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Polylactide (PLA) stereocomplexes (SCs) were prepared from low molecular weight PLLA and PDLA with terminal carboxyl groups in the presence and in the absence of calcium oxide being a donor of metal ions. Only the stereocomplexation performed in the presence of metal ions causing PLA macromolecules preorganization resulted in the SC formation in a form of spherical microparticles (microspheres). Hydrolyses of microspheres containing CaO and the SC without CaO were performed in a phosphate buffer pH = 7.4 at temperatures 37 and 50 °C. The rate of hydrolytic degradation of SCs was studied and compared to find the effect of the metal ions presence. The results of the hydrolysis were analyzed by the observation of polymer samples using scanning electron microscopy and infrared spectroscopy, also by differential scanning calorimetry measurements.

Medium molecular weight polylactides (PLAs) with different end groups were synthesized and analyzed by matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry. Four types of end groups were introduced as head group using appropriate initiators: cationic group [ionic liquid group (IL-PLA-OH)], easily ionizable groups [aminopyridine group (AmPy-PLA-OH) and terpyridine group (TerPy-PLA-OH)], and neutral group [butoxy group (Bu-PLA-OH)]. MALDI-TOF spectra were recorded with various cationizing agents (Li+, Na+, and K+ salts). Different modes of ionization were observed depending on the nature of end group. These various modes of ionization lead to different ionization efficiencies, which affect signal intensity. Moreover, analysis of 1/1 mixtures showed that in spectra of mixtures of IL-PLA-OH with either AmPy-PLA-OH or Bu-PLA-OH, only the signals of IL-PLA-OH were detected, while in the spectrum of AmPy-PLA-OH with Bu-PLA-OH, the former gave signals with intensity about one order of magnitude higher than the latter. Such discrimination resulting from different modes and efficiencies of ionization of macromolecules containing structurally different end groups may lead to erroneous conclusions.

Linear and star-shaped polymers have been synthesized by the controlled ring-opening (ROP) polymerization of l - and d -lactide using 1-methyl-2-hydroxymethyl-3-butylimidazolium tetrafluoroborate and dipentaerythritol as initiators, respectively. To introduce carboxylic end-groups onto the star-shaped polylactides, the reaction of –OH end-groups with succinic anhydride was employed. Afterwards, the starting and modified polylactides were used for the preparation of star-shaped and star-shaped/linear stereocomplexes in 1,4-dioxane and tetrahydrofuran (THF). In these solvents, the stereocomplexes spontaneously precipitated. Star-shaped stereocomplexes with hydroxyl end-groups formed microspheres with diameters ranging from 1 to 4 μm (depending on the initial concentration of sc-PLA components) following precipitation from THF. However, the combined effect of the nature of the end-groups and PLA architecture causes the formation of uniform stereocomplex nanoparticles (∼400 nm) in 1,4-dioxane from the combination of star-shaped PLA functionalized with carboxylic end-groups and linear PLA with ionic liquid end-groups. Microscopic analysis showed that nanometre-sized grains of stereocomplexes (∼30 nm) aggregated to form larger stereocomplex nanoparticles. It was observed that the combination of three factors, i.e., the end-group interactions, architecture of the enantiomeric components, and basicity of the solvent in which the stereocomplexes are prepared, influences the properties and morphology of the final stereocomplex-based materials.

The polymerization of lactide performed in the presence of primary amines and a protic acid was reinvestigated. The polymerization products obtained at different [protic acid]/[amine] ratios were analyzed by 1 H NMR, GPC and MALDI TOF assays. Kinetic experiments proved that the addition of the acid resulted in an increase in the polymerization rate. It was shown that the amine is an efficient initiator in this process and that the protic acid is a cationic catalyst. The possibility of using different amino acids as the initiators of the acid-catalyzed lactide polymerization was also indicated.

Incubation of the Colorado potato beetle aggregation pheromone, (S)-1,3-dihydroxy-3,7-dimethyl-6-octen-2-one, with antennal or leg extracts from this beetle gave 6-methyl-5-hepten-2-one as the major product. This ketone was used as a substrate in a stereoselective synthesis of the pheromone. It was attached to the butanediacetal of glycolic acid with good stereoselectivity and the desired isomer was further enriched by purification of the product of this reaction on silica gel.

Polylactides with one or more carboxyl groups at one chain end were synthesized by cationic polymerization according to activated monomer mechanism and by application of “thiol-yne” click chemistry for subsequent functionalization. End groups of such obtained polylactides were converted into ionic groups by neutralization of polymer solutions with metal oxides, mainly calcium oxide, and the aggregation of individual stereoisomers as well as that of the mixture of poly(l-lactide) (PLLA) and poly(d-lactide) (PDLA) was investigated. The extent and progress of the aggregation was followed by viscosity measurements, and aggregated polymers in the solid state were examined by SEM and DSC. Solution viscosity increase was observed upon the aggregation of individual PLA stereoisomers, whereas PLA stereocomplex precipitation occurred in the case of the aggregation of PLLA/PDLA/metal oxide mixture.

