Multidirectional effects of Sr, Mg and Si-containing bioceramic coatings with high bonding strength on inflammation, osteoclastogenesis and osteogenesis

Ideal coating materials for implants should be able to induce excellent osseointegration, which requires several important parameters, such as good bonding strength, limited inflammatory reaction, balanced osteoclastogenesis and osteogenesis, to gain well-functioning coated implants with long-term life span after implantation. Bioactive elements, like Sr, Mg and Si, have been found to play important roles in regulating the biological responses. It is of great interest to combine bioactive elements for developing bioactive coatings on Ti-6Al-4V orthopedic implants to elicit multidirectional effects on the osseointegration. In this study, Sr, Mg and Si-containing bioactive Sr2MgSi2O7 (SMS) ceramic coatings on Ti-6Al-4V were successfully prepared by plasma-spray coating method. The prepared SMS coatings have significantly higher bonding strength (~37MPa) than conventional pure hydroxyapatite (HA) coatings (mostly in the range of 15-25 MPa). It was also found that the prepared SMS coatings switch the macrophage phenotype into M2 extreme, inhibiting the inflammatory reaction via the inhibition of Wnt5A/Ca2+ and Toll-like receptor (TLR) pathways of macrophages. In addition, the osteoclastic activities were also inhibited by SMS coatings. The expression of osteoclastogenesis related genes (RANKL and MCSF) in bone marrow derived mesenchymal cells (BMSCs) with the involvement of macrophages was decreased, while OPG expression was enhanced on SMS coatings compared to HA coatings, indicating that SMS coatings also downregulated the osteoclastogenesis. However, the osteogenic differentiation of BMSCs with the involvement of macrophages was comparable between SMS and HA coatings. Therefore, the prepared SMS coatings showed multidirectional effects, such as improving bonding strength, reducing inflammatory reaction and downregulating osteoclastic activities, but maintaining a comparable osteogenesis, as compared with HA coatings. The combination of bioactive elements of Sr, Mg and Si into bioceramic coatings can be a promising method to develop bioactive implants with multifunctional properties for orthopaedic application.

Voltage quality improvement in distribution networks containing DERs using UPQC

Single phase distributed energy resources (DERs) can cause voltage rise along distribution feeder and power imbalance among the phases. Usually transformer tap setting are used to mitigate voltage drop along feeders. However this can aggravate the voltage rise problem when DERs are connected. Moreover if the power generation in a phase is more than its load demand, the excess power in that phase will be fed back to the transmission network. In this paper, a unified power quality compensator (UPQC) has been utilized to alleviate the voltage quality excess power circulation problems. Through analysis and simulation results, the mode of operation of UPQC is highlighted. The proposals are validated through extensive digital computer simulation studies using PSCAD and MATLAB.

Anionic migration reactions in aromatic systems effected by collisional activation : Deprotonated anilides containing methoxycarbonyl substituents

Long-range cross-ring reactions are of minor importance in the collision-induced mass spectra (MS/MS) of [M - H]- ions of CH2OCO-C6H4-NHCOR systems: e.g. the loss of 'CD3CO2CH3' from CH3OCO-C6H4-(N) over bar COCD3. Major processes involve (i) losses of radicals to form stable radical anions, e.g. loss of a ring hydrogen atom and losses from the ester (CH3 ., CH3O . and . CO2CH3), (ii) losses of neutral molecules from the amide moiety [e.g. CO (R = H) and CH2CO (R = CH3), and proximity effects when the two substituents are ortho [e.g. loss of (CH3OD+CO2) from o-CH3OCO-C6H4 (N) over bar COCD3].

Clinical dyslipidaemia is associated with changes in the lipid composition and inflammatory properties of apolipoprotein-B-containing lipoproteins from women with type 2 diabetes

The aim of this study was to use lipidomics to determine if the lipid composition of apolipoprotein-B-containing lipoproteins is modified by dyslipidaemia in type 2 diabetes and if any of the identified changes potentially have biological relevance in the pathophysiology of type 2 diabetes. VLDL and LDL from normolipidaemic and dyslipidaemic type 2 diabetic women and controls were isolated and quantified with HPLC and mass spectrometry. A detailed molecular characterisation of VLDL triacylglycerols (TAG) was also performed using the novel ozone-induced dissociation method, which allowed us to distinguish vaccenic acid (C18:1 n-7) from oleic acid (C18:1 n-9) in specific TAG species. Lipid class composition was very similar in VLDL and LDL from normolipidaemic type 2 diabetic and control participants. By contrast, dyslipidaemia was associated with significant changes in both lipid classes (e.g. increased diacylglycerols) and lipid species (e.g. increased C16:1 and C20:3 in phosphatidylcholine and cholesteryl ester and increased C16:0 [palmitic acid] and vaccenic acid in TAG). Levels of palmitic acid in VLDL and LDL TAG correlated with insulin resistance, and VLDL TAG enriched in palmitic acid promoted increased secretion of proinflammatory mediators from human smooth muscle cells. We showed that dyslipidaemia is associated with major changes in both lipid class and lipid species composition in VLDL and LDL from women with type 2 diabetes. In addition, we identified specific molecular lipid species that both correlate with clinical variables and are proinflammatory. Our study thus shows the potential of advanced lipidomic methods to further understand the pathophysiology of type 2 diabetes.

