Search

The COVID-19 pandemic underscores the need for rapid, safe, and effective vaccines. In contrast to some traditional vaccines, nanoparticle-based subunit vaccines are particularly efficient in trafficking antigens to lymph nodes, where they induce potent immune cell activation. Here, we developed a strategy to decorate the surface of oxidation-sensitive polymersomes with multiple copies of the SARS-CoV-2 spike protein receptor-binding domain (RBD) to mimic the physical form of a virus particle. We evaluated the vaccination efficacy of these surface-decorated polymersomes (RBDsurf) in mice compared to RBD-encapsulated polymersomes (RBDencap) and unformulated RBD (RBDfree), using monophosphoryl-lipid-A-encapsulated polymersomes (MPLA PS) as an adjuvant. While all three groups produced high titers of RBD-specific IgG, only RBDsurf elicited a neutralizing antibody response to SARS-CoV-2 comparable to that of human convalescent plasma. Moreover, RBDsurf was the only group to significantly increase the proportion of RBD-specific germinal center B cells in the vaccination-site draining lymph nodes. Both RBDsurf and RBDencap drove similarly robust CD4+ and CD8+ T cell responses that produced multiple Th1-type cytokines. We conclude that a multivalent surface display of spike RBD on polymersomes promotes a potent neutralizing antibody response to SARS-CoV-2, while both antigen formulations promote robust T cell immunity., We developed nanoscale polymer vesicles (polymersomes) decorated with multiple copies of SARS-CoV-2 antigen as a COVID-19 vaccine that elicits neutralizing antibodies and cellular immunity.

Objectives To evaluate the primary patency rate at three years for the infra-aortic peripheral arterial pathologies treated with polytetrafluoroethylene-covered stent-grafts. Methods Patients treated with self-expandable polytetrafluoroethylene-covered stent-grafts for infra-aortic peripheral arterial aneurysms, pseudo-aneurysms, and arterio-venous fistulas were evaluated retrospectively. A total of 48 patients (35 male, 13 female; mean age: 53.8 ± 13.5) were included with 29.0 ± 16.5 months (median 27, range 4–70) mean follow-up period. The primary objective was to determine the primary patency rate at three years. The secondary objectives were to compare type and localization of pathology, and length and diameter of the stent-grafts with primary patency rate. Kaplan–Meier test was used as the main statistical method. Results Overall mean primary patency rate at three years was 77.10%. Polytetrafluoroethylene-covered stent-graft implantation in aneurysms had worse primary patency rate than pseudo-aneurysms and arterio-venous fistulas (66.6%, P = 0.03; 76.9%, P = 0.03; 88.2%, P = 0.01, respectively). Stent-graft location, length, and diameter are not associated with primary patency rate ( P > 0.05) but stent diameter is associated with better primary assisted and secondary patency rates ( P Conclusions Pathology of the lesion is associated with the long-term primary patency rate of polytetrafluoroethylene-covered stent-grafts but not the stent-graft location, length, or diameter. Stent diameter is associated with primary assisted and secondary patency rates.

The SARS-CoV-2 virus has caused an unprecedented global crisis, and curtailing its spread requires an effective vaccine which elicits a diverse and robust immune response. We have previously shown that vaccines made of a polymeric glyco-adjuvant conjugated to an antigen were effective in triggering such a response in other disease models and hypothesized that the technology could be adapted to create an effective vaccine against SARS-CoV-2. The core of the vaccine platform is the copolymer p(Man-TLR7), composed of monomers with pendant mannose or a toll-like receptor 7 (TLR7) agonist. Thus, p(Man-TLR7) is designed to target relevant antigen-presenting cells (APCs) via mannose-binding receptors and then activate TLR7 upon endocytosis. The p(Man-TLR7) construct is amenable to conjugation to protein antigens such as the Spike protein of SARS-CoV-2, yielding Spike-p(Man-TLR7). Here, we demonstrate Spike-p(Man-TLR7) vaccination elicits robust antigen-specific cellular and humoral responses in mice. In adult and elderly wild-type mice, vaccination with Spike-p(Man-TLR7) generates high and long-lasting titers of anti-Spike IgGs, with neutralizing titers exceeding levels in convalescent human serum. Interestingly, adsorbing Spike-p(Man-TLR7) to the depot-forming adjuvant alum, amplified the broadly neutralizing humoral responses to levels matching those in mice vaccinated with formulations based off of clinically-approved adjuvants. Additionally, we observed an increase in germinal center B cells, antigen-specific antibody secreting cells, activated T follicular helper cells, and polyfunctional Th1-cytokine producing CD4+ and CD8+ T cells. We conclude that Spike-p(Man-TLR7) is an attractive, next-generation subunit vaccine candidate, capable of inducing durable and robust antibody and T cell responses.

A diverse portfolio of SARS-CoV-2 vaccine candidates is needed to combat the evolving COVID-19 pandemic. Here, we developed a subunit nanovaccine by conjugating SARS-CoV-2 Spike protein receptor binding domain (RBD) to the surface of oxidation-sensitive polymersomes. We evaluated the humoral and cellular responses of mice immunized with these surface-decorated polymersomes (RBDsurf) compared to RBD-encapsulated polymersomes (RBDencap) and unformulated RBD (RBDfree), using monophosphoryl lipid A-encapsulated polymersomes (MPLA PS) as an adjuvant. While all three groups produced high titers of RBD-specific IgG, only RBDsurf elicited a neutralizing antibody response to SARS-CoV-2 comparable to that of human convalescent plasma. Moreover, RBDsurf was the only group to significantly increase the proportion of RBD-specific germinal center B cells in the vaccination-site draining lymph nodes. Both RBDsurf and RBDencap drove similarly robust CD4+ and CD8+ T cell responses that produced multiple Th1-type cytokines. We conclude that multivalent surface display of Spike RBD on polymersomes promotes a potent neutralizing antibody response to SARS-CoV-2, while both antigen formulations promote robust T cell immunity.

OZGUMUS, SAADET/0000-0002-1793-0859; Cevher, Erdal/0000-0002-0486-2252; GOK, MEHMET KORAY/0000-0003-2497-9359 WOS:000488123900052 PubMed: 31386881 Nasal vaccination is considered to be an effective and convenient way of increasing immune responses both systemically and locally. Although various nanovaccine carriers have been introduced as potential immune adjuvants, further improvements are still needed before they can be taken to clinical usage. Chitosan-based nanovaccine carriers are one of the most widely studied adjuvants, owing to the ability of chitosan to open tight junctions between nasal epithelial cells and enhance particle uptake as well as its inherent immune activating role. In present study, bovine serum albumin (BSA) loaded nanoparticles were prepared using novel aminated (aChi) and aminated plus thiolated chitosan (atChi) polymers, to further enhance mucoadhesiveness and adjuvanticity of the vaccine system by improving electrostatic interactions of polymers with negatively charged glycoproteins. Nanocarriers with optimum size and surface charge, high encapsulation efficiency of model antigen and good stability were developed. Negligible toxicity was observed in Calu-3 and A549 cell lines. In vivo studies, revealed high levels of systemic antibodies (IgG, IgG(1) and IgG(2a)) throughout the study and presence of sIgA in vaginal washes showed that common mucosal system was successfully stimulated. Cytokine levels indicated a mixed Th1/Th2 immune response. A shift towards cellular immune responses was observed after nasal immunisation with antigen loaded nanoparticle formulations. These nanoparticles exhibit great potential for nasal application of vaccines. Scientific Research Projects Coordination Unit of Istanbul UniversityIstanbul University [36160]; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) This work was supported by Scientific Research Projects Coordination Unit of Istanbul University, No: 36160. Genada Sinani acknowledges The Scientific and Technological Research Council of Turkey (TUBITAK) for the PhD Fellowship Program.