In this study, new electrolytes for Li-ion batteries in the form of lithium salt solutions in room temperature imidazolium ionic liquids (RTIL) are reported. The ionic liquids applied, for higher reduction potential stability, were substituted at position C2 with oligooxyethylene groups of various length ([Im nEO]+X−; where: n = 0, 3, 7, 20 and X = Cl, BF4, N(CF3SO2)2). It was found that they are good solvents for lithium salts (LiBF4, LiN(CF3SO2)2, {[CH3(OCH2CH2)3O]3BC4H9}Li) forming liquid solutions of low glass transition temperature (Tg in the −70 to −40 °C range). Ionic conductivity depends on the length of oxyethylene substituent in Im nEO and on the concentration of the salt applied, for 10 mol%, σRT is of the order of 10−4 S cm−1. On the basis of polarization measurements by the variable-current method, the proportion of lithium cations in electric charge transfer (t+) has been determined. The values obtained (typical for ionic liquids) are low and depend on n and lithium salt concentration but do not exceed a dozen or so percent.

SR-A/CD204 and CD36 are major receptors responsible for oxidized lipoproteins uptake by macrophages in atherosclerotic plaques. Both receptors also share the role as receptors for different pathogens, but studies on their signaling have been hampered by the lack of selective ligands. We report that, upon specific ligation by Ab, SR-A does not induce cytokine production, but mediates inhibition of LPS-stimulated production of IL-6 and IL-12/23p40, enhancement of IL-10 release, and has no effect on TNF-α and RANTES production in murine macrophages. In contrast, anti-CD36 Ab alone stimulated production of all these cytokines, with IL-10 production being exceptionally high. Effects of anti-CD36 Ab, except of IL-10 production, were mediated by CD14 and TLR2, whereas those of SR-A ligation by heterotrimeric Gi/o proteins and by phosphatidylinositol 3-kinases. Surprisingly, we found that LPS uptake by macrophages was mediated in part by CD36 cooperating with CD14, whereas SR-A was not involved in this process. Finely, during in vitro Ag presentation to naïve CD4+ lymphocytes, pre-incubation of macrophages with anti-CD36 Ab enhanced IFN-γ production in the co-culture, but exerted the opposite effect under conditions enabling IL-10 accumulation. In contrast, anti-SR-A Ab was ineffective alone, but reversed the Th1-polarizing effect of LPS.

In this paper, the combined effect of the infl uence of polylactide (PLA) end-group nature and PLA architecture on the morphology of stereocomplexes formed during precipitation from organic solvent is investigated. Stereocomplexation of star-shaped poly( L -lactide) and linear poly( D -lactide) functionalized with imidazolium ionic liquid end groups in 1,4-dioxane leads to the formation of uniform microspheres, which are able to crystallize in the form of colloidal crystals. Microscopic scanning electron microscopy (SEM) and atomic force microscopy (AFM) analysis show the hierarchical structure of the system starting from the nanometrical grains composed of few stereocomplex macromolecules that aggregate in uniform microspheres fi nally forming colloidal crystals of microspheres.

Bionanotechnology has emerged up as integration between biotechnology and nanotechnology for developing biosynthetic and environmental-friendly technology for synthesis of nanomaterials. Different types of nanomaterials like copper, zinc, titanium, magnesium, gold, and silver have applied in the various industries but silver nanoparticles have proved to be most effective against bacteria, viruses and eukaryotic microorganisms. The antimicrobial property of silver nanoparticles are widely known. Due to strong antibacterial property silver nanoparticles are used, e.g. in clothing, food industry, sunscreens, cosmetics and many household and environmental appliances. The aim of the study was to compare the effect of silver nanoparticles (AgNPs) synthesized biologically and chemically on the biofilm formation. The biofilm was formed by the bacteria isolated from the water supply network. The commonly used crystal violet assay (CV) was applied for biofilm analysis. In this study effect of biologically synthesized Ag-NPs on the biofilm formation was evaluated.

