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Poly(vinyl alcohol)/graphene (PVA/Gr) nanocomposite was synthesized with the aim of developing a novel improved material. The PVA/Gr nanocomposite was characterized by UV-visible spectroscopy, cyclic voltammetry, Raman spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy analyses, and the interaction of PVA molecules with graphene was examined. Introduction of Gr led to improved mechanical and thermal properties of the PVA/Gr nanocomposite compared to pure PVA, as well as strong antibacterial activity against the bacterial strain Staphylococcus aureus. The PVA/Gr nanocomposite was non-cytotoxic against healthy peripheral blood mononuclear cells by MTT assay, indicating its high potential for biomedical applications. (C) 2015 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

The hydroxyapatite/graphene (HAP/Gr) composite was electrodeposited on Ti using the electrophoretic deposition process to obtain uniform bioactive coating with improved mechanical strength and favorable corrosion stability in simulated body fluid (SBF). Incorporation of Gr was verified by Raman spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray photoelectron analysis. The HAP/Gr composite coating exhibited reduced surface cracks, nearly double the hardness, and elastic modulus increased by almost 50% compared to pure HAP coating, as estimated by a nanoindentation test. The bioactive HAP/Gr composite coating provided a newly formed apatite layer in SBF with enhanced corrosion stability, as evidenced by electrochemical impedance spectroscopy. The thermal stability of the HAP/Gr coating was improved in comparison to the pure HAP coating, and the Ca/P ratio was closer to the stoichiometric value. No antibacterial activity against Staphylococcus aureus or Escherichia coli could be verified. The HAP/Gr composite coating was classified as non-cytotoxic when tested against healthy peripheral blood mononuclear cells (PBMC).

The in vitro cytotoxic activity of previously synthesized steroid dimers with different spacer group (sulfide, trithiolane ring or phosphorotrithioate) and the substituent at C-17 position was tested for their possible effects against following human tumor cell lines: cervical adenocarcinoma (HeLa), chronic myelogenous leukemia (K562) and two human breast cancer cell lines (MDA-MB-361 and MDA-MB-453). These compounds, applied at micromolar concentrations, exhibited cytotoxic activity of different intensity (compared with cisplatin as a control), modality and selectivity in these malignant cell lines. The best activity against all four cell cancer lines was exhibited by dimer-sulfides. All screened compounds exerted concentration-dependent cytotoxic activity against leukemia K562 cells. The compounds which exerted the most pronounced cytotoxic action exhibited notably higher cytotoxic activities against K562, HeLa and MDA-MB-453 cells in comparison to resting and PHA-stimulated PBMC, pointing to a significant selectivity in their antitumor actions. Examination of the mechanisms of cytotoxicity on leukemia K562 cells revealed pro-apoptotic action of each of the investigated compounds applied at concentrations 2IC(50). The most prominent pro-apoptotic action was exhibited by dimer-sulfide of cholest-4-en-3-one. Furthermore, almost all of the tested compounds at IC50 concentrations induced G1 phase cell cycle arrest in K562 cells. Antimicrobial activity against Gram-positive, Gram-negative bacteria and fungal cells, and toxicity to brine shrimp Artemia sauna, were evaluated. There was no antibacterial activity. The best antifungal activity was exhibited against Saccharomyces cerevisiae by dimers linked with trithiolane ring, indicating a selective activity of investigated compounds. (C) 2014 Elsevier Ltd. All rights reserved.

Helichrysum zivojinii Cernjavski & Soska is an endemic plant species that grows in the National Park Galicica in Macedonia. Five extracts were isolated as fractions from the aerial parts of the plant: a n-hexane extract (1), a dichloromethane extract (2), an ethyl-acetate extract (3), a n-butanol extract (4) and a methanol extract (5). A dose-dependent cytotoxic activity of the extracts on MDA-MB-231 and EA.hy926 cells was observed. Extracts exhibited more pronounced cytotoxic actions on MDA-MB-231 cells than on EA.hy926 cells. The n-hexane extract (1), at a non-toxic concentration, exhibited an inhibitory effect on the migration as well the invasiveness of MDA-MB-231 cells. The dichloromethane extract (2), at a non-toxic concentration, demonstrated inhibition of MDA-MB-231 cells invasion. Each of the five extracts applied at non-toxic concentrations inhibited migration of EA.hy926 cells. The prominent inhibitory effect of the n-hexane extract on EA.hy926 cells migration was associated with a notable anti-angiogenic action of this extract. The other four tested extracts demonstrated mild anti-angiogenic activity. Our data highlight the prominent anticancer potential of n-hexane (1) and dichloromethane (2) extracts, which could be attributed to their very pronounced and selective cytotoxic activities as well as their anti-invasive and anti-angiogenic properties.