Iznik Lake is an important water supply deteriorating gradually due to anthropogenic pollution. Concentration and distribution of monoaromatic hydrocarbons (benzene, toluene, ethylbenzene and three xylene isomers; BTEX) were detected in the lake sediments using a static headspace GC-MS. ∑BTEX concentrations varied between 10.6 and 272.3 µg kg-1 dry weight (dw), with an average of 88.3 µg kg-1 dw. The light aromatic fraction of m-,p-Xylene was the most abundant compound (50.0% in average), followed by toluene (31.2%), o-xylene (12.2%), ethylbenzene (5.3%) and benzene (1.3%). Multivariate statistical analyses indicated that the BTEX levels and their distributions were controlled mainly by morphological and textural features of the sediment; anthropogenic inputs transported by the surrounding rivers, mainly influenced by agricultural facilities; absorbance of BTEX compounds in sediment; and biodegradation processes. Due to lack of any national sediment quality guideline regarding BTEX, the results will establish a significant baseline that will shed light on the administrative authorities for formulating their rational environmental strategies.

In the present study, a simple, cheap and sensitive electrochemical method based on a cathodically pretreated boron-doped diamond (CPT-BDD) electrode is described for the detection of triclosan with the cationic surfactant (cetyltrimethylammonium bromide, CTAB) media. The oxidation of triclosan was irreversible and exhibited an adsorption controlled process. The sensitivity of the adsorptive stripping voltammetric measurements was significantly improved with addition of CTAB. Using square-wave stripping mode, a linear response was obtained for triclosan determination in Britton-Robinson buffer solution at pH 9.0 containing 2.5 x 10(-4) M CTAB at around + 0.67 V (vs. Ag/AgCl) (after 30 s accumulation at open-circuit condition). The method could be used in the range of 0.01-1.0 mu g mL(-1) (3.5 x 10(-8)-3.5 x 10(-6) M), with a detection limit of 0.0023 mu g mL(-1) (7.9 x 10(-9) M). The feasibility of the proposed method for the determination of triclosan in water samples was checked in spiked tap water.

The reaction of [2-(Me 2 NCH 2 )C 6 H 4 ]HgCl ( 1 ) with NH 4 Br and KI gave the analogous bromide ( 2 ) and iodide ( 3 ), respectively. To investigate the competitive coordination to the mercury centre of the nitrogen atom of the pendant arm and the donor atoms of a potentially chelating anionic ligand the dithiocarbamates [2-(Me 2 NCH 2 )C 6 H 4 ]HgS(S)CNR 2 [R = Me ( 4 ), Et ( 5 )] were prepared by reacting 1 with Na[S 2 CNR 2 ]·nH 2 O (R = Me, n = 2; R = Et, n = 3). The reaction between PhHgCl and the same sodium dithiocarbamates afforded PhHgS(S)CNR 2 [R = Me ( 6 ), Et ( 7 )]. The compounds were investigated by multinuclear NMR spectroscopy ( 1 H, 13 C, 199 Hg and 2D experiments) and mass spectrometry. The solid-state molecular structures of compounds 2 – 6 were established by single-crystal X-ray diffraction. In the compounds 2 – 5 the nitrogen atom of the pendant CH 2 NMe 2 arm is strongly coordinated to the mercury atom. The ( C,N )HgX core is non-planar in the dithiocarbamates 4 and 5 and thus the mercury atom becomes a stereocentre. Supramolecular associations based on Hg⋯X, Hg⋯S, C-H⋯X (X = Br, I), S⋯S and C-H⋯π interactions are discussed.

Receptor internalization by endocytosis regulates diverse cellular processes, from the rate of nutrient uptake to the timescale of essential signaling events. The established view is that internalization is tightly controlled by specific protein-binding interactions. However, recent work suggests that physical aspects of receptors influence the process in ways that cannot be explained by biochemistry alone. Specifically, work from several groups suggests that increasing the steric bulk of receptors may inhibit their uptake by multiple types of trafficking vesicles. How do biochemical and biophysical factors work together to control internalization? Here, we show that receptor uptake is well described by a thermodynamic trade-off between receptor-vesicle binding energy and the entropic cost of confining receptors within endocytic vesicles. Specifically, using large ligands to acutely increase the size of engineered variants of the transferrin receptor, we demonstrate that an increase in the steric bulk of a receptor dramatically decreases its probability of uptake by clathrin-coated structures. Further, in agreement with a simple thermodynamic analysis, all data collapse onto a single trend relating fractional occupancy of the endocytic structure to fractional occupancy of the surrounding plasma membrane, independent of receptor size. This fundamental scaling law provides a simple tool for predicting the impact of receptor expression level, steric bulk, and the size of endocytic structures on receptor uptake. More broadly, this work suggests that bulky ligands could be used to drive the accumulation of specific receptors at the plasma membrane surface, providing a biophysical tool for targeted modulation of signaling and metabolism from outside the cell.

The reaction of Ph3BiCl2 with alkali salts of isonicotinic and nicotinic acids afforded Ph3Bi[O(O)CC5H4N-4]2 (1) and Ph3Bi[O(O)CC5H4N-3]2 (2), respectively, which were characterized by multinuclear NMR spectroscopy in solution, mass spectrometry and IR spectroscopy in the solid state. Their molecular structures were established by single-crystal X-ray diffraction. For both 1 and 2 the molecules contain a trigonal bipyramidal C3BiO2 core, with the phenyl groups in equatorial positions. The potential use of 1 and 2 as ditopic organometalloligands was investigated. The reaction of 1 or 2 with Me3SnCl (1 : 2 molar ratio) resulted in carboxylato ligand exchange and the formation of Me3Sn[O(O)CC5H4N-4] (3) and Me3Sn[O(O)CC5H4N-3] (4) besides Ph3BiCl2. The crystals of both 3 and 4 contain 1-D coordination polymers built through intermolecular N → Sn interactions. The treatment of Ni[S2P(OiPr)2]2 with 1 and 2, respectively, resulted, in addition to di(carboxylato)nickel(II) derivatives, in isolation of Ph3Bi and the disulphane [(iPrO)2P(S)S]2. New coordination polymers were obtained by reacting 1 and 2 with various silver(I) salts: [Ag{Ph3Bi[O(O)CC5H4N-4]2}(OTf)] (5), [Ag{Ph3Bi[O(O)CC5H4N-3]2}(OTf)]·CH2Cl2 (6·CH2Cl2), [Ag{Ph3Bi[O(O)CC5H4N-4]2}](SbF6)·2THF (7·2THF), [Ag{Ph3Bi[O(O)CC5H4N-3]2}](SbF6)·CH2Cl2 (8·CH2Cl2) and [Ag{Ph3Bi[O(O)CC5H4N-3]2}(NO3)]·CH2Cl2 (9·CH2Cl2). The crystal structures of 5 and 6 can be described as 1-D chains linked by triflate bridges in pairs of chains and 2-D networks, respectively. Compound 7 features a 2-D grid-like topology of the network, with tecton 1 acting as a tridentate ligand through both nitrogen and one oxygen atoms. The linker 2 molecules adopt either cis (compound 6) or trans (compounds 8 and 9) conformation. Complexes 8 and 9 are 1-D chain polymers exhibiting zig-zag and wavy motifs, respectively. The dimensionality of the structures is extended by the presence of supramolecular interactions (π⋯π, Ag⋯Ag, Ag⋯O).

