Magdalena Piętka-Ottlik - Academia.edu (original) (raw)

Papers by Magdalena Piętka-Ottlik

Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2016

ChemInform, 2011

Compounds -[335 refs.]. -(MLOCHOWSKI, J.; PECZYNSKA-CZOCH, W.; PIETKA-OTTLIK, M.; WOJTOWICZ-MLOCH... more Compounds -[335 refs.]. -(MLOCHOWSKI, J.; PECZYNSKA-CZOCH, W.; PIETKA-OTTLIK, M.; WOJTOWICZ-MLOCHOWSKA, H.; Open Catal. J. 4 (2011) 54-82 ; Dep. Chem., Politec. Wroclawska, PL-50-370 Wroclaw, Pol.; Eng.) -Lindner 48-266

International Journal of Polymer Science, 2013

Hydrogel nanoparticles, referred to also as nanogels, are of special interest for medical and pha... more Hydrogel nanoparticles, referred to also as nanogels, are of special interest for medical and pharmaceutical applications. Due to small size in the range below the diameter of the capillaries, they are proposed as drug delivery carriers. The aim of the study was to estimate the influence of composition and reaction conditions during synthesis of poly-N-isopropyl acrylamide cross-linked by polyethylene glycol diacrylate on the purification rates of the polymer. Six types of thermosensitive nanogels were prepared by surfactant-free dispersion polymerization and assessed in terms of process yield, composition, and size at temperatures below and over volume phase temperature. During the diffusion of impurities, in the course of dialysis, assessed by the conductometric method, the remarkable influence of temperature and initiator concentration on the process was revealed. The release rates varied in the range between 9.63 ⋅ 10 −2 and 1.39 ⋅ 10 −1 h −1 in the first stage of the process, whereas in the second stage they were between 2.09 ⋅ 10 −2 and 6.28 ⋅ 10 −2 h −1 . The evaluated time to obtain acceptable purity of the preparation was estimated to be in the range of 18 days. More detailed research should be directed towards the influence of the structure of obtained material on the purification process.

Biological & pharmaceutical bulletin, 2012

Indoloquinoline alkaloids represent an important class of antimalarial, antibacterial and antivir... more Indoloquinoline alkaloids represent an important class of antimalarial, antibacterial and antiviral compounds. Indolo[2,3-b]quinolines are a family of DNA intercalators and inhibitors of topoisomerase II, synthetic analogs of neocryptolepine, an alkaloid traditionally used in African folk medicine. These cytotoxic substances are promising anticancer agents. Active representatives of indolo[2,3-b]quinolines affect model and natural membranes. The distinct structure and hydrophobicity of the compounds leads to marked differences in the disturbing effects on membrane organization and function. Our results also indicated a strong relationship between the presence of the chain and the Poct of the molecule as well as the capacity for incorporation into carboxyfluorescein-trapped liposomes in the 0.02-0.06 mM range. Moreover, a correlation between binding to neutral dimyristoylphosphatidylcholine (DMPC) or negative charged dimyristoylphosphatidylcholine:dimyristoylphosphatidylglycerol (DMP...

Phosphorus, Sulfur, and Silicon and the Related Elements, 2008

The seleno-organic compounds based on bis(2-aminophenyl) diselenide-1 are potential antiviral, an... more The seleno-organic compounds based on bis(2-aminophenyl) diselenide-1 are potential antiviral, antibacterial and antifungal agents. In this work, we reported synthesis of bis(2-aminophenyl) diselenide derivatives 2, 3 having amino acid and dipeptide moieties. This process was realized by acylation of amine groups in 1 with N-blocked amino acids, using the active esters method (with DCC and HOBT). After removing protective groups

Molecules, 2010

Various N-substituted benzisoselenazol-3(2H)-ones and their non-seleniumcontaining analogues have... more Various N-substituted benzisoselenazol-3(2H)-ones and their non-seleniumcontaining analogues have been synthesized and tested against selected viruses (HHV-1, EMCV and VSV) to determine the extent to which selenium plays a role in antiviral activity. The data presented here show that the presence of selenium is crucial for the antiviral properties of benzisoselenazol-3(2H)-ones since their isostructural analogues having different groups but lacking selenium either did not show any antiviral activity or their activity was substantially lower. The open-chain analogues of benzisoselenazol-3(2H)-ones-diselenides also exhibited high antiviral activity while selenides and disulfides were completely inactive towards model viruses.