Among metal nanoparticles, silver nanoparticles are a widely used in various life sectors such as in biomedical applications, air and water purification, food production, cosmetics, garments and in various household products. There are several methods for production of silver nanoparticles. Generally, silver nanoparticles can be prepared by chemical methods such as chemical reduction and electrochemical techniques, physical methods, and biological methods such as the use of microorganisms. The biological route of synthesis provides a great diversity in choice for its raw materials such as bacteria, algae, fungi and plants. The aim of the study was to evaluate the tetrazolium/formazan test as a method to determine antibiofilm activity of biological synthetized silver nanoparticles. In this study Bacillus subtilis grown on brewery effluent and produced biosurfactant was used for silver nanoparticles (Ag-NPs) synthesis. The culture supernatants were used in synthesis of Ag-NPs. The formation of nanoparticles accompanied by colour changes of the used reaction system was confirmed by UV-vis spectroscopy. The bacteria isolated from the biofilm of water supply system were used in the evaluation of the antibiofilm activity of biologically synthetized Ag-NPs. To compare the results the commonly used crystal violet assay (CV) for biofilm analysis was applied.

An equimolar mixture of fluoroborate salts: LiBF4 and lithium difluoro(oxalate)borate LiBF2(C2O4) (MIX-LiFBs) was obtained from a simple one-step reaction of lithium oxalate and boron fluoride. Voltamperommetry shows that the salt obtained is stable in the potential range of 4.9 V. Impedance measurements of liquid electrolytes involving imidazolium ionic liquid and aliphatic carbonates have been carried out, which show the highest ionic conductivity of the order of 10−3 S cm−1 (and low activation energy of 0.14 eV) when using carbonates as the solvent. The mixture of fluoroborate salts MIX-LiFBs used as a component of solid polymer electrolytes provides much higher ionic conductivity values at high salt concentrations in “polymer-in-salt systems”. The conductivity of solid polymer electrolytes was considerably increased by adding a low-molecular-weight organic plasticizer.

There has been a recent upsurge in interest in use of ionic liquids as reaction media for various chemical processes. Until recently, ionic liquids were considered as highly polar solvents. Our earlier investigation indicated that cationic polymerization of styrene initiated by aryl (alkyl) chlorides in ionic liquids may proceed even in the absence of coinitiator (Lewis acid). Polymerization, however, did not conform to controlled polymerization scheme. More recently, it has been claimed that ionic liquids are not as polar as it was previously assumed. Independently, high solubility of sulfur dioxide in ionic liquids was noticed. As sulfur dioxide displays a high ionizing power toward organic halides, we applied ionic liquid/sulfur dioxide mixture as a solvent in cationic polymerization of styrene initiated by aryl (alkyl) chlorides. Results show that in this reaction medium ionization of the C―Cl bond is facilitated, and the contribution of chain transfer reaction can be reduced as compared with polymerization in ionic liquid alone. Ionization of the C―Cl bond, however, is still not sufficiently fast to ensure conditions of controlled polymerization.

It has been observed by us earlier that imidazolium ionic liquids ([bmim][BF4] react with paraformaldehyde giving in nearly quantitative yield imidazolium ionic liquids substituted at 2-position with hydroxymethyl group ([bhmim][BF4]). In this article, we describe the application of those ionic liquids (after converting hydroxyl group into alkoxide anion by reaction with sodium hydride) as initiators for anionic polymerization of ethylene oxide (EO). Up to DPn ∼ 30 polymerization proceeds without side reactions, and the product is exclusively low-molecular-weight polyoxyethylene containing imidazolium head group (POE-IL) with DPn equal to [EO]/[bhmim] ratio. By increasing [EO]/[bhmim] ratio further, side reaction start to interfere, and macromolecules that does not contain imidazolium head groups are also formed, as evidenced by analysis of MALDI TOF spectra. Blending of POE-IL with high-molecular-weight POE leads to significant reduction of crystallinity of POE. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6961–6968, 2008

Synthesis of block-graft copolymers, namely poly(epichlorohydrin-b-styrene)-g-poly(methyl methacrylate) (PECH-b-St)-g-PMMA) by combination of Activated Monomer (AM), Nitroxide Mediated Polymerization (NMP) and Atom Transfer Radical Polymerization (ATRP) methods was described. For this purpose, first epichlorohydrin (ECH) was polymerized by using BF3THF complex in the presence of 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyl-1-oxy (HTEMPO) via AM mechanism. The resulting stable radical terminated polymer was subsequently used as a counter radical in the NMP of styrene (St) initiated by benzoyl peroxide to yield block copolymers of ECH and St. Finally, the ATRP of methyl methacrylate (MMA) by using chloromethyl groups of the PECH segment as initiating sites resulted in the formation of (PECH-b-St)-g-PMMA). The structures of the intermediate polymers at various stages were characterized by 1H-NMR spectral investigations. The thermal behavior and surface morphology of the copolymers were also investigated by DSC and AFM measurements.