The SARS-CoV-2 virus has caused an unprecedented global crisis, and curtailing its spread requires an effective vaccine which elicits a diverse and robust immune response. We have previously shown that vaccines made of a polymeric glyco-adjuvant conjugated to an antigen were effective in triggering such a response in other disease models and hypothesized that the technology could be adapted to create an effective vaccine against SARS-CoV-2. The core of the vaccine platform is the copolymer p(Man-TLR7), composed of monomers with pendant mannose or a toll-like receptor 7 (TLR7) agonist. Thus, p(Man-TLR7) is designed to target relevant antigen-presenting cells (APCs) via mannose-binding receptors and then activate TLR7 upon endocytosis. The p(Man-TLR7) construct is amenable to conjugation to protein antigens such as the Spike protein of SARS-CoV-2, yielding Spike-p(Man-TLR7). Here, we demonstrate Spike-p(Man-TLR7) vaccination elicits robust antigen-specific cellular and humoral responses in mice. In adult and elderly wild-type mice, vaccination with Spike-p(Man-TLR7) generates high and long-lasting titers of anti-Spike IgGs, with neutralizing titers exceeding levels in convalescent human serum. Interestingly, adsorbing Spike-p(Man-TLR7) to the depot-forming adjuvant alum amplified the broadly neutralizing humoral responses to levels matching those in mice vaccinated with formulations based off of clinically-approved adjuvants. Additionally, we observed an increase in germinal center B cells, antigen-specific antibody secreting cells, activated T follicular helper cells, and polyfunctional Th1-cytokine producing CD4+ and CD8+ T cells. We conclude that Spike-p(Man-TLR7) is an attractive, next-generation subunit vaccine candidate, capable of inducing durable and robust antibody and T cell responses.

The concentrations and distribution of monoaromatic hydrocarbons (benzene, toluene, ethyl benzene and the sum of m -, p - and o -, xylenes) were determined in the sediments of coastal lagoons of the Gulf of Saros, using a static headspace GC–MS. The total concentrations of BTEX compounds ranged from 368.5 to below detection limit 0.6 μg kg − 1 dw, with a mean value of 61.5 μg kg − 1 dw. The light aromatic fraction of m -, p -xylene was the most abundant compound (57.1% in average), and followed by toluene (38.1%) > ethylbenzene (4.1%) > o-xylene (2.5%) > benzene (1.1%). The factor analysis indicated that the levels and distribution of BTEX compounds depend on the type of contaminant source (mobile/point), absorbance of compounds in sediment, and mobility of benzene compound and degradation processes. Point sources are mainly related to agricultural facilities and port activities while the dispersion of compounds are related with their solubility, volatility and effect of sea/saline waters on lagoons.

The aim of this study was to evaluate the use of cationic–hydrophilic copolymers for self-assembly with antisense oligonucleotides targeted to the bcl-2 mRNA in order to improve their biocompatibility and modulation of their pharmacokinetics for greater therapeutic usefulness. Examination of the ability of poly(trimethylammonioethyl methacrylate chloride)–poly[N-(2-hydroxypropyl)methacrylamide] (pHPMA-b-pTMAEM) block copolymers to condense the oligonucleotide by fluorescence and electrophoresis techniques showed that complexes were formed more efficiently than with copolymers containing poly(ethylene glycol) blocks grafted onto the backbone of poly(l-lysine) (pLL-g-pEG). In addition, the copolymer pTMAEM-b-pHPMA produced oligonucleotide complexes with the most favourable physicochemical properties appropriate for in vivo applications. The complexes were small (approximately 36 nm in diameter), with low surface charge as measured by zeta potential, relatively stable to physiological salt conditions and could be formed at a DNA concentration of 500 μg/ml. Complex formation with the copolymer pTMAEM-b-pHPMA or pLL-g-pEG reduced the urinary clearance of the oligonucleotide after intravenous injection into mice. However after 30 min, the oligonucleotide complexes were cleared from the bloodstream. These results indicate that for the systemic delivery of oligonucleotides the polymer-derived complexes are not stable enough for prolonged circulation. Instead, these complexes may be more suitable for localised in vivo applications.

Cevher, Erdal/0000-0002-0486-2252 WOS:000369970100005 PubMed: 26480962 Here, we aimed at developing chitosan/pullulan composite nanoparticles and testing their potential as novel systems for the nasal delivery of diphtheria toxoid (DT). All the chitosan derivatives [N-trimethyl (TMC), chloride and glutamate] and carboxymethyl pullulan (CMP) were synthesised and antigen-loaded composites were prepared by polyion complexation of chitosan and pullulan derivatives (particle size: 239-405 nm; surface charge: +18 and +27 mV). Their immunological effects after intranasal administration to mice were compared to intramuscular route. Composite nanoparticles induced higher levels of IgG responses than particles formed with chitosan derivative and antigen. Nasally administered TMC-pullulan composites showed higher DT serum IgG titre when compared with the other composites. Co-encapsulation of CpG ODN within TMC-CMP-DT nanoparticles resulted in a balanced Th-1/Th-2 response. TMC/pullulan composite nanoparticles also induced highest cytokine levels compared to those of chitosan salts. These findings demonstrated that TMC-CMP-DT composite nanoparticles are promising delivery system for nasal vaccination.

Cevher, Erdal/0000-0002-0486-2252; OZGUMUS, SAADET/0000-0002-1793-0859; GOK, MEHMET KORAY/0000-0003-2497-9359 WOS:000408009200001 PubMed: 28629979 Mucosal vaccination stimulates both mucosal and systemic immunity. However, mucosal applications of vaccine antigens in their free form generally result in poor systemic immune responses and need adjuvantation. In this study, bovine serum albumin loaded, new hybridised poly(beta-amino ester)-poly( D, Llactide-co-glycolide) nanoparticles were prepared by double emulsion-solvent evaporation method, characterised and evaluated in vivo as nasal vaccine carriers. Cationic spherical particles with a mean size of 240 nm, good physical stability and high encapsulation efficiency were obtained. Protein structure was not affected throughout preparation and minimal toxicity was shown in Calu-3 and A549 cells. Nasal vaccination with these nanoparticles revealed markedly higher humoral immune responses compared with free antigen following intranasal and subcutaneous immunisation. Mucosal immune response was also stimulated and cytokine titres indicated that Th1 and Th2 pathways were successfully activated. This study shows that the formulated hybrid nanoparticles can be a promising carrier for nasal immunisation of poor antigenic proteins. (C) 2017 Elsevier B.V. All rights reserved. Scientific Research Projects Coordination Unit of Istanbul UniversityIstanbul University [36160]; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) This work was supported by Scientific Research Projects Coordination Unit of Istanbul University, Project Number: 36160. Genada Sinani acknowledges The Scientific and Technological Research Council of Turkey (TUBITAK) for the PhD Fellowship Program.

Cobalt(II) complexes of type [Co{(XPR2)(O2SR′)N}2] [X = S; R = Ph; R′ = Me (1), Ph (2), C6H4CH3-4 (3); X = O; R = Ph, R′ = Ph (4), R = OEt, R′ = C6H4CH3-4 (5)] were prepared by salt metathesis reactions between CoCl2·6H2O and the potassium salt of the appropriate organophosphorus acid in a 1:2 M ratio. All compounds were characterized by UV–Vis spectroscopy in CH2Cl2 solutions, mass spectrometry, infrared spectroscopy and room temperature magnetic susceptibility. For compounds 1 and 5 electronic spectra were recorded in dimethylformamide (dmfa) as well. While the electronic spectra suggest a monomeric structure in CH2Cl2 solutions with a tetrahedral environment about cobalt(II), for compound 3 in solid state a dinuclear structure was determined by single-crystal X-ray diffraction, with two bridging S,O,O-bimetallic triconnective and two S,O-monometallic biconnective [(SPPh2)(O2SC6H4CH3-4)N]− ligand units. From a CH2Cl2 solution of 1 crystals of the oxidation product [Co(OH){(SPPh2)(O2SMe)N}2] (6) were isolated after standing for several weeks in open atmosphere. Compound 4 in dimethylformamide decomposed and formed the octahedral species [Co(O2PPh2)2(HO2PPh2)2(dmfa)2] (7) (dmfa = dimethylformamide). The redox behavior of 1 was investigated by cyclic voltammetry in CH2Cl2 solution.