Journal of Medicinal Chemistry, 2012

The syntheses of neocryptolepine derivatives containing an amino acid or a dipeptide at the C-9 p... more The syntheses of neocryptolepine derivatives containing an amino acid or a dipeptide at the C-9 position and their evaluation for antitumor activity in vitro and in vivo are reported. To establish the influence of an amino acid or a peptide on the physicochemical properties of 5H-indolo[2,3-b]quinoline (DiMIQ), lipophilic and hemolytic properties were investigated. Most of the compounds displayed a high antiproliferative activity in vitro and strongly inhibited growth of tumor in mice compared to cyclophosphamide. The attachment of the hydrophilic amino acid or the peptide to the hydrophobic DiMIQ increased its hydrophilic properties and decreased its hemolytic activity. The glycylglycine conjugate (7a) was the most promising derivative. It strongly inhibited the growth of the tumor in mice (at dose 50 mg kg(-1) day(-1) it inhibited the tumor growth by 46-63% on days 11-16 and by 29-43% on days 18-23) and significantly decreased hemolytic activity and lowered the in vivo toxicity compared to DiMIQ.

Journal of Enzyme Inhibition and Medicinal Chemistry, 2010

The plasma membrane H + -ATPase pump (Pma1p) has been proposed as a viable target for antifungal ... more The plasma membrane H + -ATPase pump (Pma1p) has been proposed as a viable target for antifungal drugs since this high capacity proton pump plays a critical role in the intracellular regulation of pH and in nutrient uptake of yeast and other fungi. In recent years, this and other laboratories have verified that the antifungal activity of 2-phenylbenzisoselenazol-3(2H)-one, an organoselenium compound commonly referred to as ebselen , stems, at least in part, from its inhibitory action on the fungal Pma1p. In the present study, the antifungal efficacy of 2-(3-pyridinyl)-benzisoselenazol-3(2H)-one (2) and 2-phenylbenzisoselenazol-3(2H)-one 1-oxide (3), two ebselen analogs, was evaluated using a strain of S. cerevisiae and compared against that of 1. In addition, the study also examined the inhibitory potential of these three compounds toward the Pma1p of S. cerevisiae. Based on mean IC 50 values, the antifungal potency was found to decrease in the order 3 > 1 > 2. However, in terms of inhibitory action on Pma1p, the potency decreased in the order 1 > 3 > 2. The magnitude of these activities appears to be correlated with the corresponding log P values, with compound 2 being the most hydrophilic and the least active of the three.

Journal of Biochemical and Molecular Toxicology, 2013

A series of test compounds were evaluated for an ability to reduce the toxicity of the nitrogen m... more A series of test compounds were evaluated for an ability to reduce the toxicity of the nitrogen mustard mechlorethamine (HN2) in vitro. The test compounds included resveratrol, pterostilbene, vitamin C, ebselen, ebselen diselenide, and ebselen-sulfur. Among them, ebselen demonstrated the highest degree of protection against HN2 toxicity. To this end, pretreatment of the cells with ebselen offered protection against the toxicant whereas no protection was observed when cells were first incubated with HN2 and then treated with ebselen. Significant increases in caspase 3 and caspase 9 activities were observed in response to HN2, and ebselen was found to reduce these effects. Taken together, the data presented here indicate that ebselen is an effective countermeasure to nitrogen mustard in vitro, which is worthy of future investigation in vivo.