In this work we studied interactions between bacterial antigens and receptors on the surface of macrophages using atomic force microscopy (AFM). We used two bacterial cell wall components: lipopolysaccharide (LPS) derived from gram-negative Escherichia coli and exopolysaccharide (EPS) derived from gram-positive Lactobacillus rhamnosus. Interactions between these bacterial antigens and immune cell receptors were studied in peritoneal macrophages derived from two strains of mice, CBA and C3H/J, in which the Toll-like receptor 4 (TLR4) is genetically disabled. We collected 500 force-distance curves for LPS-activated cells using an EPS-covered AFM tip, and for EPS-activated cells using an LPS-covered AFM tip. Nonactivated cells were tested as reference cells. The results show that LPS-primed macrophages decrease their ability to bind EPS. Surprisingly, EPS-activated macrophages maintain or even increase their ability to bind LPS. This may suggest that in vivo commensal enteric bacteria, such as lactobacilli, will enhance the defense potential of local macrophages against pathogens expressing LPS.

Cationic ring-opening polymerization of 3-ethyl-3-hydroxymethyloxetane (EOX) in a neutral ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate, [bmim][BF 4 ]) leading to a multihydroxyl, branched polyether proceeds readily to nearly quantitative conversion. Because of the relatively high polarity of ionic liquids, intermolecular hydrogen bonding leading to the formation of aggregates is reduced considerably. On the other band, intramolecular hydrogen bonding facilitating intramolecular chain transfer is not significantly affected and the molecular weights of polymers are in the same range as those obtained in bulk polymerization or polymerization in organic solvents.

The cationic polymerization of styrene in a neutral ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate, with a 1-phenetyl chloride/TiCl 4 initiating system is reported. The polymerization proceeds to a high conversion, but an analysis of the matrix-assisted laser desorption/ionization time-of-flight spectra of the polymers indicates that chain transfer is significant, leading to a lack of control over the molecular weight and molecular weight distribution.

Application of ionic liquids (organic salts that are liquid at ambient temperatures) as solvents for atom transfer radical polymerization (ATRP) of acrylic monomers is described. Ionic liquids dissolve several inorganic and organic compounds, are highly polar and non-volatile. It has been shown that their application as solvents in ATRP of acrylates allows the reduction of side-reactions when compared against bulk polymerizations. When chiral ionic liquid was used as a solvent a small but clear effect on polymer tacticity was observed.

Taurine chloramine (TauCl), a product of neutrophil myeloperoxidase - halide system, formed by a reaction of taurine with HOCl, is known as an anti-microbial and anti-inflammatory long-lived oxidant. We previously reported that TauCl inhibits in vitro the production of proinflammatory cytokines (IL-6, IL-8) by RA synoviocytes. Therefore we performed this study to investigate the effect of TauCl treatment on the development of collagen-induced arthritis (CIA) in DBA1/J mice. Early administration of TauCl (after primary immunization) resulted in the delay of the onset of CIA, but had no effect on severity of arthritis. TauCl, given daily for 21 days after booster immunization, did not reduce the symptoms of arthritis in those mice, which already developed CIA, but significantly diminished incidence of the disease (55% vs. 90% of placebo mice). The mechanism of this effect is unknown. This is the first in vivo study suggesting that TauCl may be used for immune intervention in chronic inflammatory diseases.

The reaction between diepoxides and difunctional acids of phosphorus was studied as a potential route to linear polyesters of phosphoric acid. The reaction between diepoxide and P-OH groups in H3PO4 and related acids leads to linear phosphates, but cyclic phosphates are also formed as side products. The formation of such unreactive groups terminates polyaddition. However, cyclization is practically eliminated when the epoxide ring is fused to another ring, such as in cyclohexene oxide. A commercially available diepoxide containing two cyclohexene oxide moieties, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate (ERL), was, therefore, used for polyaddition studies. Indeed, in the polyaddition of ERL with ethylphosphoric acid, high molecular weight (number-average molecular weight up to 10^4) linear polyphosphates were obtained.

The photoinitiated free-radical polymerization of methyl methacrylate (MMA) and the radical-promoted cationic polymerization of cyclohexene oxide (CHO) in the presence of low-molecular-weight polyepichlorohydrin terminated with groups containing benzoin derivatives were studied. Benzoin-terminated polyepichlorohydrin was prepared by Activated Monomer (AM) polymerization. Upon photolysis. polymer-bound alkoxy benzyl radicals were generated, initiating the radical polymerization of MMA. In the case of radical-promoted cationic polymerization of CHO, the cationic initiating species were formed by the oxidation of photochemically generated polymeric radicals by N-ethoxy-2-methylpyridinium hexafluorophosphate. Die photoinitiierte radikalische Polymerisation von Methylmethacrylat (MMA) und die radikalisch eingeleitete kationische Polymerisation von Cyclohexenoxid (CHO), jeweils in Gegenwart von niedermolekularem Polyepichlorhydrin mit Benzoinderivaten als Endgruppen, werden beschrieben. Polyepichlorhydrin mit Benzoin-Endgruppen wurde durch eine „aktivierte Monomer” (AM)-Polymerisation hergestellt. Durch Photolyse wurden polymergebundene Alkoxybenzyl-Radikale erzeugt, die die radikalische Polymerisation von MMA initiieren. Bei der radikalisch eingeleiteten kationischen Polymerisation von CHO wurden die Kationen aus photochemisch erzeugten Polymerradikalen durch Oxidation mit N-Ethoxy-2-methylpyridinium-hexafluorphosphat gebildet.