The preparation, spectroscopic characterization (NMR and IR spectroscopy), and solid-state structures of tri(3-pyridyl)- and tri(4-pyridyl)phosphine chalcogenides (E = O, S, Se) as well as their ability to behave as ligands for ZnTPP (TPP = tetraphenylporphyrinate) moieties are reported. In the solid state, the compounds from this family are three-bladed molecular propellers that crystallize as racemates. Both triorganophosphine sulfides and selenides, (3-Py)3PE [Py = pyridyl, NC5H4; E = S (2), Se (3)] and (4-Py)3PE [E = S (6), Se (7)], quantitatively form complexes with ZnTPP by selective coordination of all three pyridyl groups of a molecular unit to three metalloporphyrin moieties. The formation of these complexes in chlorinated solvents is unambiguously proven by spectroscopic methods (i.e., multinuclear NMR and UV/Vis spectroscopy). The affinity of these ligands towards ZnTPP is different in benzene, yielding a mixture of products in solution.

An electrochemical sensor based on the electrocatalytic activity of graphene (GR) was prepared, and used for the individual, selective and simultaneous determination of 5-O-Caffeoylquinic acid (5-CQA) that is major compound of chlorogenic acids in coffee, vanillin (VAN) and caffeine (CAF). The electrochemical behaviors of these compounds on GR modified glassy carbon electrode (GR/GCE) were investigated by cyclic voltammetry and square-wave adsorptive stripping voltammetry. By using stripping conditions after 30s accumulation under open-circuit voltage, the electrochemical oxidation peaks appeared at +0.53, 0.83 and 1.39V in phosphate buffer pH2.5, and good linear current responses were obtained with detection limits of 4.4x10(-9), 5.0x10(-7), and 3.0x10(-7)M for 5-CQA, VAN and CAF, respectively. The potential applicability of the proposed method was illustrated in commercial food and beverage samples.

Bis(2-acetylphenyl)dichalcogenides of type [2-(O=CMe)C6H4]2E2 (E=S, Se, Te) were prepared by the hydrolysis of [2-{(CH2O)2C(CH3)}C6H4]2E2. In their reaction with benzylamine these species yield an air-sensitive condensation product, which undergoes a fast, unexpected oxidative intramolecular cyclization. This process proved to be a very convenient way to prepare 3-amino substituted benzo[b]chalcogenophenes. By contrast, the reaction between [2-(O=CMe)C6H4]TeCl and benzylamine resulted in the condensation product [2-(C6H4CH2N=CMe)C6H4]TeCl.

The reaction of RMCl2 [R = 2,6-[MeN(CH2CH2)2NCH2]2C6H3; M = Sb (1), Bi (2)] with KOH affords the isolation of the oxides cyclo-R2M2O2 [M = Sb (3), Bi (4)]. Treatment of 3 with trifluoroacetic acid produced an ionic species (5) with a dinuclear cation that contains organic ligands protonated partially at one of the pendant arms. The cyclic oxides 3 and 4 are able to trap gaseous CO2 to give “RMCO3” [M = Sb (6), Bi (7)], the degree of these organometallic carbonates’ oligomerization being under investigation. The reactivity of the dinuclear oxide 3 was also investigated towards oxalic acid or dopamine hydrochloride and pure mononuclear compounds could be isolated, i.e. RSb[O(O)CC(O)O] (8) and RSb[O2-1,2-C6H3-3-(CH2)2NH3]Cl (9). The reaction of the dichlorides 1 and 2 with ethylene glycol, pinacol or catechol, in the presence of KOH, led to 2-organo-1,3,2-dioxastibolanes or -bismolanes RM(OCH2)2 [M = Sb (10), Bi (11)], RM(OCMe2)2 [M = Sb (12), Bi (13)] and 2-organo-1,3,2-dioxastibole or -bismole RM(O2-1,2-C6H4) [M = Sb (14), Bi (15)], respectively. The compounds were investigated by NMR spectroscopy, including variable temperature experiments, providing evidence for the presence of the intramolecular N→M interactions in solution. Single crystal X-ray diffraction studies were performed for most compounds and revealed an organic group R acting as a pincer ligand resulting in a distorted square pyramidal (N,C,N)MO2 core with cis intramolecular N→M interactions placed trans to M–O bonds. This is in contrast to the N→M interactions trans to each other as found in the RMCl2 used as starting materials. The crystals of the oxides 3 and 4·4H2O contain different geometric isomers with anti and syn orientation of the M–C bonds, respectively, with respect to the planar M2O2 ring. In the supramolecular polymeric architecture established in the crystal of 4·4H2O an important finding is the experimental observation of water hexamer units with a [tetramer + 2] structure (water molecules connected to opposite corners of a square water tetramer) fixed between 1D-chains of the type (syn-R2Bi2O2·H2O)n through additional hydrogen bonds to oxygen atoms of the dinuclear organobismuth(III) moieties. Theoretical calculations were carried out on 2–6 and 8–15 in order to gain insight into the stabilization energy produced by intramolecular coordination of the pendant arms, association degrees and formation energies of the organopnicogen compounds with chelating ligands.

The simultaneous voltammetric determination of melatonin (MT) and pyridoxine (PY) has been carried out at a cathodically pretreated boron-doped diamond electrode. By using cyclic voltammetry, a separation of the oxidation peak potentials of both compounds present in mixture was about 0.47 V in Britton-Robinson buffer, pH 2. The results obtained by square-wave voltammetry allowed a method to be developed for determination of MT and PY simultaneously in the ranges 1-100 mu g mL(-1) (4.3x10(-6)-4.3x10(-4) mol L-1) and 10-175 mu g mL(-1) (4.9x10(-5)-8.5x10(-4) mol L-1), with detection limits of 0.14 mu g mL(-1) (6.0x10(-7) mol L-1) and 1.35 mu g mL(-1) (6.6x10(-6) mol L-1), respectively. The proposed method was successfully to the dietary supplements samples containing these compounds for health-caring purposes.

The effect of suspension stabilizers, internal aqueous phase volume and polymer amount were investigated for the production of protein loaded poly(d,l lactide-co-glycolide) (PLGA) microparticles suitable for pulmonary drug delivery. PLGA microparticles were produced adopting water-in-oil-in-water (W/O/W) solvent evaporation technique and were investigated for surface morphology, particle size, encapsulation efficiency (EE%) and in-vitro release profile. Porous surface morphologies with a narrow size distribution were observed when employing 0.5 ml internal aqueous phase; 23.04 µm (± 0.98), 15.05 µm (± 0.27) and 22.89 µm (±0.41) for PVA, Tween 80 and oleic acid. Porous microparticles exhibited increased size and reduction in EE% with increasing internal aqueous phase, with non-porous microparticles produced when adopting 2.0 ml internal aqueous phase. The selection of stabilizer influences the size of the pores formed thus offers potential for the aerodynamic properties of the microparticles to be manipulated to achieve suitable aerosolization characteristics for pulmonary delivery of proteins.