Chemotaxis and chemokinesis of human prostate tumor cell lines in response to human prostate stromal cell secretory proteins containing a nerve growth factor-like protein

The migration of three human prostate tumor epithelial cell lines (TSU-pr1, PC-3, DU-145) in response to secreted protein from a human prostate stromal cell line was investigated by using the modified blind-well Boyden chamber assay. Migrated cells were quantified by spectrophotometrically measuring the concentration of crystal violet stain extracted from their nuclei. Cell number was correlated linearly with the concentration of extracted crystal violet stain. All three tumor cell lines showed intrinsic migratory ability in the absence of chemoattractants, such that approximately 1-7% of plated cells migrated across the filter of the Boyden chambers during a 5-h incubation period. Prostate tumor cell migration was significantly enhanced (3-13-fold) in response to stromal cell secretory protein in a dose-dependent manner, whereas bovine serum albumin had no effect on stimulating tumor cell migration. Immunoprecipitation of the stromal cell secreted protein with a nerve growth factor antibody partially and significantly reduced its stimulatory activity for tumor cell migration. A Zigmond-Hirsch matrix assay of tumor cell migration in response to various concentration gradients of stromal cell secreted protein demonstrated both chemotaxis and chemokinesis by all three cell lines. These results are consistent with the stromal cell secretory protein stimulation of chemokinetic tumor cell migration through the capsule of the prostate. Outside of the prostate gland metastasis of tumor cells may occur by chemotaxis to preferential sites containing chemoattractants similar to or related to maintenance factors that can substitute for components of stromal cell secretory protein.

Anionic migration in aromatic systems effected by collisional activation. Unusual fragmentations of deprotonated anilides containing methoxyl and ethoxyl substituents

Long-range cross-ring reactions occur when (M - H)(-) ions of methoxy- and ethoxy-C6H4-(-)NCOR (R = H, CH3, C6H5 and CH3O) are subjected to collisional activation, These reactions are generally minor processes: a particular example is the cross-ring elimination p-C2H5O-C6H4-(NCOCH3)-N-- --> [CH3-(p-C2H5O-C6H4-NCO)] --> p-(O--)-C6H4-NCO + C2H4 + CH4. Major processes of these (M - H)(-) ions involve (i) losses of radicals to form stabilised radical anions, e.g. (a) loss of a ring H-. or (b) CH3. (or C2H5.) from the alkoxy group, and (ii) proximity effects when the two substituents are ortho, e.g. loss of CH3OH from o-CH3O-C6H4-(NCHO)-N-- yields deprotonated benzoxazole. Another fragmentation of an arylmethoxyl anion involves loss of CH2O. It is proposed that losses of CH2O are initiated by anionic centres but the actual mechanisms in the cases studied depend upon the substitution pattern of the methoxyanilide: o- and p-methoxyanilides may undergo ipso proton transfer/elimination reactions, whereas the in-analogues undergo proton transfer reactions to yield an o-CH3O substituted aryl carbanion followed by proton transfer from CH3O to the carbanion site with concomitant loss of CH2O.

A light and electron microscopic study of NADPH-diaphorase-,calretinin- and parvalbumin-containing neurons in the rat nucleus accumbens

The rat nucleus accumbens contains medium-sized, spiny projection neurons and intrinsic, local circuit neurons, or interneurons. Sub-classes of interneurons, revealed by calretinin (CR) or parvalbumin (PV) immunoreactivity or reduced nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase histochemistry, were compared in the nucleus accumbens core, shell and rostral pole. CR, PV and NADPH-diaphorase-containing neurons are shown to form three non-co-localising populations in these three areas. No significant differences in neuronal population densities were found between the subterritories. NADPH-diaphorase-containing neurons could be further separated morphologically into three sub-groups, but CR- and PV-immunoreactive neurons form homogeneous populations. Ultrastructurally, NADPH-diaphorase-, CR- and PV-containing neurons in the nucleus accumbens all possess nuclear indentations. These are deeper and fewer in neurons immunoreactive for PV than in CR- and NADPH-diaphorase-containing neurons. CR-immunoreactive boutons form asymmetrical and symmetrical synaptic specialisations on spines, dendrites and somata, while PV-immunoreactive boutons make only symmetrical synaptic specialisations. Both CR- and PV-immunoreactive boutons form symmetrical synaptic specialisations with medium-sized spiny neurons and contact other CR- and PV-immunoreactive somata, respectively. A novel non-carcinogenic substrate for the peroxidase reaction (Vector Slate Grey, SG) was found to be characteristically electron-dense and may be distinguishable from the diaminobenzidine reaction product. We conclude that the three markers used in this study are localised in distinct populations of nucleus accumbens interneurons. Our studies of their synaptic connections contribute to an increased understanding of the intrinsic circuitry of this area.

