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61.
Magdalena Paczkowska Miko?aj Mizera Hanna Piotrowska Daria Szymanowska-Powa?owska Kornelia Lewandowska Joanna Goscianska Robert Pietrzak Waldemar Bednarski Zbigniew Majka Judyta Cielecka-Piontek 《PloS one》2015,10(3)
This study aimed to obtain and characterize an RU-β-CD complex in the context of investigating the possibility of changes in the solubility, stability, antioxidative and microbiological activity as well as permeability of complexated rutin as against its free form. The formation of the RU-β-CD complex via a co-grinding technique was confirmed by using DSC, SEM, FT-IR and Raman spectroscopy, and its geometry was assessed through molecular modeling. It was found that the stability and solubility of the so-obtained complex were greater compared to the free form; however, a slight decrease was observed inits antibacterial potency. An examination of changes in the EPR spectra of thecomplex excluded any reducing effect of complexation on the antioxidative activity of rutin. Considering the prospect of preformulation studies involving RU-β-CD complexes, of significance is also the observed possibility of prolongedly releasing rutin from the complex at a constant level over along period of 20 h, and the fact that twice as much complexated rutin was able topermeate compared to its free form. 相似文献
62.
Bánóczi Z Gorka-Kereskényi Á Reményi J Orbán E Hazai L Tökési N Oláh J Ovádi J Béni Z Háda V Szántay C Hudecz F Kalaus G Szántay C 《Bioconjugate chemistry》2010,21(11):1948-1955
Vinblastine is a widely used anticancer drug with undesired side effects. Its conjugation with carrier molecules could be an efficient strategy to reduce these side effects. Besides this, the conjugate could exhibit increased efficiency against resistant cells, e.g., due to the altered internalization pathway. Oligoarginines, as cell-penetrating peptides, can transport covalently attached compounds into different kinds of cells and enhance the efficiency of those compounds. We report here the coupling of vinblastine through its carboxyl group at position 16 with the N-terminal amino function of L-Trp methyl ester. After hydrolysis of the ester group, 17-desacetylvinblastineTrp was conjugated to the N-terminal amino group of oligoarginine via the C-terminal carboxyl group of the Trp moiety in solution. The antitumor effect of conjugates was studied on sensitive and resistant human leukemia (HL-60) cells in vitro. Our data suggest that all conjugates investigated possess an antiproliferative effect against the studied cells. However, the effect was dependent on the number of Arg residues in the conjugates: Arg? > Arg? ? Arg?. The conjugate with Arg? exhibited similar efficicacy as compared with free 17-desacetylvinblastineTrp. The in vitro studies also showed that the tubulin binding ability of vinblastine was essentially preserved even in the octaarginine conjugate. We also observed that two isomers were formed during conjugation. These isomers showed different levels of activity against tubulin polymerization in vitro and in vivo. The 17-desacetylvinblastineTrp-Arg?-1 isomer conjugate possessed high selectivity against the mitotic spindles. HRMS and NMR data suggest that 17-desacetylvinblastineTrp-Arg?-1 and 17-desacetylvinblastineTrp-Arg?-2 are epimers at the tryptophan α carbon atom. 相似文献
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Adrienn Guóth Dániel Benyó Jolán Csiszár Ágnes Gallé Ferenc Horváth László Cseuz László Erdei Irma Tari 《Acta Physiologiae Plantarum》2010,32(4):719-727
The effects of increasing osmotic stress induced by 100–400 mOsm (−0.976 MPa) polyethylene glycol (PEG 6000) were investigated
in a drought-tolerant (Triticum aestivum L. cv. Mv Emese) and drought-sensitive (cv. GK élet) wheat cultivar at the three-leaf stage. During osmotic stress, the decline
of the water potential (ψ
w) was more significant in the leaves, while the abscisic acid (ABA) levels of the roots increased earlier and remained higher
in the sensitive than in the tolerant variety. There was an increasing gradient of ABA content toward the youngest leaves
in the drought-sensitive GK élet, while more ABA accumulated in the fully developed, older leaves of the tolerant cultivar
Mv Emese. In accordance with the rapid and significant accumulation of ABA, the stomatal conductance decreased earlier in
the tolerant cultivar. The effect of water stress on the PSII photochemistry was pronounced only 1 week after the exposure
to PEG, as indicated by the earlier decrease of the net CO2 fixation, the effective quantum yield (ΦPSII) and the photochemical quenching (q
P) in light-adapted samples of the tolerant variety in 400 mOsm PEG 6000. The stress treatment caused more significant reductions
in these parameters toward the end of the experiment in the sensitive cultivar. In spite of small differences in the photosynthetic
characteristics, the net biomass production was not significantly altered by this osmotic stress. The accumulation of ABA
controlled the distribution of the biomass between the shoot and root systems under osmotic stress, and contributed to the
development of stronger and deeper roots in the drought-sensitive cultivar GK élet. However, the root elongation did not correlate
with the drought sensitivity of these cultivars on the basis of crop yield. 相似文献
65.