Cevher, Erdal/0000-0002-0486-2252; WOS:000369970100004 PubMed: 26480961 Nasal immunisation with nanoparticles has already shown promising results. In this study, nanoparticle composites carrying BSA for nasal vaccination prepared using electrostatic interaction process between polycation N-trimethyl chitosan chloride (TMC), chitosan glutamate (CG), chitosan chloride (CCl) and polyanion carboxymethyl pullulan (CMP). A mass ratio of 2:1 for TMC-CMP combination produced stable nanocarriers. For CCl-CMP and CG-CMP formulations needed a mass ratio of 3:1. Loading efficiency was >90% for all formulations. Nanoparticles' size ranged from 207 to 603 nm. The surface charge of the complexes varied between +14 and +33 mV. SDS-PAGE integrity of the model antigen was also demonstrated. MTT studies showed that nanoparticle composites were less toxic to Calu-3 cells than the particles of cationic polymers alone. FITC-BSA loaded nanoparticles efficiently taken up by J774A.1 macrophages as confirmed by confocal microscopy highlighting the potential of these novel nanoparticulate carriers' use for nasal vaccination.

Highly viscous mucus poses a big challenge for the delivery of particulates carrying therapeutics to patients with cystic fibrosis. In this study, surface modifying DNase I loaded particles using different excipients to achieve better lung deposition, higher enzyme stability or better biological activity had been exploited. For the purpose, controlled release microparticles (MP) were prepared by co-spray drying DNase I with the polymer poly-lactic-co-glycolic acid (PLGA) and the biocompatible lipid surfactant 1,2-dipalmitoyl-Sn-phosphatidyl choline (DPPC) using various hydrophilic excipients. The effect of the included modifiers on the particle morphology, size, zeta potential as well as enzyme encapsulation efficiency, biological activity and release had been evaluated. Powder aerosolisation performance and particle phagocytosis by murine macrophages were also investigated. The results showed that more than 80% of enzyme activity was recovered after MP preparation and that selected surface modifiers greatly increased the enzyme encapsulation efficiency. The particle morphology was greatly modified altering in turn the powders inhalation indices where dextran, ovalbumin and chitosan hydrochloride increased considerably the respirable fraction compared to the normal hydrophilic carriers lactose and PVP. Despite of the improved aerosolisation caused by chitosan hydrochloride, yet retardation of chitosan coated particles in artificial mucus samples discouraged its application. On the other hand, dextran and polyanions enhanced DNase I effect in reducing cystic fibrosis mucus viscosity. DPPC proved good ability to reduce particles phagocytic uptake even in the presence of the selected adjuvants. The prepared MP systems were biocompatible with lung epithelial cells. To conclude, controlled release DNase I loaded PLGA-MP with high inhalation indices and enhanced mucolytic activity on CF sputum could be obtained by surface modifying the particles with PGA or dextran.

In this study, the spray drying technique was used to prepare ciprofloxacin microparticles (CFX-MPs) for pulmonary administration. By virtue of its amphoteric properties, CFX was dissolved in either a slightly alkaline or acidic solution depending on the used polymer. Dextran and chitosan were used to prepare the MPs and modify the release characteristics of the drug. Particle surface modification was done with either DPPC or PEG. The effects of the manufacturing and formulation parameters on the drug–polymer interactions were investigated by thermal analysis and infrared spectroscopy. CFX-MPs showed improved aerosolisation properties and the encapsulated drug possessed high antimicrobial activity against two of the common and resistant respiratory pathogens: Pseudomonas aeruginosa and Staphylococus aureus. MPs were safe on the lung epithelial cells. Modulation of particle characteristics and drug release was possible by altering not only the polymer but also the type of the acid from which the powders were spray dried. MPs prepared with glutamic and aspartic acids showed better characteristics than those prepared with acetic and hydrochloric acids. Dextran modified particles showed improved aerosolisation properties and safety on lung epithelial cells.

Several organophosphorus acids of type [{XP(OEt)2}(O2SR)]NH [X = O, R = Me (1), Ph (2), C6H4CH3-4 (3); X = S, R = C6H4Cl-4 (4)] were obtained by a method based on the reaction between (EtO)2P(X)NHLi and the corresponding organosulfonyl chloride. They were subsequently deprotonated with KOBut. Salt metathesis reactions between PdCl2 and the corresponding potassium salts K[{XP(OEt)2}(O2SR)N] [X = O, R = Me (5), Ph (6), C6H4CH3-4 (7); X = S, R = C6H4Cl-4 (8)] in a 1:2 molar ratio resulted in palladium(II) complexes of type Pd[{XP(OEt)2}(O2SR)N]2 [X = O, R = Me (9), Ph (10), C6H4CH3-4 (11); X = S, R = C6H4Cl-4 (12)]. In a similar way was obtained the palladium(II) complex Pd[(SPPh2)(O2SPh)N]2 (13), using the appropriate reagents. All compounds were characterized by multinuclear NMR (1H, 13C, 31P) and infrared spectroscopy. The potassium salts and the palladium complexes were investigated also by mass spectrometry. Single-crystal X-ray diffraction studies revealed a layered supramolecular assembly in case of acid 1, a monomeric structure for compound 4, while in case of compound 2 dimeric associations are formed in the solid state by NH⋯OP hydrogen bonding. A trans-S,N-coordination pattern of the organophosphorus ligand was found in the palladium complex 12. Moreover, short Cl⋯H contacts result in a polymeric [Pd[{SP(OEt)2}(O2SC6H4Cl-4)N]2]n chain.

The objective of the present study was to characterize the short-term biomechanical properties of cast micro/macroporous poly(caprolactone) (PCL) tubes intended for application as tissue integrating blood vessel substitutes. Micro/macroporous PCL vascular grafts (5.5 mm internal diameter, 7.5 mm external diameter) with defined macropore structures were produced by rapidly cooling PCL solutions containing dispersed gelatin particles in dry ice, followed by solvent and gelatin extraction. A Bose-Enduratec BioDynamic chamber configured for cardiovascular applications was used to measure the diametrical stability (dilation) of tubular samples under hydrodynamic flow conditions at 37 °C. Microporous PCL tubes withstood the hydrodynamic stresses induced by short, 2-min duration flow rates up to 1000 mL/min, which resulted in estimated internal pressures in excess of arterial pressure (80–130 mmHg). Micro/macroporous PCL tubes having a maximum macroporosity of 23% accommodated the hydrodynamic stresses generated by short duration, flow rates up to 1000 mL/min, which resulted in estimated internal pressures similar to venous pressure (30 mmHg).The dilation of microporous PCL tubes under short, (5 min) pulsatile flow conditions (1 Hz) increased from 10 to 100 μm with increasing mean flow rate from 50 to 500 mL/min. Both microporous and macroporous tubes exhibited a burst strength higher than 900 mmHg under hydrostatic fluid pressure, which is in excess of arterial pressure (80–130 mmHg) by a factor of approximately 7. Quantitative analysis of the macropore structure was performed using micro-computed tomography for correlation with mechanical properties and cell growth rates. Mouse fibroblasts efficiently colonized the external surface of macroporous PCL materials over 8 days in cell culture and cell numbers were higher by a factor of two compared with microporous PCL. These findings demonstrate that micro/macroporous PCL tubes designed for vascular tissue engineering can accommodate the hydrodynamic stresses generated by short duration, simulated blood flow conditions and exhibit good potential for integration with host tissue.