New approaches to the synthesis of strapped porphyrin containing bipyridinium [2]rotaxanes

Inspired by the interesting photo- and electrochemical properties observed in bipyridinium and porphyrin containing interlocked catenanes, herein we describe new approaches towards the synthesis of related rotaxanes. Previous efforts in this domain had been hampered by the limited range of chemical reactions that are compatible with these motifs, however the use of a “click” methodology, together with a better understanding of the size of these strapped porphyrin macrocycles, resulted in the synthesis of a bipyridinium porphyrin [2]rotaxane in modest yields. X-ray crystallography of the zinc metalloporphyrin macrocycle used in this study revealed that in the solid state, these strapped porphyrins adopt a 1-dimensional coordination polymer, in which an oxygen atom in the strap of one macrocycle is coordinated to the zinc metal center in an adjacent porphyrin ring

Sulfur-containing amide-based [2]rotaxanes and molecular shuttles

We report the synthesis, structure and properties of [2]rotaxanes prepared by the assembly of benzylic amide macrocycles around a series of amide and sulfide-/sulfoxide-/sulfone-containing threads. The efficacy of rotaxane formation is related to the hydrogen bond accepting properties of the various sulfur-containing functional groups in the thread, with the highest yields (up to 63% with a rigid vinyl spacer in the template site) obtained for sulfoxide rotaxanes. X-Ray crystallography of a sulfoxide rotaxane, 5, shows that the macrocycle adopts a highly symmetrical chair-like conformation in the solid state, with short hydrogen bonds between the macrocycle isophthalamide NH-protons and the amide carbonyl and sulfoxide S-O of the thread. In contrast, in the X-ray crystal structures of the analogous sulfide (4) and sulfone (6) rotaxanes the macrocycle adopts boat-like conformations with long intercomponent NH…O=SO and NH…S hydrogen bonds (in addition to several intercomponent amide-amide hydrogen bonds). Taking advantage of the different hydrogen bonding modes of the sulfur-based functional groups, a switchable molecular shuttle was prepared in which the oxidation level of sulfur determines the position of the macrocycle on the thread.

A natural oil-based emulsion containing allantoin versus aqueous cream for managing radiation-induced skin reactions in patients with cancer : a phase III double-blind randomised controlled trial

Purpose To investigate the effects of a natural oil-based emulsion containing allantoin versus aqueous cream for preventing and managing radiation induced skin reactions (RISR). Methods and Materials A total of 174 patients were randomised and participated in the study. Patients either received Cream 1 (the natural oil-based emulsion containing allantoin) or Cream 2 (aqueous cream). Skin toxicity, pain, itching and skin-related quality of life scores were collected for up to four weeks after radiation treatment. Results Patients who received Cream 1 had a significantly lower average level of Common Toxicity Criteria at week 3 (p<0.05), but had statistically higher average levels of skin toxicity at weeks 7, 8 and 9 (all p<0.001). Similar results were observed when skin toxicity was analysed by grades. With regards to pain, patients in the Cream 2 group had a significantly higher average level of worst pain (p<0.05) and itching (p=0.046) compared to the Cream 1 group at week 3, however these differences were not observed at other weeks. In addition, there was a strong trend for Cream 2 to reduce the incidence of grade 2 or more skin toxicity in comparison to Cream 1 (p=0.056). Overall, more participants in the Cream 1 group were required to use another topical treatment at weeks 8 (p=0.049) and 9 (p=0.01). Conclusion The natural oil-based emulsion containing allantoin appears to have similar effects for managing skin toxicity compared to aqueous cream up to week 5, however, it becomes significantly less effective at later weeks into the radiation treatment and beyond treatment completion (week 6 and beyond). There were no major differences in pain, itching and skin-related quality of life. In light of these results, clinicians and patients can base their decision on costs and preferences. Overall, aqueous cream appears to be a more preferred option.