Six novel gold(III) complexes containing O,O'-dialkyl-(S,S)-ethylenediamine-N,N'-di-2-(3-cyclohexyl)propanoate ([AuCl2{(S,S)-R(2)eddch}]PF6, R = Me, Et, n-Pr, n-Bu, i-Bu, i-Am; 1-6, respectively) were synthesized and characterized by elemental analysis, UV/Visible, IR and NMR spectroscopy, mass spectrometry and differential pulse voltammetry. Density functional theory (DFT) calculations confirmed that diastereoisomer with the N,N' atoms configured (S,S) was the most stable. In vitro antiproliferative activity was determined against human cervix adenocarcinoma HeLa and human myelogenous leukemia K562 tumor cell lines, as well as against rested and stimulated normal immunocompetent human peripheral blood mononuclear cells (PBMC) using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Complex 6 expressed the highest activity against K562 cells (IC50 = 3.8 +/- 0.5 mu M). Apoptosis, seen as condensation of HeLa cell nuclei was the mode of cell death induced by complexes 2-6. Complexes 3-6 induced death of K562 cells inhibiting cell entry in mitosis.

Background: The aim of this research was to determine the intensity and mechanisms of the cytotoxic actions of five extracts isolated from the endemic plant species Helichrysum zivojinii Cernjavski & Soska (family Asteraceae) against specific cancer cell lines. In order to evaluate the sensitivity of normal immunocompetent cells implicated in the antitumor immune response, the cytotoxicity of extracts was also tested against healthy peripheral blood mononuclear cells (PBMC). Methods: The aerial parts of the plants were air-dried, powdered, and successively extracted with solvents of increasing polarity to obtain hexane, dichloromethane, ethyl-acetate, n-butanol and methanol extracts. The cytotoxic activities of the extracts against human cervix adenocarcinoma HeLa, human melanoma Fem-x, human myelogenous leukemia K562, human breast adenocarcinoma MDA-MB-361 cells and PBMC were evaluated by the MTT test. The mode of HeLa cell death was investigated by morphological analysis. Changes in the cell cycle of HeLa cells treated with the extracts were analyzed by flow cytometry. The apoptotic mechanisms induced by the tested extracts were determined using specific caspase inhibitors. Results: The investigated Helichrysum zivojinii extracts exerted selective dose-dependent cytotoxic actions against selected cancer cell lines and healthy immunocompetent PBMC stimulated to proliferate, while the cytotoxic actions exerted on unstimulated PBMC were less pronounced. The tested extracts exhibited considerably stronger cytotoxic activities towards HeLa, Fem-x and K562 cells in comparison to resting and stimulated PBMC. It is worth noting that the cytotoxicity of the extracts was weaker against unstimulated PBMC in comparison to stimulated PBMC. Furthermore, each of the five extracts induced apoptosis in HeLa cells, through the activation of both intrinsic and extrinsic signaling pathways. Conclusion: Extracts obtained from the endemic plant Helichrysum zivojinii may represent an im