The new organophosphorus proligand (OPPh2)(O2SMe)NR (R = C6H3Pri 2–2,6) (3) was prepared as a white crystalline solid by reacting the lithiated compound Li[Ph2P(O)NR] with MeSO2Cl in a 1:1 molar ratio. The precursor Ph2P(O)NHR (1), as well as its thio analogue Ph2P(S)NHR (2), were obtained in the reaction between the lithiated amine RNHLi and the corresponding organophosphorus chloride. All compounds were characterized by multinuclear (1H, 13C, and 31P) NMR spectroscopy. The molecular structures of 1–3 were established by single-crystal X-ray diffraction. A zigzag polymeric chain is formed in the crystals of 1 and 2 by hydrogen N–H···X (X = O, S) bonding, while the crystal of 3 contains discrete monomeric units with a syn–syn conformation of the O˭P(C)2–N–S(C)(˭O)2 skeleton. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.

The reaction between gold(I) and silver(I) starting materials with anionic organophosphorus ligands of type [(SPPh2)(O2SR)N]- resulted in new group 11 complexes of the type [Au{(SPPh2)(O2SR)N}(tht)] (tht = tetrahydrothiophene), [Au{(SPPh2)(O2SR)N}(PPh3)], PPN[Au{(SPPh2)(O2SR)N}2] [PPN = bis(triphenylphosphine)iminium], [Ag{(SPPh2)(O2SR)N}] and [Ag{(SPPh2)(O2SR)N}(PPh3)] (R = Me, Ph, C6H4CH3-4). The new derivatives were structurally characterized by 1H and 31P NMR spectroscopy, as well as infrared and mass spectrometry. Single-crystal X-ray diffraction studies revealed monomeric structures for the gold(I) species [Au{(SPPh2)(O2SMe)N}(PPh3)] (4) and [Au{(SPPh2)(O2SC6H4Me-4)N}(PPh3)] (6), while a dimeric association was found for the silver(I) compound [Ag{(SPPh2)(O2SPh)N}(PPh3)]2·2CH2Cl2 (14·2CH2Cl2). The organophosphorus(V) ligand units have different coordination patterns, i.e. S-monometallic monoconnective in 4, S,O-monometallic biconnective in 6 and S,S,O-bimetallic triconnective in 14, respectively. © 2009 Elsevier B.V. All rights reserved., Financial support from the Ministry of Education and Research of Romania (CNCSIS, Research Project No. 1456/2007-2008) is greatly appreciated. A.P. is grateful for a research fellowship awarded by the ‘‘Babes-Bolyai” University, Cluj-Napoca, Romania.

Kurt, Emine Bahar/0000-0002-3495-2339; Ada, Ahmet Oguz/0000-0001-9987-0572; Suzen, Sinan/0000-0003-1779-5850 WOS: 000286494400004 PubMed: 20845989 Several polymorphisms in cytochrome P-450s (CYP)s and Glutathione S-transferases (GST)s have been reported to be associated with survival rates of patients with non-small cell lung cancer (NSCLC) but the studies in this regard are scarce and the results are contradictory. In this study, CYP1A1 (Ile462Val), CYP1B1(Asn453Ser), GST M1, GSTP1 exon 5 (Ile105Val) and exon 6(Ala114Val) and GSTT1 polymorphisms were determined in 138 patients with advanced NSCLC to evaluate their role in survival. Of the studied GYP and GST polymorphisms only GSTP1 exon 6 variant significantly altered (improved) the survival compared to wild type (p=0.036) with median survival of 22.2 months and 16.1 months, respectively. Multivariate analysis also revealed a significant reduction of adjusted hazard ratio of death associated only with the GSTP1 exon 6 variant genotype of 0.45(95% confidence interval (95% CI), 0.23-0.89,p=0.022). These results show that the GSTP1 exon 6 variant genotype is associated with improved survival in the patients with advanced NSCLC. Research Fund of Ankara UniversityAnkara University [2006-08-03-002 HPD, 2007-08-03-005 HPD] This research was supported by the grants from Research Fund of Ankara University Nos: 2006-08-03-002 HPD and 2007-08-03-005 HPD

Simultaneously Manufactured Nano-In-Micro (SIMANIM) particles for the pulmonary delivery of antibodies have been prepared by the spray-drying of a double-emulsion containing human IgG (as a model antibody), lactose, poly(lactide-co-glycolide) (PLGA) and dipalmitoylphosphatidylcholine (DPPC). The one-step drying process involved producing microparticles of a diameter suitable for inhalation that upon contact with aqueous media, partially dissolved to form nanoparticles, approximately 10-fold smaller than their original diameter. Continuous release of the model antibody was observed for 35 days in pH 2.5 release media, and released antibody was shown to be stable and active by gel electrophoresis, field-flow fractionation and enzyme linked immunosorbent assay. Adding 1% L-leucine to the emulsion formulation, and blending 'SIMANIM' particles with 1% magnesium stearate, achieved a fine particle fraction of approximately 60%, when aerosolised from a simple, capsule-based, dry powder inhaler device. 'SIMANIM' particles could be beneficial for the delivery of antibodies targeted against inhaled pathogens or other extracellular antigens, as well as having potential applications in the delivery of a wide range of other biopharmaceuticals and certain small-molecule drugs.

Strangles is an infectious disease caused by Streptococcus equi subspecies equi that affects the upper respiratory tract of the Equidae. The control of this disease seems to be dependent on its earlier detection and prevention, but prolonged animal protection without development of strong and severe side effects has not yet been achieved. Convalescent horses exhibit a protective immune response, mainly against SeM (58 kDa), an antiphagocytic and opsonogenic S. equi M-like protein, known as the major protective antigen against strangles. Purified recombinant SeM and S. equi protein extract-entrapped poly(lactic acid) (PLA) nanospheres were developed and their adjuvant potential was studied via the intramuscular route. The effect including molecules with adjuvant properties such as spermine, oleic acid, alginate and glycol-chitosan was also evaluated. Spherical nanometric particles 500 nm containing the protein antigen were prepared by the solvent evaporation method and protein structure was not affected throughout preparation. The humoral immune response induced by nanospheres was markedly higher than that elicited by soluble antigens, isolated or co-admixed with CpG. The IgG and IgG subtypes, along with cytokine titres, indicated that nanospheres composed by glycolchitosan developed a more balanced Th1/Th2 response for both purified SeM and S. equi enzymatic extract proteins, although those induced by the pure antigen-entrapped particles were higher than the S. equi tested vaccines composed by total antigens entrapped in polymeric nanospheres. (C) 2009 Elsevier Ltd. All rights reserved.. - Portuguese Ministry of Science and Technology [SFRH/BD/14300/2003, POCI/BIO/59147/2004, PPCDT/BIO/59147/2006]. - work was supported by research grants awarded by the Portuguese Ministry of Science and Technology (SFRH/BD/14300/ 2003; POCI/BIO/59147/2004; PPCDT/BIO/59147/2006).

The eastern and southern coasts of the Gulf of Gemlik, a resort in the Sea of Marmara, Turkey, are under the influence of rapid ecotourism development, direct domestic and industrial discharges via rivers and outfalls, surface run-off, drainage from ports and shipping. According to sediment quality criteria in use around the world, sediment quality in the gulf shows a broad spectrum. It is more related by direct input, rather than by the type of sediment, and excluding inner port and southern coasts, it does not exert adverse biological effects yet. The total PAH concentrations range from 51 to 13,482 ng/g dry weight with the mean value of 1,850 ng/g dry weight (n = 61). The elevated values of the total toxic Benzo[a]pyrene equivalency (TEQcarc), with a maximum of 1,838 ng/g dry weight, were found at the inner harbor of Gemlik, possibly posing hazard to benthic organisms. Among the different PAHs, the contribution to the total TEQcarc decreased as the following order: Benzo[a]pyrene (43.6%) > Benzo[k]fluoranthene (36.0%) > Indeno[1,2,3-cd]pyrene (35.1%) > Benzo[b]fluoranthene (20.0%) > Chrysene + Triphenylene (18.9%) > Benzo[a]anthracene (12.5%).