Poly(oxyethylene)s with number-average degrees of polymerization (DP n ) ranging from 6 to 80, terminated at both ends with phosphonium ion end groups (diionic poly-EO), have been prepared and characterized as described in the preceding paper. Viscosities of diionic poly-EO were measured, both in solution and in bulk. In chloroform solution, at low concentration (< 1 g/100 mL), the viscosity of diionic poly-EO was lower than the viscosity of nonionic (terminated with HO-groups) poly-EO of the same DP n . At higher concentrations, the viscosity of diionic poly-EO exceeded that of nonionic poly-EO and increased sharply with increasing concentration. At the constant weight concentration of 4 g/100 mL, the viscosities of short-chain diionic poly-EO were higher and those of longer chain diionic poly-EO were lower than the viscosities of the nonionic poly-EO of the same chain lengths. These results were attributed to a predominant intramolecular aggregation of terminal ionic groups at low concentration of ionic groups in solution and predominant intermolecular aggregation at higher concentration of ionic groups. The results of bulk viscosity measurements as well as the results of differential scanning calorimetry measurements of the dependence of the glass transition temperature on the DP n of diionic poly-EO indicated that in bulk physically cross-linked networks were formed, due to intermolecular aggregation of terminal ionic groups.

The series of poly(oxyethylene)s (poly-EO) with number-average degrees of polymerization ranging from 6 to 80, terminated at both ends with phosphonium ion groups, was prepared by conversion of hydroxyl end groups of α-hydro-ω-hydroxypoly(oxyethylene)s into bromide end groups, followed by the reaction with triphenylphosphine. The functionality of the products (diionic poly-EO) was determined by elemental analysis, 1 H and 31 P NMR as well as mass spectroscopy (MS). The observation of the signals corresponding to individual oligomers in 31 P NMR spectra of short chain (DP n < 10) diionic poly-EO was explained by intramolecular aggregation of ionic end groups leading to cyclic structures. The measurements of spin lattice relaxation times and the chemical shifts of phosphorus at different conditions (temperature, solvent, concentration) confirmed, that the aggregation of ionic end groups is clearly manifested in the 31 P NMR spectra of diionic poly-EO.

The activity of poly(oxyethylenes), terminated at both ends with phosphonium ion groups, as catalysts in phase transfer reaction has been compared with this of the nonionic analogs. The observed moderate enhancement of activity for diionically terminated poly(oxyethylenes) may be attributed to increasing alkali metal complexing ability, due to the intramolecular aggregation of the ionic end-groups resulting in the formation of cyclic structure.

Macromonomers were obtained by cationic polymerization of propylene oxide and epichlorohydrin proceeding by the activated monomer mechanism with hydroxyethyl acrylate as initiator. Up to DPn ∼ 15 for propylene oxide and DPn ∼ 20 for epichlorohydrin, polymerization proceeds as a living process, giving with quantitative yields macromonomers with functionality equal to one, controlled molecular weight and narrow molecular weight distribution (MwMn

Epichlorohydrin (ECH) was polymerized by an activated monomer mechanism (AM) in the presence of benzoin (B) and α-methylol benzoinmethylether (MBME), respectively. Spectroscopic studies showed that polymers obtained via this initiation method contained benzoin terminal groups

The production of hypochlorous acid (HOCl) is a characteristic of granulocyte activation, a hallmark of the early phase of innate immune responses. In this study, we show that, in addition to its well-established role as a microbicide, HOCl can act as a natural adjuvant of adaptive immunity. HOCl enhances the T cell responses to the model Ag OVA, facilitating the processing and presentation of this protein via the class II MHC pathway. HOCl modification also enhances cross-presentation of the tumor Ag tyrosinase-related protein 2 via class I MHC. The adjuvant effects of HOCl are independent of TLR signaling. The enhanced presentation of HOCl-modified OVA is mediated via modification of the N-linked carbohydrate side chain rather than formation of protein aldehydes or chloramines. HOCl-modified OVA is taken up more efficiently by APCs and is degraded more efficiently by proteinases. Atomic force microscopy demonstrated that enhanced uptake is mediated via specific receptor binding, one candidate for which is the scavenger receptor lectin-like oxidized low-density lipoprotein receptor, which shows enhanced binding to chlorinated OVA. A function of HOCl is therefore to target glycoprotein Ags to scavenger receptors on the APC surface. This additional mechanism linking innate and adaptive immunity suggests novel strategies to enhance immunity to vaccines.