Background: Dipeptidyl peptidase IV, a multifunctional serine protease, is implicated in regulation of malignant transformation, promotion and further progression of cancer, exerting tumor-suppressing or even completely opposite - tumor-promoting activities. The aim of present research was to determine the serum DPPIV activity, as well as the percentages of CD26+ lymphocytes, CD26+ overall white blood cells and the mean fluorescence intensity of CD26 expression on lymphocytes in patients with melanoma, people with vitiligo and in healthy controls. Methods: The activity of DPPIV in serum was determined by colorimetric test. Expression of DPPIV (as CD26) on immunocompetent peripheral white blood cells was done using flow cytometry analysis. Results: Data from our study show for the first time statistically significant decrease: in the serum DPPIV activity, in the percentage of CD26+ overall white blood cells and in the percentage of lymphocytes in patients with melanoma in comparison to healthy control people. In addition, significantly lower serum DPPIV activity was found in the group of patients with melanoma in relation to people with vitiligo too. Conclusion: This study indicates the need for exploring the cause and the importance of the disturbances in the serum DPPIV activity and in the CD26 expression on immunocompetent cells in complex molecular mechanisms underlying the development and progression of melanoma

A series of new raft-unsaturated conjugated ketones containing ferrocenyl pyrazole unit were synthesized and fully characterized by IR and NMR spectroscopy. Electrochemical characterization of subject compounds was performed by means of cyclic voltametry. The in vitro cytotoxic activity of all the synthesized compounds was studied against cervix adenocarcinoma HeLa, melanoma Fem-x and myelogenous leukemia K562 cell lines by the MIT method. Derivative II containing 3-pyridyl moiety exhibited a better cytotoxic activity in the cell growth inhibition of 1(562 cell lines in comparison with cisplatin as a reference compound. (C) 2009 Elsevier Inc. All rights reserved.

Nine alkyl(aryl)thio derivatives of the marine sesquiterpene quinone avarone were synthesized by nucleophilic addition of thiols or thiophenol to avarone. In most cases only one regioisomer was obtained. Their cytotoxic activities, brine shrimp lethality and antibacterial activity were evaluated, as well as those of some previously synthesized avarone derivatives. Anti-HIV activity of two derivatives was tested. Electrochemical properties were determined for all the derivatives in Order to obtain more accurate information on structure-activity relationships. Most derivatives showed cytotoxic activity against tumor cell lines, with IC(50) values less than 10 mu M for some of them, in particular those with electron-donating substituents. The most active Compound was 4'-(methylamino)avarone, with IC(50) value of 2.4 mu M to melanoma Fem-X cells, and no cytotoxicity to normal lymphocytes. (C) 2009 Elsevier Masson SAS. All Fights reserved.

An alignment-free 3D QSAR study on antiproliferative activity of the thirty-three 1,2,4,5-tetraoxane derivatives toward two human dedifferentiated cell lines was reported. GRIND methodology, where descriptors are derived from GRID molecular interaction fields (MIF), were used It was found that pharmacophoric pattern attributed to the most potent derivatives Include amido NH of the primary or secondary amide, and the acetoxy fragments at positions 7 and 12 of steroid core which are, along with the tetraoxane ring, common for all studied compounds. Independently, simple multiple regression model obtained by using the whole-molecular properties, confirmed that the hydrophobicity and the H-bond donor properties are the main parameters influencing potency of compounds toward human cervix carcinoma (HeLa) and human malignant melanoma (FemX) cell lines Corollary, similar structural motifs are found to be Important for the potency toward both examined cell lines. (C) 2010 Elsevier Masson SAS. All rights reserved.

A simple approach to a stable steroidal estrone derived A.B-spiro system is reported. Treatment of estrone derived A-ring diepoxyalcohol with the Ac(2)O-TMSOTf system at the ambient temperature led to acetylation, while at the reflux temperature the acid-catalysed rearrangement took place affording the spiro-compound. Results of extensive in vitro and in vivo anticancer tests on the diepoxide, as well as preliminary data on the anti proliferative activity of the spiro-product against three cancer cell lines, are also presented. (C) 2009 Elsevier Inc. All rights reserved.

A series of new N-[(3-ferrocenyl-1-phenylpyrazol-4-yl)methyl] alpha-amino acids were prepared and characterized by a range of spectroscopic techniques and cyclic voltammetry. The in vitro antitumor activity of all synthesized compounds was investigated against cervix adenocarcinoma HeLa, melanoma Fem-x and myelogenous leukemia K562 cell lines using the MTT method. Tryptophan derivative 11 exhibited the highest cytotoxic activity in the cell growth inhibition of all three types of cell lines. (C) 2009 Elsevier B.V. All rights reserved.

