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891.
Rostislav Vecera Martin Poruba Martina Hüttl Hana Malinska Olena Oliyarnyk Irena Markova Zuzana Racova Jan Soukop Ludmila Kazdova 《Current issues in molecular biology》2022,44(5):1889
The efficacy of fenofibrate in the treatment of hepatic steatosis has not been clearly demonstrated. In this study, we investigated the effects of fenofibrate and silymarin, administered as monotherapy and in combination to existing hepatic steatosis in a unique strain of hereditary hypertriglyceridemic rats (HHTg), a non-obese model of metabolic syndrome. HHTg rats were fed a standard diet without or with fenofibrate (100 mg/kg b.wt./day) or with silymarin (1%) or with a combination of fenofibrate with silymarin for four weeks. Fenofibrate alone and in combination with silymarin decreased serum and liver triglycerides and cholesterol and increased HDL cholesterol. These effects were associated with the decreased gene expression of enzymes involved in lipid synthesis and transport, while enzymes of lipid conversion were upregulated. The combination treatment had a beneficial effect on the gene expression of hepatic cytochrome P450 (CYP) enzymes. The expression of the CYP2E1 enzyme, which is source of hepatic reactive oxygen species, was reduced. In addition, fenofibrate-induced increased CYP4A1 expression was decreased, suggesting a reduction in the pro-inflammatory effects of fenofibrate. These results show high efficacy and mechanisms of action of the combination of fenofibrate with silymarin in treating hepatic steatosis and indicate the possibility of protection against disorders in which oxidative stress and inflammation are involved. 相似文献
892.
The O-polysaccharide was isolated by mild acid hydrolysis of the lipopolysaccharide of Rahnella aquatilis 1-95 and studied by sugar and methylation analyses along with 1H and 13C NMR spectroscopy, including NOESY and 1H,13C HSQC experiments for linkage and sequence analysis. The following structure of the branched trisaccharide repeating unit of the O-polysaccharide was established: [carbohydrate structure: see text]. 相似文献
893.
894.
A cDNA encoding the Ca2+-regulated photoprotein of the bioluminescent marine hydroid Obelia geniculata was cloned and sequenced. The cDNA is a 774 bp fragment containing two overlapping open reading frames, one of which contained 585 bp encoding a 195 amino acid polypeptide which obviously has the primary structure of the apoprotein of a calcium-regulated photoprotein. Many of the residues are identical to those in other Ca2+-regulated photoproteins: 86% compared with that from Obelia longissima, 76% with that from Clytia (Phialidium), 64% with that from Aequorea, and 64% with that from Mitrocoma(Halistaura). The obelin from O. geniculata was overexpressed in Escherichia coli, refolded from inclusion bodies, and purified. The yield of highly purified recombinant protein was 55-80 mg/L of LB medium. O. geniculata obelin has absorption maxima at 280 and 460 nm and a shoulder at approximately 310 nm. The calcium-discharged protein loses visible absorption but exhibits a new absorption maximum at 343 nm. The bioluminescence of the obelin from O. geniculata is blue (lambda(max) = 495 nm). In contrast, the fluorescence of the calcium-discharged protein is yellow-green (lambda(max) = 520 nm; excitation at 340 nm). This is in sharp contrast to aequorin in which the bioluminescence and fluorescence emission spectra of the calcium-discharged protein are almost identical (lambda(max) = 465 nm). The Ca2+ concentration-effect curve for O. geniculata obelin is similar to those of many other photoproteins: at [Ca2+] below approximately 10(-8) M, calcium-independent luminescence is observed, and at [Ca2+] approximately 10(-3) M, the luminescence reaches a maximum. Between these extremes, the curve spans a vertical range of almost 8 log units with a maximum slope on a log-log plot of about 2.5. In the absence of Mg2+ the rate constant for the rise of bioluminescence determined by the stopped-flow technique is about 450 s(-1). The effects of Mg2+ on the kinetics of bioluminescence are complicated, but at all concentrations studied they are relatively small compared to the corresponding effects on aequorin luminescence. At least with respect to speed and sensitivity to Mg2+, the obelins from both O. longissima and O. geniculata would appear to be more suitable than aequorin for use as intracellular Ca2+ indicators. 相似文献
895.
Elena Matyugina Anastasia Khandazhinskaya Larisa Chernousova Sofia Andreevskaya Tatiana Smirnova Alexander Chizhov Inna Karpenko Sergey Kochetkov Ludmila Alexandrova 《Bioorganic & medicinal chemistry》2012,20(22):6680-6686
A series of new carbocyclic uracil derivatives were synthesized and evaluated as potential antituberculosis agents. Racemic 1-[4′-hydroxy-2′-cyclopenten-1′-yl]-5-tetradecynyluracil completely inhibited the growth of Mycobacterium tuberculosis H37Rv in vitro at a concentration of 10 μg/ml. Individual (+) and (?) isomers of the above uracil derivative were isolated and showed the same level of activity against two strains of Mycobacterium tuberculosis: laboratory sensitive (H37Rv) and clinical resistant to five top antituberculosis drugs (MS-115). 相似文献
896.
