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191.
Zana Besser Silconi Sasa Benazic Jelena Milovanovic Milena Jurisevic Dragana Djordjevic Milos Nikolic Marina Mijajlovic Zoran Ratkovic Gordana Radić Snezana Radisavljevic Biljana Petrovic Gordana Radosavljevic Marija Milovanovic Nebojsa Arsenijevic 《Transition Metal Chemistry》2018,43(8):719-729
A series of complexes of platinum(IV) (C1–C5) and zinc(II) (C6–C10) with S-alkyl derivatives of thiosalicylic acid were prepared and characterized. The interactions of the complexes with calf thymus DNA were analyzed by absorption (UV–Vis) and emission spectral studies (ethidium bromide displacement studies). The cytotoxic activities of complexes C1–C10 were determined against mouse B cell lymphocytic leukemia cells (BCL1), human B-prolymphocytic leukemia (JVM-13), mouse mammary carcinoma cells (4T1), and human mammary carcinoma cells (MDA-MB-468) and compared to the activities of the free ligand precursors and cisplatin. The cytotoxicities of the platinum(IV) and zinc(II) complexes toward mouse tumor cell lines were higher compared with their effects on human tumor cell lines. The zinc(II) complex C9 showed the highest antitumor activity toward the tested human cell lines, while the platinum(IV) complex C4 exhibited the highest antitumor activity toward mouse BCL1 and 4T1 cells. Both C4 and C9 have ligands derived from S-propyl thiosalicylic acid. 相似文献
192.
Dušan Lj. Tomović Andriana M. Bukonjić Verica V. Jevtić Zoran R. Ratković Jovana V. Bogojeski Ana Đeković Ivana D. Radojević Ljiljana R. Čomić Slađana B. Novaković Goran A. Bogdanović Srećko R. Trifunović Gordana P. Radić Snežana Cupara 《Transition Metal Chemistry》2018,43(2):137-148
The biological activities of two binuclear copper(II) complexes containing S-alkenyl derivatives of thiosalicylic acid are reported [alkenyl = propenyl (L1), isobutenyl (L2)]. The structure of the complex with the S-isobutenyl derivative (C2) was confirmed by single-crystal X-ray structure analysis, which revealed that the structure consists of centrosymmetric, dinuclear complex molecules [Cu2(S-i-butenyl-thiosal)4(DMSO)2] containing two Cu(II) centers bridged by four S-isobutyl-thiosalicylate ligands in a paddle-wheel type structure. The Cu(II) atom is situated in a distorted square-pyramidal environment formed by carboxylate oxygen atoms in the basal plane and a DMSO ligand in the axial position. The reactivities of the complexes toward guanosine-5′-monophosphate (5′-GMP) were investigated. Complex C2 ([Cu2(S-i-butenyl-thiosal)4(H2O)2]) reacted more rapidly with 5′-GMP than complex C1. The interactions of complexes C1 and C2 with calf thymus DNA (CT-DNA) were examined by absorption (UV–Vis) and emission spectral studies (ethidium bromide displacement studies), revealing good DNA interaction abilities. The antimicrobial activities of the free ligands and their complexes were tested by microdilution method, and both minimal inhibitory and microbicidal concentrations were determined. All the tested substances demonstrated selective and moderate antibacterial activity on gram-positive bacteria, but low antibacterial activity on gram-negative bacteria. Also, the tested substances demonstrated low antifungal activity. 相似文献
193.
Ana Damjanovi Branka Kolundija Ivana Z. Mati Ana Krivokua Gordana Zduni Katarina avikin Radmila Jankovi Jelena Anti Stankovi Tatjana P. Stanojkovi 《Molecules (Basel, Switzerland)》2020,25(22)
Mahonia aquifolium and its secondary metabolites have been shown to have anticancer potential. We performed MTT, scratch, and colony formation assays; analyzed cell cycle phase distribution and doxorubicin uptake and retention with flow cytometry; and detected alterations in the expression of genes involved in the formation of cell–cell interactions and migration using quantitative real-time PCR following treatment of lung adenocarcinoma cells with doxorubicin, M. aquifolium extracts, or their combination. MTT assay results suggested strong synergistic effects of the combined treatments, and their application led to an increase in cell numbers in the subG1 phase of the cell cycle. Both extracts were shown to prolong doxorubicin retention time in cancer cells, while the application of doxorubicin/extract combination led to a decrease in MMP9 expression. Furthermore, cells treated with doxorubicin/extract combinations were shown to have lower migratory and colony formation potentials than untreated cells or cells treated with doxorubicin alone. The obtained results suggest that nontoxic M. aquifolium extracts can enhance the activity of doxorubicin, thus potentially allowing the application of lower doxorubicin doses in vivo, which may decrease its toxic effects in normal tissues. 相似文献
194.