Ruthenium(III) complexes formulated as K2[Ru(sar)Cl4]H2O and K[Ru(dmgly)2Cl2]3H2O containing bidentate chelates N-methylglycine (sarcosine, sar) or N,N-dimethylglycine (dmgly) as well as K[Ru(pdda)Cl2]2.5H2O complex with tetradentate 1,3-propylenediamine-N,N'-diacetato were synthesized. The complexes were obtained by direct reaction of ruthenium(III) chloride with the corresponding bidentate or tetradentate ligand followed by addition of a base (KOH). These new complexes were characterized by elemental analysis, IR and electronic absorption spectroscopy. To assess selectivity in the antitumor action of these complexes, their antiproliferative activities against human adenocarcinoma HeLa cells, human myelogenous leukemia K562 cells, human breast carcinoma MDA-MB-361 and MDA-MB-453 cells and normal immunocompetent PBM cells were determined.

New R(2)eddip-type esters (R = cyclopentyl, L3 center dot 2HCl 1.5H(2)O; cyclohexyl, L4 center dot 2HCl center dot H2O) and corresponding palladium(II) complexes, [PdCl(2)L3] (3) and [PdCl2L4]center dot H2O (4), as well as [PdCl2L2] (2: L2 diisobutyl ester of eddip) were synthesized and characterized by IR, H-1 and C-13 NMR spectroscopies and elemental analysis. The crystal structure of L3 center dot 2HCl center dot 2CHCl(3) was resolved and is given herein. The NMR spectroscopy confirmed the presence of two isomers (from three possible) for each palladium(II) complex. DFT calculations support the formation of two diastereoisomers. In addition, antitumoral investigations were performed and these investigations also included the diisopropyl ester of eddip (L1) and corresponding palladium(II) complex, [PdCl(2)L1] (1). In vitro anti proliferative activity was determined against several tumor cell lines HeLa, Fem-x, K562 and rested and stimulated normal immunocompetent cells (human peripheral blood mononuclear cells -PBMCs) using MTT test. (C) 2009 Elsevier Masson SAS. All rights reserved.

In this study we investigated the antiproliferative activity of six mixed steroidal tetraoxanes against various tumor cell lines, the toxicity against normal peripheral blood mononuclear cells (PBMC), and the mode of HeLa cell death induced by these compounds. Investigated tetraoxanes exerted a dose dependent antiproliferative action at micromolar concentrations toward target tumor cell lines. Treatment of HeLa cells for 24 h with all tetraoxanes induced apoptosis, as confirmed by morphological analysis and by the appearance of a typical ladder pattern in the DNA fragmentation assay.

Two new p-cymene ruthenium(II) complexes containing as additional ligands N-methylpiperazine ([(eta(6)-p-cymene)RuCl2(CH3NH(CH2)(4)NH)]PF6, complex 1) or vitamin K-3-thiosemicarbazone ([(eta(6)-p-cymene)RuCl2(K(3)tsc)], complex 2) were synthesized starting from [(eta(6)-p-cymene)(2)RuCl2](2) and the corresponding ligand. The complexes were characterized by elemental analysis, IR, electronic absorption and NMR spectroscopy. The X-ray crystal structure determination of complex 1 revealed "piano-stool" geometry. The differences in the cytotoxic activity of the two complexes are discussed in terms of the ligand present., Sintetisana su dva nova p-cimen-rutenijum(II) kompleksa koji sadrže kao dodatne ligande N-metilpiperazin ([(h6-p-cimen)RuCl2(CH3NH(CH2)4NH)]PF6, kompleks 1) i vitamin K3-tiosemikarbazon ([(h6-p-cimen)RuCl2(K3tsc)], kompleks 2). Oba nova kompleksa dobijena su polazeći od [(h6-p-cimen)2RuCl2]2 kompleksa i odgovarajućeg liganda. Kompleksi su okarakterisani elementalnom analizom, IC, elektronsko-apsorpcionom i NMR spektroskopijom. Rendgeno-strukturna analiza kompleksa 1 pokazala je “piano-stool” geometriju. U zavisnosti od prisutnog liganda diskutovana je razlika u citotoksičnoj aktivnosti ova dva dobijena kompleksa.