897.
Ludmila Ivanova Plamen Dimitrov Dora Ovcharova Jocilyn Dellava Daniel J. Hoffman 《Economics & Human Biology》2006,4(3):383-397
Major economic transitions typically entail changes in the availability of and purchasing power for different types of foods leading to long-term changes in the composition of the diet. Bulgaria, a former Eastern Bloc country, underwent a difficult and protracted transition from a centralized to market economy with acute economic crises and a much slower recovery of income levels than in Poland, the Czech Republic, and Hungary. Using annual data from the Bulgarian National Household Survey, we study changes in the reported consumption of major foods (excluding alcoholic drinks) and their constituent macronutrients from 1985 to 2002, examining also the differences in dietary patterns between the period prior to and following the transition. The consumption of most major food items decreased, resulting in a fall in per capita energy consumption of 429 kcal/day (1.80 MJ/d), following the economic transition of 1991. As expected, the consumption of foods that were more expensive per unit of energy decreased greater than cheaper foods, -34% for animal products and -19% for visible fats, but only -10% for carbohydrates. These changes are related to the changes in income and market prices as well as the general negative trend in economic growth and hyperinflation in the mid-1990s. Thus, Bulgaria experienced a decrease in food consumption without significant changes in the dietary pattern following the economic transition of 1991. The fact that part of this decline may be attributed to continued economic challenges suggests that future transitions in the diet may be expected as economic development proceeds. 相似文献
898.
Bezuglova AM Konenkova LP Doronin BM Buneva VN Nevinsky GA 《Journal of molecular recognition : JMR》2011,24(6):960-974
It was shown using enzyme-linked immunosorbent assay (ELISA) that titers of antibodies against human myelin basic protein (hMBP) in systemic lupus erythematosus (SLE) patients 4.2-fold higher than in healthy individuals, but 2.1-fold lower than in patients with multiple sclerosis (MS). Approximately 86% electrophoretically and immunologically homogeneous SLE immunoglobulin Gs (IgGs) purified using several affinity resins including Sepharose with immobilized hMBP specifically hydrolyze only hMBP but not many other tested proteins. Several rigid criteria were applied to show that the hMBP-hydrolyzing activity is an intrinsic property of SLE IgGs but not from healthy donors. In contrast to MS IgGs, abzymes from SLE patients are more sensitive to ethylenediaminetetraacetic acid and less sensitive to specific inhibitors of serine-like proteases. We present the first evidence demonstrating a significant diversity of different fractions of SLE IgGs in their affinity for hMBP-Sepharose, the ability of IgGs to hydrolyze hMBP at different optimal pHs (5-10) and be activated by different metal ions: Ca(2+) > Mg(2+) ≥ Co(2+) ≥ Fe(2+) ≥ Ni(2+) ≥ Zn(2+) ≥ Cu(2+) ≥ Mn(2+) . Combinations of Ca(2+) + Mg(2+) and Ca(2+) + Co(2) lead to a significant increase in the antibody proteolytic activity as compared with Ca(2+) , Co(2+) , or Mg(2+) ions taken separately. Our findings suggest that the immune systems of individual SLE similar to MS patients can generate a variety of anti-hMBP abzymes with different catalytic properties, which can attack hMBP of myelin-proteolipid shell of axons and play an important role in pathogenesis not only MS but also SLE patients. 相似文献
899.
Felipe Sérgio Heitor Sousa Batista Diego Silva Chagas Kristhiano Correia Ludmila Nayara Freitas Silva Tatiane Dulcineia Fortini Evandro Alexandre Silva Priscila Oliveira Otoni Wagner Campos 《Protoplasma》2019,256(6):1557-1571
Protoplasma - Ultraviolet-B (UV-B) radiation is an elicitor of secondary metabolites in plant tissue culture, but the effects on 20-hydroxyecdysone (20E) are still unclear. The 20E may show... 相似文献
900.
Korpas D Hálek J Chlupová L 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2003,147(2):181-184
The aim of this paper is to prove the possible reproducibility of measurement with a new developed device for artery elasticity monitoring and determining the standard of major pulse wave parameters. As a measurement sensor, a conic probe with thin convex membrane was used. This technique allows setting an arbitrary pressure to a measured surface artery. We measured pulse waves on the radial arteries of 108 individuals. We expected similar features in arterial wall elasticity. We concentrated primarily on the amount of subcutaneous fat. For the measured waves we evaluated five following pulse wave parameters: relative crest time, elasticity index, dicrotic wave attenuation, dicrotic wave time and interwave distance. There were no significant differences in measured pulse wave parameters among the tested groups of subjects. 相似文献