Qualitative spatial reasoning about directions in a corridor containing a single turn

An experiment was conducted to investigate the process of reasoning about directions in an egocentric space. Each participant walked through a corridor containing an angular turn ranging in size from 0° to 90°, in 15° increments. A direction was given to participants at the entrance of the corridor and they were asked to answer this direction at the end of this corridor. Considering the fact that participants had to reason the direction in the featureless corridor, two hypotheses were proposed: (i) reasoning about directions falls into qualitative reasoning by using a small number of coarse angular categories (four 90° categories or eight 45° categories: 90° categories consist of front, back, left, right; 45° categories consist of 90° categories and the four intermediates) that reference axes generate; (ii) reasoning about directions would be done by recalling the rotation angle from the traveling direction to the direction that participants tried to answer. In addition, the configuration of reference axes that participants employed was examined. Both hypotheses were supported, and the data designated that reference axes consisted of eight directions: a pair of orthogonal axes and diagonals.

A kinetic model for an argon plasma containing dust grains

A complex low-pressure argon discharge plasma containing dust grains is studied using a Boltzmann equation for the electrons and fluid equations for the ions. Local effects, such as the spatial distribution of the dust density and external electric field, are included, and their effect on the electron energy distribution, the electron and ion number densities, the electron temperature, and the dust charge are investigated. It is found that dust particles can strongly affect the plasma parameters by modifying the electron energy distribution, the electron temperature, the creation and loss of plasma particles, as well as the spatial distributions of the electrons and ions. In particular, for sufficiently high grain density and/or size, in a low-pressure argon glow discharge, the Druyvesteyn-like electron distribution in pristine plasmas can become nearly Maxwellian. Electron collection by the dust grains is the main cause for the change in the electron distribution function.

Spectroscopic vibrations of austinite (CaZnAsO4⋅OH) and its mineral structure : Implications for identification of secondary arsenic-containing mineral

Austinite (CaZnAsO4⋅OH) is a unique secondary mineral in arsenic-contaminated mine wastes. The infrared and Raman spectroscopies were used to characterize the austenite vibrations. The IR bands at 369, 790 and 416 cm−1 are assigned to the ν2, ν3 and ν4 vibrations of AsO43− unit, respectively. The Raman bands at 814, 779 and 403 cm−1 correspond to the ν1, ν3 and ν4 vibrations of AsO43− unit respectively. The sharp bands at 3265 cm−1 for IR and 3270 cm−1 both reveals that the structural hydroxyl units exist in the austenite structure. The IR and Raman spectra both show that some SO4 units isomorphically replace AsO4 in austinite. X-ray single crystal diffraction provides the arrangement of each atom in the mineral structure, and also confirms that the conclusions made from the vibrational spectra. Micro-powder diffraction was used to confirm our mineral identification due to the small quantity of the austenite crystals.

Deamplification of pfmdr1-Containing Amplicon on Chromosome 5 in Plasmodium falciparum Is Associated with Reduced Resistance to Artelinic Acid In Vitro

Amplification of the Plasmodium falciparum multidrug resistance 1 gene (pfmdr1) has been implicated in multidrug resistance, including in vitro resistance to artelinic acid (AL). The stability and fitness of having multiple copies of pfmdr1 are important factors due to their potential effects on the resistance phenotype of parasites. These factors were investigated by using an AL-resistant line of P. falciparum (W2AL80) and clones originating from W2AL80. A rapid reduction in pfmdr1 copy number (CN) was observed in the uncloned W2AL80 line; 63% of this population reverted to a CN of <3 without exposure to the drug. Deamplification of the pfmdr1 amplicon was then determined in three clones, each initially containing three copies of pfmdr1. Interestingly, two outcomes were observed during 3 months without drug pressure. In one clone, parasites with fewer than 3 copies of pfmdr1 emerged rapidly. In two other clones, the reversion was significantly delayed. In all subclones, the reduction in pfmdr1 CN involved the deamplification of the entire amplicon (19 genes). Importantly, deamplification of the pfmdr1 amplicon resulted in partial reversal of resistance to AL and increased susceptibility to mefloquine. These results demonstrate that multiple copies of the pfmdr1-containing amplicon in AL-resistant parasites are unstable when drug pressure is withdrawn and have practical implications for the maintenance and spread of parasites resistant to artemisinin derivatives.

A furan-containing conjugated polymer for high mobility ambipolar organic thin film transistors

Furan substituted diketopyrrolopyrrole (DBF) combined with benzothiadiazole based polymer semiconductor PDPP-FBF has been synthesized and evaluated as an ambipolar semiconductor in organic thin-film transistors. Hole and electron mobilities as high as 0.20 cm 2 V -1 s -1 and 0.56 cm 2 V -1 s -1, respectively, are achieved for PDPP-FBF.