Taurine chloramine (TauCl) and Taurine bromamine (TauBr), products of the neutrophil myeloperoxidase halide system, exert anti-inflammatory properties. They inhibit the production of a variety of inflammatory mediators, such as prostaglandin E2 (PGE2), nitric oxide (NO) and proinflammatory cytokines. Heme oxygenase–1 (HO-1), a stress inducible enzyme, degrades heme to biliverdin, free iron and carbon monoxide (CO), which are involved in the anti-inflammatory and antioxidant actions of HO-1. Recently we have demonstrated that taurine haloamines induce the expression of HO-1 in inflammatory cells. In this study we examined whether HO-1 participates in taurine haloamines-mediated suppression of proinflammatory cytokine production. We have shown that TauCl/TauBr and CO inhibit the production of TNF-α, IL-12 and IL-6, in a similar dose-dependent manner. However, the suppressor activity of TauCl was not altered in HO-1 deficient mice. Therefore, HO-1 and TauCl may independently regulate the production of pro-inflammatory cytokines. We suggest that TauCl and TauBr provide a link between the two antioxidant systems: the cysteine pathway and the heme oxygenase system.

Green tobacco sickness (GTS) is an illness associated with exposure to nicotine originating directly from the growing tobacco plant. The exposure takes place in the course of activities during tobacco farming. Nausea, vomiting, headache and dizziness are the symptoms typical of GTS. The GTS cases have been most commonly reported in the USA, Japan, India and Italy. The first case of GTS in Poland has been diagnosed in a young man working on a Virginia bright tobacco plantation. The patient had symptoms typical of GTS. The toxicological analysis of urine demonstrated the presence of cotinine at the level of 869 ng/ml. Intravenous fluids, anticholinergic agents and potassium supplementation were used in the treatment. Interestingly, diplopia at the initial stage of tobacco poisoning and horizontal nystagmus, which resolved on the 2nd day of hospital stay were observed. We believe that cases of GTS occur in Poland; however patients do not seek medical care. Given that the majority of activities during tobacco farming in Poland are performed manually, it seems necessary to launch a public awareness campaign on GTS and decontamination methods.

Separation and extraction conditions for four atypical neuroleptics (clozapine, N-desmethylclozapine (active metabolite of clozapine), olanzapine, and quetiapine) and one classical neuroleptic (perazine) in human plasma have been studied. Reverse phase chromatography (RP-18) with the mobile phase consisted of: A. aq. orthophosphoric acid with addition of N,N,N′,N′-tetramethylethylendiamine (TEMED), pH = 5.0, and B. acetonitrile, in gradient flow, was selected. As the optimal liquid-liquid extraction conditions, sample pH = 11.6, extraction system, ethyl acetate/n-hexane/isopropanol (16:3:1, v/v/v), and back extraction into 0.01% orthophosphoric acid were chosen.

Polymerization of epichlorohydrin (ECH) in the presence of diols, catalyzed by Lewis or protic acids, proceeds by activated monomer mechanism (AMM), i.e., by subsequent additions of protonated monomer molecules to the terminal hydroxyl groups of the growing chain. As opposed to the typical active chain end mechanism, side reactions, including cyclization, are strongly suppressed in the polymerization by AMM and well-defined linear product are obtained. It follows from kinetic considerations, that in order to achieve the high contribution of AMM, the reaction should be carried out at low instantaneous concentration of monomer, and this can be accomplished by slowly adding ECH to the reaction mixture. Using this approach, polyepichlorophydrin diols have been prepared in the Mn ∼ 2500 products with DPn = [M]0/[I]0 can be obtained practically free of cyclic by-products with the yields approaching quantitative. Polyepichlorohydrin diols obtained by AM polymerization are strictly bifunctional, regular head-to-tail polymers containing mainly (≥ 95%) secondary hydroxyl and groups.

In the Activated Monomer (AM) polymerization of substituted oxiranes (propylene oxide - PO, epichlorohydrin - ECH), the microstructure of the chain is governed exclusively by the kinetics of the propagation step. In the copolymerization of ECH with 5-membered (tetrahydrofuran - THF) or 6-membered (1,4-dioxane - Diox) cyclic ethers, the distribution of comonomer units depends on both kinetic and thermodynamic factor, which allows preparation of oligodiols having regular (i.e. alternating) distribution of comonomer units in the chain.