Therapeutic antibodies offer a potential treatment for, or means of protection against, airborne infections. For this application, it may be desirable to deliver the antibody directly into the nasal cavity, one of its potential sites of action, since this would be more efficient and convenient than systemic administration. Formulations of a model antibody (human IgG) were developed using albumin, sodium chloride and disaccharides. A combination of these excipients allowed the efficient spray-drying (yield>70%) of the antibody into a microparticulate (1-15 microm) dry powder that was rapidly soluble in aqueous media. The water content and crystallinity of the formulations were also measured, with both properties being affected by the substitution of some of the sodium chloride in the formulation, with lactose. The antibody was found to be stable following the formulation process, as determined by gel-electrophoresis, field-flow-fractionation and enzyme-linked immunosorbent assay. Incubation of an in vitro epithelial cell line in the presence of solutions of the formulations (at concentrations of up to 2500 microg/mL) was found not affect cell viability. The aerosolisation properties of the formulations were tested using Bespak's "Unidose-DP", dry-powder nasal device. The powder aerosol was analysed by laser diffraction, high-speed video and dose deposition in Bespak's nasal cast model. For the latter experiment, a range of additional excipients were either dissolved in the spray-drying liquid feed (leucine), or blended with the spray-dried powder formulation (magnesium stearate, Aerosil and lactose). The major dose deposition site of the standard spray-dried formulation was the nasal vestibule (approximately 55%). The addition of leucine and Aerosil resulted in a 10% increase in the deposition beyond the nasal vestibule, with approximately 45% of the delivered dose being deposited in the turbinates, olfactory region, and nasal-pharynx.

Double emulsion solvent evaporation is a widely used method to prepare poly(dl-lactide-co-glycolide) (PLGA) microparticles encapsulating plasmid DNA. There are inherent problems associated with preparing plasmid DNA in this form, in particular the DNA is liable to degrade during manufacture and the resulting powder has low encapsulation efficiencies. This study compares the use of two buffers, 0.1M NaHCO(3) and 0.07M Na(2)HPO(4) and the effect these have on the encapsulation efficiency and other critical parameters associated with these encapsulated DNA materials. Both buffers preserved the conformation of the original plasmid DNA during the homogenization process, but those made with 0.07M Na(2)HPO(4) had higher encapsulation efficiencies, as well as smaller diameters, compared with those made with 0.1M NaHCO(3) (encapsulation efficiencies of 40.72-45.65%, and mean volume diameters of 2.96-4.45microm). Buffers with a range of pH from 5 to 12 were investigated, and it was demonstrated that pH 9 was the point at which the highest amount of supercoiled DNA was balanced with the highest encapsulation efficiency. To simulate in vitro release, it was shown that microparticles made with 0.07M Na(2)HPO(4) had lower DNA release rates than those made with 0.1M NaHCO(3). These results demonstrate that the use of different buffers can aid in retaining the conformation of plasmid DNA, and can also modulate the amount of DNA encapsulated and the release profiles of microparticles.

Low-frequency ultrasound application is known to increase the skin's permeability to large molecules such as vaccines, and to enable transcutaneous immunisation. Sodium dodecyl sulphate (SDS) - a skin irritant - is often included in the coupling medium at 1% (w/v), as this has been found to enhance skin permeability. In this paper we show, for the first time, the feasibility of low-frequency ultrasound-assisted transcutaneous immunisation in the absence of SDS. Antibody titres were strongly influenced by experimental conditions. SDS presence in the coupling medium increased antibody titres, though a lower concentration of 0.5% (w/v) generated much higher titres than the commonly used 1% (w/v), despite causing less skin damage. A lower ultrasound duty cycle of 10% generated higher antibody titres than a duty cycle of 20%, also despite causing lower skin damage. Such lack of correlation between skin damage and immune responses indicates that enhancement of skin permeability to topically applied antigen (as indicated by changes in skin integrity) was not the main mechanism of low-frequency ultrasound-assisted skin immunisation.

Mucosal application of a vaccine can effectively induce both systemic and mucosal immune responses. In general, mucosal applications of antigens result in poor immune responses. Therefore, adjuvant/delivery systems are required to enhance the immune response. Chitosan is a cationic biopolymer which exerts advantages as a vaccine carrier due to its immune stimulating activity and bioadhesive properties that enhance cellular uptake and permeation as well as antigen protection. Similar effects are also shown by chitosan derivatives. In this study, the nanoparticulate systems were prepared by using differently charged chitosan derivatives, N-trimethyl chitosan (TMC, polycationic), and mono-N-carboxymethyl chitosan (MCC, polyampholytic) for mucosal immunisation. The derivatives were synthesised and characterised in-house. The aqueous dispersions of the derivatives were also prepared for comparison. The cytotoxicity studies (MTT assay) on Chinese hamster ovary (CHO-K1) cell lines showed that cell viability was in the order of MCC, chitosan and TMC. Nanoparticles were prepared using ionic gelation method and loaded with tetanus toxoid (TT). Nanoparticles with high loading efficacy (>90% m/m), particle size within the range of 40-400nm, with a negative surface charge for MCC and positive surface charge for TMC and chitosan were obtained. The structural integrity of the TT in the formulations was confirmed by SDS-PAGE electrophoresis analysis. The effective uptake of the FITC-BSA loaded nanoparticles into the cells was demonstrated by cellular uptake studies using J774A.1 cells. Immune responses induced by the formulations loaded with tetanus toxoid were studied in vivo in Balb/c mice. Enhanced immune responses were obtained with intranasal (i.n.) application of nanoparticle formulations. Chitosan and TMC nanoparticles which have positively charged surfaces induced higher serum IgG titres when compared to those prepared with MCC which are negatively charged and smaller in size. Nanoparticle formulations developed in this study can be used as promising adjuvant/delivery systems for mucosal immunisation.

The aim of this work was to investigate lipid-based dried powders as transfection competent carriers capable of promoting the expression of therapeutic genes. The lipid-based vectors were prepared by combining different cationic lipids 1,2-dioleoyl-3-trimethylammoniumpropane chloride (DOTAP), 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE), 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and 3beta(N(N',N-dimethylaminoethane) carbamoyl) cholesterol hydrochloride (DC-Chol) or by mixing of anionic lipids (1,2-dimyristoyl-sn-glycero-3-phospocholine (DMPC), 1,2-dimyristoyl-sn-glycero-3-phospho-rac-glycerol sodium salt (DMPG) and chitosan salts. Spray drying of the formulations was performed using carbohydrates as thermoprotectant excipients and some amino acids as aerosolisation enhancers. Both the lipidic vectors and the dried powders were characterized for morphology, size, zeta potential (Z-potential) and a yield of the process. Agarose gel electrophoresis was used to examine the structural integrity of dehydrated plasmid DNA (pDNA). The biological functionality of the powders was quantified using the in vitro cell transfection. Among the several lipids and lipid-polymer mixtures tested, the best-selected formulations had spherical shape, narrow size distribution (mean diameter220 nm, P.I.0.250), a positive zeta-potential (25 mV) with a good yield of the process (65%). The set-up spray drying parameters allowed to obtain good yield of the process (50%) and spherically shaped particles with the volume-weighted mean diameter (d[4,3])6 microm in the respirable range. The set-up conditions for the preparation of the lipid dried powders did not adversely affect the structural integrity of the encapsulated pDNA. The powders kept a good transfection efficiency as compared to the fresh colloidal formulations. Lipid-based spray dried powders allowed the development of stable and viable formulations for respiratory gene delivery. In vitro dispersibility and deposition studies are in progress to determine the aerosolisation properties of the powders.