Jelena G. Stamenković Olga P. Jovanović Jovana D. Ickovski Ivan R. Palić Gordana S. Stojanović 《Natural product research》2020,34(13):1947-1950
AbstractChemical composition of the headspace volatiles and essential oils isolated from different parts of Ferulago sylvatica was determined by GC and GC/MS analyses. The results showed that headspace volatiles obtained from the aerial parts and roots were similar regarding the number of identified compounds and main components. However, essential oils obtained from different plant organs showed significant differences in chemical composition. Myrcene was the most abundant component of the inflorescences and shoots volatiles, while α-pinene make up over 50% of the root volatiles. Only three components were identified in the root essential oil with 2,3,6-trimethyl benzaldehyde (92.7%) as the main component. In the shoots sample the terpenoid fractions represented 56% of the oil, unevenly distributed between monoterpenoids and sesquiterpenoids with germacrene D (32.5%) recognized as the main constituent. On the other hand, more than 94% of the inflorescences oils were monoterpenoids with myrcene as the most abundant contributor (29.2%). 相似文献
195.
Branislava M. Mitrović Svetlana N. Grdović Gordana S. Vitorović Duško P. Vitorović Gordana K. Pantelić Goran A. Grubić 《Isotopes in environmental and health studies》2014,50(4):538-545
Herbal teas are an important part of traditional medicine in Serbia. The objective of the present study was to determine the activity concentrations of 40K and 137Cs in herbal tea, using the gamma spectroscopy method. The samples were collected during the period 2011–2012 in three mountain regions in Western and Central Serbia. The activity concentrations of 40K and 137Cs were found to be in the range of 130–1160 and 0.7–124 Bq kg?1, respectively. The average annual effective dose equivalents from ingestion of 40K and 137Cs for an adult person consuming one cup of herbal tea daily were found to be 588.4–5250.2 nSv for 40K and 4.0–706.1 nSv for 137Cs. Our investigation showed that the herbal teas originating from Maljen, Zlatibor and Tara mountains are radiologically safe for human consumption. 相似文献
196.
Brian Scharf Cristina C. Clement Supansa Yodmuang Aleksandra M. Urbanska Sylvia O. Suadicani David Aphkhazava Mia M. Thi Giorgio Perino John A. Hardin Neil Cobelli Gordana Vunjak-Novakovic Laura Santambrogio 《Chemistry & biology》2013,20(7):922-934
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197.
Sleem F. Hmuda Nemanja P. Trišović Nataša V. Valentić Gordana S. Ušćumlić 《Journal of solution chemistry》2011,40(2):307-319
Two series of 3-(4-substituted benzyl)-5-ethyl-5-phenyl- and 3-(4-substituted benzyl)-5,5-diphenylhydantoins were synthesized
and their UV absorption spectra were recorded in the region 200–400 nm in selected solvents of different polarity. The effects
of solvent dipolarity/polarizability and solvent/solute hydrogen bonding interactions on the spectral shifts were analyzed
by means of the linear solvation energy relationship (LSER) methodology of Kamlet and Taft. The quantitative relationships
between hydrogen bonding interactions and the lipophilicity and blood-brain permeation of the studied compounds were discussed.
Satisfactory linear dependences were obtained for moderate electron-donating and electron-withdrawing substituents at the
benzyl moiety, while the strong electron-withdrawing substituent (NO2) significantly modifies the solvation characteristics of the molecule. The paper clearly demonstrates how the solvatochromic
comparison method may be applied to estimate the contributions of various modes of solvation to the pharmaceutically relevant
properties of these newly synthetized hydantoin derivatives. 相似文献
198.