Polymerization of cyclic ethers by activated monomer mechanism involves consecutive additions of protonated monomer molecules to the growing macromolecules fitted with hydroxyl groups at their ends. For oxirane itself and symmetrically substituted oxiranes there is only one kind of hydroxyl groups and one, unique way of ring-opening. Unsymmetrically substituted oxiranes provide however two sites of attack and two different hydroxyls, resulting from these ring-openings. Kinetics of polymerization of epichlorohydrin (chloromethyloxirane) has been studied and all four rate constants determined, namely rate constants of the primary and secondary alcoholate chain ends with a protonated monomer, opening in result of the attack on substituted or unsubstituted carbon atom. These rate constants are (in mol−1·1·s−1 at 25°C, in CH2Cl2 solvent): k11 = 0.055, k12 = = 0.41, k22 = 0.135, and k21 = 0.0011 (e.g. k12 is the rate of reaction of the primary alcohol producing the secondary alcohol). Thus, polymerization proceeds almost exclusively on the secondary alcoholate groups, reproducing themselves (k22).

In this study, in an animal model of zymosan-induced peritonitis we have tested antiinflammatory properties of Taurolidine (TRD), a synthetic derivative of taurine. In vitro, the effect of TRD and HOCl treated TRD on peritoneal macrophages was compared with that of TauCl. We report that locally administered TRD (Taurolin) shows strong antiinflammatory properties. TRD inhibits vascular permeability increased by inflammatory stimuli; it also significantly attenuates the influx of neutrophils into the peritoneal cavity, as well as the production of pro-inflammatory cytokines (TNF-α, IL-6) by peritoneal exudate cells. Chlorination of TRD resulted in the formation of chloramine (TRD-Cl), as confirmed by characteristic UV spectra. Both TRD and TRD-Cl, more effectively than TauCl, inhibited the production of IL-6 by stimulated macrophages. The effect was not dependent on its well-known anti-endotoxin activity since TRD inhibited cytokine production by macrophages stimulated with either LPS or IFN-γ.

Objective and Design: The myeloperoxidase system of neutrophils generates chlorinating and brominating oxidants in vivo. The major haloamines of the system are taurine chloramine (TauCl) and taurine bromamine (TauBr). It has been demonstrated in vitro that TauCl exerts both antiinflammatory and anti-bacterial properties. Much less is known about TauBr. The present study was conducted to compare bactericidal and immunoregulatory capacity of TauBr with that of the major chlorinating oxidants: HOCl and TauCl. Moreover, the effect of nitrites and H2O2 on TauBr activity was investigated. Materials: TauBr was prepared by reaction of HOBr with taurine. The reaction was monitored by UV absorption spectra. Methods: Bactericidal activity of TauBr, TauCl and HOCl was tested by incubation of E. coli with the compounds and determined by the pour-plate method. To test the anti-inflammatory activity the compounds were incubated with LPS and IFN-γ stimulated murine peritoneal macrophages. The production of following mediators was measured: nitrites by Griess reaction; TNF-α, IL-6, IL-10, IL-12p40 using capture ELISA. In some experiments the compounds were incubated with either nitrites or H2O2. Results: In our experimental set-up TauBr and HOCl exerted strong bactericidal effects on E. coli (MBC = 110 μM and 8 μM, respectively), while TauCl (< 1000 μM) did not kill test bacteria. However, both, TauBr and TauCl, at noncytotoxic concentrations (< 300 μM) inhibited the cytokine and nitric oxide production by macrophages. H2O2 completely abolished the biological activities of TauBr but not those of TauCl. Nitrites did not affect any activity of TauBr or TauCl while they diminished the HOCl− mediated bacterial killing. Conclusion: TauBr, despite very low concentration of Br− in body fluids, may support TauCl and HOCl in the regulation of inflammatory response and in killing of bacteria by neutrophils. However, TauBr activity in vivo will depend on the presence of H2O2 and possible other mediators of inflammation which can compete with target molecules for TauBr.

