part of the oblast has the highest concentration of H. sosnowskyi populations was not found in only three northern districts of the Rivne region. This can be explained by the poor quality of soil. In the central part of the region, the highest concentration of H. sosnowskyi populations was found in the southern and western parts of the city of Rivne. The presence of a large number of springs, rivers and the relief of the Rivne region does not allow the use of chemical plant control methods, as this can lead to significant contamination with herbicides. The most effective method is systematic cutting of shoots prior to flowering and trimming at the root collar.
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