Cutaneous and Ocular Toxicology, 2014

Sulfur mustard (SM) is a potent vesicant. The lack of an effective antidote makes SM a continued ... more Sulfur mustard (SM) is a potent vesicant. The lack of an effective antidote makes SM a continued threat to both military and civilian settings. A surrogate agent, namely mechlorethamine (HN2), was used here to mimic the toxicity of SM, and the main objective of this study was to demonstrate if selected organoselenium analogs could protect cultured A-431 skin cells from HN2 toxicity. Test compounds included ebselen (EB-1) and three related organoselenium analogs (EB-2, EB-3 and EB-4). In the absence of test compound, a reproducible and robust cell death was observed in the cells following incubation with HN2 (25 µM, 24 or 48 h) while cells treated with test compound alone (15, 30 or 60 µM) for similar periods of time were generally not affected. When incubated in the presence of both HN2 and test compound for 24 or 48 h, it was found that EB-1, EB-2, EB-3 and EB-4 could spare the cells from death, with the EB-4 compound being the most effective at reducing HN2 toxicity. Light microscopy confirmed these findings. The organoseleniums were also examined for their effects on reducing lipid peroxidation in the A-431 skin cells. Among the test compounds, EB-4 reduced lipid peroxidation by HN2 to the greatest extent. These studies, taken together, validate that the organoselenium antioxidants tested here may serve a purpose in the discovery of medical countermeasures to vesicants.

Chemosphere, 2012

h i g h l i g h t s " Mulifunctional cationic surfactants have been studied. " The toxicity and b... more h i g h l i g h t s " Mulifunctional cationic surfactants have been studied. " The toxicity and biodegradability of antielectrostatic agents have been investigated. " Surfactants were inactive against gram-negative bacteria and yeasts. " The aquatic toxicity depended on the alkyl chain length. " Biodegradation of few dicephalic surfactants reached over 60% within 28 d.

Archives of Industrial Hygiene and Toxicology, 2000

Vesicants are potent blistering agents. The prototype vesicant is sulphur mustard gas, fi rst use... more Vesicants are potent blistering agents. The prototype vesicant is sulphur mustard gas, fi rst used in World War I, which still has no effective antidote. We used a mustard gas surrogate 2-chloroethyl ethyl sulphide (CEES) to study the ability of resveratrol (RES) and pterostilbene (PTS), two well-established stilbene antioxidants, ebselen (EB-1), an organoselenium compound, and three EB-1 analogues (EB-2, EB-3, and EB-4) to reduce CEES toxicity in human epidermoid carcinoma cells (A-431). Following a 24-hour incubation of a toxic concentration of CEES (1000 μmol L -1 ), we used the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] test to analyse cell viability. Different concentrations of test antioxidants alone (15 μmol L -1 , 30 μmol L -1 or 60 μmol L -1 ) did not decrease cell viability. Treatment with CEES and test antioxidants for 24 h showed that only EB-1 and its analogues EB-2, EB-3, and EB-4 but not the stilbene compounds could rescue the cells from death. EB-1 and EB-4 were the most effective at reducing CEES cytotoxicity and did so in a concentration-dependent manner, while EB-2 and EB-3 demonstrated the least protective effect. In summary, the data described herein indicate that organoselenium antioxidants, especially EB-4, may prove useful as countermeasures to blistering agents.

ChemInform, 2009

New Organoselenium Compounds Active Against Pathogenic Bacteria, Fungi and Viruses. -A variety of... more New Organoselenium Compounds Active Against Pathogenic Bacteria, Fungi and Viruses. -A variety of N-substituted benzisoselenazol-3(2H)-ones (analogues of ebselen) are designed, synthesized and screened in antiviral, antibacterial and antifungal assays in vitro. Most of the compounds show strong fungicidal activity, high activity against viruses (HSV-1, EMCV) and gram-positive bacteria strains (S. aureus, S. simulans). However, their high cytotoxicity results in undesirable low chemotherapeutic indices. -(PIETKA-OTTLIK, M.; WOJTOWICZ-MLOCHOWSKA, H.; KOLODZIEJCZYK, K.; PIASECKI, E.; MLOCHOWSKI*, J.; Chem.