BACKGROUND: Non-Hodgkin’s lymphomas (nHL) may spread via blood vasculature or lymphatics. Vascular endothelial growth factor (VEGFs) family of glycoproteins is essential for angiogenesis and lymphangiogenesis. VEGF-C enhances lymphangiogenesis and promotes metastasis via lymphatic vessels. VEGF-C stimulates lymphangiogenesis by binding VEGFR-2 and VEGFR-3 receptors on lymphatic endothelial cells Elevated serum levels of proangiogenic cytokines (i.e. VEGF) are the independent prognostic factor in nHL. Data concerning the role of lymphangiogenesis in nHL are very limited. Salven et al. showed low VEGF -C mRNA in lymphoma cells. The role of lymphangiogenesis in lymphoma dissemination remains to be determined. The aim of the study was to assess plasma levels of VEGF-C and sVEGFR3 in nHL patients. before chemotherapy and after achieving complete remission (CR). MATERIAL AND METHODS: Plasma samples from 39 adult (18 females and 21 males) patients with B-cell nHL taken at diagnosis and in CR were measured by ELISA to evaluate VEGF-C and sVEGFR-3 levels (Bender Medsystems and R&D Systems respectively). In addition plasma samples from 25 healthy volunteers were evaluated as the control. Statistical analysis was performed using U Mann-Whitney test (p RESULTS: There was no significant differences in VEGF-C levels between untreated nHL group, nHL in CR and the control (166,9±221,8 vs 217±294,4 vs 161,2±118 pg/ml respectively). In untreated nHL patients sVEGFR3 level was significantly higher than in the control (19434±8990 vs 13949±5417 pg/ml respectively; p=0,007). In CR sVEGFR3 decreased but was still significantly higher than in healthy control (18163±9108 vs 13949±5417 pg/ml respectively; p=0,038). CONCLUSION: Similarly to previous studies we demonstrated that VEGF-C plasma levels were not increased in nHL. There are several observation that in human tumors VEGFR3 is involved both in lymphangiogenesis and angiogenesis. Increased VEGFR3 in nHL may reflect intensity of blood and lymphatic endothelium proliferation.

Leukotriene B(4) (LTB(4)) and cysteinyl leukotrienes (CysLTs) are known as potent mediators of inflammation, whereas their role in the regulation of adaptive immunity remains poorly characterized. Dendritic cells (DCs) are specialized antigen-presenting cells, uniquely capable to initiate primary immune responses. We have found that zymosan, but not lipopolysaccharide (LPS) stimulates murine bone marrow-derived dendritic cells (BM-DCs) to produce large amounts of CysLTs and LTB(4) from endogenous substrates. A selective inhibitor of leukotriene synthesis MK886 as well as an antagonist of the high affinity LTB(4) receptor (BLT(1)) U-75302 slightly inhibited zymosan-, but not LPS-stimulated interleukin (IL)-10 release from BM-DCs. In contrast, U-75302 increased zymosan-stimulated release of IL-12 p40 by approximately 23%. Pre-treatment with transforming growth factor-beta1 enhanced both stimulated leukotriene synthesis and the inhibitory effect of U-75302 and MK886 on IL-10 release from DCs. Consistent with the effects of leukotriene antagonists, exogenous LTB(4) enhanced LPS-stimulated IL-10 release by approximately 39% and inhibited IL-12 p40 release by approximately 22%. Both effects were mediated by the BLT(1) receptor. Ligands of the high affinity CysLTs receptor (CysLT(1)), MK-571 and LTD(4) had little or no effect on cytokine release. Agonists of the nuclear LTB(4) receptor peroxisome proliferator-activated receptor-alpha, 8(S)-hydroxyeicosatetraenoic acid and 5,8,11,14-eicosatetraynoic acid, inhibited release of both IL-12 p40 and IL-10. Our results indicate that both autocrine and paracrine leukotrienes may modulate cytokine release from DCs, in a manner that is consistent with previously reported T helper 2-polarizing effects of leukotrienes.

Introduction: 1-Methylnicotinamide (MNA), a major metabolite of nicotinamide (NA), is known to exert anti-inflammatory effects in vivo. Treatment of inflammatory skin diseases by topical application of MNA provides certain advantages over the use of NA. However, in contrast to NA, the molecular mechanisms of the anti-inflammatory properties of MNA are not well known. In this study the influence of exogenous MNA and NA in vivo on the generation of inflammatory mediators by macrophages (Mϕ) was investigated. Materials and Methods: Peritoneal Mϕ of CBA/J mice were activated in vitro with lipopolysaccharide and incubated with MNA or NA. The effect of these compounds on biological functions of Mϕ was measured by evaluation of the production of reactive oxygen species (ROS) by luminol-dependent chemiluminescence, cytokines and prostaglandin E2 (PGE2) by ELISA, and nitric oxide (NO) by the Griess method. Moreover, the expressions of inducible NO synthase and cyclooxygenase-2 were measured by Western blotting. Results: It was shown that at non-cytotoxic concentrations, NA inhibits the production of a variety of pro-inflammatory agents, such as tumor necrosis factor α, interleukin 6, NO, PGE2, and the generation of ROS. In contrast to NA, exogenous MNA inhibited only the generation of ROS, while its effect on the synthesis of other mediators was negligible. Conclusions: These results indicate that the anti-inflammatory properties of MNA demonstrated previously in vivo do not depend on its capacity to suppress the functions of immune cells, but more likely may be related to its action on vascular endothelium. The authors suggest that the limited permeability for exogenous MNA, in contrast to that for NA, may be responsible for its lack of suppressor activity against Mϕ.