In this study, poly(D,L-lactide-co-glycolide) (PLGA)-chitosan particles were investigated as an effective delivery system for small interfering RNA (siRNA) by emulsification diffusion method. The type, molecular weight and concentration of chitosan, PLGA type as well as centrifugation and freeze-drying process were amongst the investigated variables. PLGA-chitosan particles obtained were positively charged with particle size between approximately 0.4-1 microm depending on type, molecular weight and concentration of chitosan as well as type of PLGA. A better siRNA loading capacity was observed when a higher degree of 'uncapped end groups' were used. The addition of trehalose has also been shown to stabilize these particles from severe aggregation induced by freeze-drying. It was found that physical properties of PLGA-chitosan particles and their siRNA binding capacity were highly influenced by certain preparation parameters. The desired positive charge of submicron size range PLGA-chitosan particles could therefore be obtained by adjusting and optimizing these preparative and formulation parameters.

The chemical fingerprinting approach to environmental assessment is illustrated in the evaluation of marine oil pollution on the coasts of the suburb of Florya (Marmara Sea). The samples of unknown origin collected during three leg expeditions on April 2003, December 2003, and February 2004 were analyzed by gas chromatography coupled with mass spectrometry (GC/MS). Hydrocarbon distribution patterns of samples indicated different known and unknown origins. The group hydrocarbon compositions of the samples from leg one are the same as those from the cargo oil spill of tanker Volgoneft-248, which ran aground after structural failure. When it broke apart at the end of the year 1999, tons of oil were spilled into the Marmara Sea. The results show that the remainder of the buried oil in the seabed may come ashore during strong onshore winds even after comprehensive clean-up operations and after 4 years. On the other hand, the samples collected during legs 2 and 3 appear to be from unknown sources.

Poly (L-lactic acid) (PLA) microparticles encapsulating Hepatitis B surface antigen (HBsAg) with alum and chitosan were investigated for their potential as a vaccine delivery system.The microparticles, prepared using a water-in-oil-in-water (w/o/w) double emulsion solvent evaporation method with polyvinyl alcohol (PVA) or chitosan as the external phase stabilising agent showed a significant increase in the encapsulation efficiency of the antigen.PLA-Alum and PLA-chitosan microparticles induced HBsAg serum specific IgG antibody responses significantly higher than PLA only microparticles and free antigen following subcutaneous administration. Chitosan not only imparted a positive charge to the surface of the microparticles but was also able to increase the serum specific IgG antibody responses significantly.The cytokine assays showed that the serum IgG antibody response induced is different according to the formulation, indicated by the differential levels of interleukin 4 (IL-4), interleukin 6 (IL-6) and interferon gamma (IFN-gamma). The microparticles eliciting the highest IgG antibody response did not necessarily elicit the highest levels of the cytokines IL-4, IL-6 and IFN-gamma.

The reaction of dichalcogenides (I) with benzylamine (II) affords compounds (III), products of an unexpected oxidative intramolecular cyclization.

WOS: 000360077300014, PubMed: 26344968, In this study, grape molasses produced by using the traditional methods from the from TaAYkent town of Konya were analysed for their some quality values. Depending on the type of grape molasses and boiling periods, some differences were found in physico-chemical properties. Protein, pH, total acid, hydroximetil furfural, soluble dry matter, total phenol and viscosity values were found between 0.260 % and 0.421 %, 7.82 and 8.35 %, 0.477 % and 0.585 %, 3.312 mg/kg and 6.336 mg/kg, 20.447 mg/L and 25.813 mg/L, 61.5 and 67.0 % and 65.60 mPa.s to 91.75 mPa.s, respectively. Antioxidant activity values were determined between % 86.437 and % 93.395. L* values were established between 20.41 and 55.29, while a* values are found between 8.11 and 18.69 and b* values are between 34.94 and 47.47. The K, Mg, Na, P, Ca contents of all the molasses samples has been detected at high levels. At some quality parameters such as protein, total acid and L* values have been decreased towards to end of the boiling period. As a result, antioxidant activity and anthocyanin in the red grape molasses were superior to compared with other types of grape molasses., Selcuk University Scientific Research Project (S.U.-BAP, Konya-Turkey)Selcuk University, This study was supported by Selcuk University Scientific Research Project (S.U.-BAP, Konya-Turkey). The authors wish to thank BAP Staffs.

Titration calorimetry was used to investigate the interaction between a model antigen, bovine serum albumin (BSA), and a model particulate carrier, polystyrene (PS). The binding enthalpy was much higher than reported in the literature for a similar system and did not display a sigmoidal binding curve. These experiments may have accessed low coverage surface sites due to the irreversible nature of protein binding and stepwise titration. An important correction is the heat of dilution of the protein solution. Two regimes were observed: at low concentrations of BSA (below ca. 0.3% (w/v)) an exothermic dilution enthalpy of ca. -100 mJ mg-1 was determined, whereas at higher concentrations of BSA values of ca. -20 mJ mg-1 were obtained. Solution rheological data also showed a change at 0.3% (w/v) BSA, so we hypothesise that the fraction of the BSA as monomers, dimers and polymers in solution changes at approximately 0.3% (w/v).

The nasal mucosa has many advantages as a potential site for drug and vaccine delivery. The present study has sought to exploit this route of delivery using microparticles composed of D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) as a matrix material blended with poly(caprolactone) for nasal immunisation with diphtheria toxoid. Particles were prepared by a double emulsion method, followed by spray drying and the effect of TPGS on size, zeta potential, loading and release of antigen was assessed. Particles composed of TPGS-PCL blends were spherical, smooth and monodisperse, displaying increasing yields after spray drying with increasing concentrations of TPGS. The immune response to diphtheria toxoid loaded PCL-TPGS microspheres after nasal administration was shown to be higher than that achieved using PCL microspheres alone. We conclude that TPGS shows significant potential as a novel adjuvant either alone or in combination with an appropriate delivery system.

The aim of this study was to further investigate the interactions between cholesterol (CH) and mixed bile salts (BS) (sodium cholate and sodium deoxycholate) and their suitability for drug and vaccine delivery. Insulin was used as a model protein to assess the ability of CH:BS vesicles to entrap a therapeutically relevant macromolecule. The association of protein (FITC-insulin) with the CH:BS structure was confirmed with fluorescence microscopy, and the overall morphology of the vesicles was examined with atomic force microscopy (AFM). Results demonstrate that the nature of the vesicles formed between CH and BS is dependent not only on the concentration of BS but also on the increasing CH concentration leading to CH crystal formation.

The aim of this study was to prepare stable liposomes coated or loaded with bioadhesive polymers and test their efficacy following oral, nasal (IN) or intramuscular (IM) delivery of diphtheria toxoid (DT) in raising systemic antibody responses. The stability of these liposomes in three different media mimicking gastrointestinal (GI) fluids of the stomach and small intestine was also examined. Fluorescence microscopy of the rat small intestine showed preferential adsorption/association of polymer-coated liposomes versus free FITC-BSA. Finally, the efficacy liposomes composed of dipalmitoylphosphatidylcholine, dicetyl phosphate and cholesterol (DPPC:DCP:CH, 7:3:2 molar ratio) for delivery of DT to mice was assessed. Immunisation through the IM route with these liposomes produced the highest DT specific serum IgG antibody titres; liposomes loaded with chitosan chloride were the only formulation to elicit a specific measurable IgG response when delivered orally with the present protocol. IN delivery of liposomes loaded with PVA resulted in a significantly better IgG antibody response (p < 0.05) when compared to uncoated liposomes.