The results of studying inhibitory effect of streptomycin on the modified Berthelot reaction were presented in this paper and a new kinetic method for determining streptomycin in pharmaceutical preparations and human urine was developed on the basis of the obtained results. The rates of catalytic and catalytic‐inhibitory reaction were monitored at 700 nm (t=25±0.1°C) using UV/vis spectrophotometer. By analyzing the spectra and experimental dependences of the catalytic and catalytic‐inhibitory reaction rates on the reactant concentrations, it was noticed that streptomycin attacked nitroprusside and hypochlorite causing the inhibition of the production of 2,2′‐dicarboxylindophenol. According to this effect, an analytical decrease for determination of urea by modified Berthelot reaction appeared in the presence of small amounts of streptomycin. Beer's law was obeyed in the interval of streptomycin sulfate concentration from 18.2 to 182 µg·mL?1. The detection limit calculated by two methods was obtained at 11.75 µg·mL?1 and 8.54 µg·mL?1. The relative standard deviation of 0.55%–8.83% and the recovery of 109.10% were determined. The obtained results were validated using the referent HPLC method. 相似文献
199.
Katarina avikin Jelena
ivkovi Teodora Jankovi Nada uji-Nikoli Gordana Zduni Neboja Menkovi Zorica Drini 《Molecules (Basel, Switzerland)》2021,26(13)
In this study we define the optimal conditions for ultrasound-assisted extraction of bioactive polyphenols from S. raeseri aerial parts using response surface methodology. The influence of ethanol concentration (10–90%), extraction temperature (20–80 °C), extraction time (10–60 min), and solid-to-solvent ratio (1:10–1:50) on total phenolic content as well as on content of individual flavonoids, and hypolaetin and isoscutellarein derivatives was studied. For the experimental design, a central composite design was chosen. In the obtained extracts, the following ranges of targeted compounds were detected: total phenol from 19.32 to 47.23 mg GAE/g dw, HYP from 1.05 to 11.46 mg/g dw, ISC 1 from 0.68 to 10.68 mg/g dw, and ISC 2 from 0.74 to 15.56 mg/g dw. The optimal extraction conditions were set as: ethanol concentration of 65%, extraction time of 50 min, extraction temperature of 63 °C, and solid-to-solvent ratio of 1:40. Contents of TP, HYP, ISC 1, and ISC 2 in optimal extracts were 47.11 mg GAE/g dw, 11.73 mg/g dw, 9.54 mg/g dw, and 15.40 mg/g dw, respectively. Experimentally set values were in good agreement with those predicted by the response surface methodology model, indicating suitability of the used model, as well as the success of response surface methodology in optimizing the conditions of the extraction. 相似文献
200.
Irini S. Reljin Milka L. Avramov-Ivi? Goran I. Plavec Gordana M. Bogdanovi? 《Physica A》2008,387(14):3563-3573
Multifractal (MF) approach was applied for the analysis of ultraviolet/visible (UV/VIS) spectra as an independent confirmation of the diagnostic efficacy of UV/VIS spectral analysis of intraperitoneal fluids, ascites, taken from patients with a known clinical diagnosis. Recently, it was reported that from UV/VIS spectra differentiation of malignant from benign ascites is possible. Here, it was shown that by using MF analysis of UV/VIS spectra, the objective classification of UV/VIS spectra is possible. The applicability of UV/VIS analysis and MF classification of spectra were evaluated on N=68 cases, of which M=64 and B=4 were clinically confirmed as malignant and benign, respectively. The overall diagnostic efficacy was 89.71% when using on-line analysis of UV/VIS spectra (61 out of 68 samples were positively recognized: 58 malignant and 3 benign), and even 95.59% by using off-line MF classsification (65 out of 68 samples were classified correctly: 63 malignant and 2 benign). It can be inferred that UV/VIS spectral analysis of ascites, combined with MF analysis, could be suggested as a successful and safe screening method in the evaluation of intraperitoneal fluids. 相似文献