Rita Szabó Zoltán Bánóczi Gábor Mező Orsolya Láng László Kőhidai Ferenc Hudecz 《生物化学与生物物理学报:生物膜》2010,1798(12):2209-2216
We have developed a group of water-soluble drug conjugates in which daunomycin (Dau) is coupled to cationic, amphoteric or anionic branched polypeptides and a new conjugate containing a cationic polypeptide carrier modified with a cell penetrating octaarginine. We investigated in vitro physiological activity of these conjugates in several aspects: in vitro cytotoxicity and cytostatic effect, adhesion and cellular uptake were examined on murine (J774 and L1210) and human (MonoMac6 and HL-60) leukemia cell lines and on murine bone marrow derived macrophages. We found that these processes are dependent on the properties of the carrier, on experimental conditions like concentration and incubation time. We found that attachment of polypeptide and cell penetrating peptide to the bioactive agent, depending on the cell line, could significantly improve the antitumor activity of the drug. 相似文献
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70.
Gender differences in biomechanical properties of intramural coronary resistance arteries of rats, an in vitro microarteriographic study 总被引:1,自引:0,他引:1
Matrai M Mericli M Nadasy GL Szekeres M Varbiro S Banhidy F Acs N Monos E Szekacs B 《Journal of biomechanics》2007,40(5):1024-1030
The prevalence of ischemic heart disease is lower in premenopausal females than in males of corresponding age. This should be related to gender differences in coronary functions. We tested whether biomechanical differences exist between intramural coronary resistance arteries of male and female rats. Intramural branches of the left anterior descending coronary artery (uniformly approximately 200microm in diameter) were isolated, cannulated and studied by microarteriography. Intraluminal pressure was increased from 2 to 90mmHg in steps and steady-state diameters were measured. Measurements were repeated in the presence of vasoconstrictor U46619 (10(-6)M) and the endothelial coronary vasodilator bradykinin (BK) (10(-6)M). Finally, passive diameters were recorded in calcium-free saline. A similar inner radius and a higher wall thickness (41.5+/-2.9microm vs. 31.4+/-2.7microm at 50mmHg in the passive condition, p<0.05) resulted in lower tangential wall stresses in male rats (18.9+/-1.9kPa vs. 24.9+/-2.5kPa at 50mmHg, p<0.05). Isobaric elastic modulus of vessels from male animals was significantly smaller at higher pressures. Vasoconstrictor response was significantly stronger in male than in female animals. Endothelial relaxations induced by BK were not different. This is the first demonstration that biomechanical characteristics of intramural coronary resistance arteries of a mammalian species are different in the male and female sexes. Higher wall thickness and higher vascular contractility in males are associated with similar endothelial function and larger high-pressure elasticity compared to females. These gender differences in biomechanics of coronary resistance arteries of rats may contribute to our better understanding the characteristic physiological and pathological differences in humans. 相似文献