2,700 research outputs found

    Investigating processing window of Affinisol™ and Plasdone™ - S630 polymers during hot-melt extrusion (for 3D printing by fused deposition modelling)

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    There are numerous polymers that have been used commercially to produce pharmaceutical solid dispersions and solutions from hot melt extrusion. Affinisol™ (HPMC) and Plasdone™ S630 (PVP based co-povidone copolymer) have been used in the present work to determine the viable processing space with regards thermal and work input on a twin screw extruder. Processing viability has been determined by monitoring degradation, initially assessed by physical appearance and colour of the extrudates across the full operating range of a twin screw extruder. It has been found that the Affinisol™ had a relatively narrow viable operating window compared with the Plasdone™

    Nurses\u27 Alumnae Association Bulletin, June 1969

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    Alumnae President\u27s Message Officers and Chairmen Financial Report Progressive Changes at Jefferson School of Nursing Report Student Activities School of Practical Nursing Report Jefferson Expansion Report Clerk-Typist Report Committee Reports Resume of Alumnae Meetings Class News 1969 CLINIC Correspondence Notice

    Interactions between Magnetic Nanowires and Living Cells : Uptake, Toxicity and Degradation

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    We report on the uptake, toxicity and degradation of magnetic nanowires by NIH/3T3 mouse fibroblasts. Magnetic nanowires of diameters 200 nm and lengths comprised between 1 {\mu}m and 40 {\mu}m are fabricated by controlled assembly of iron oxide ({\gamma}-Fe2O3) nanoparticles. Using optical and electron microscopy, we show that after 24 h incubation the wires are internalized by the cells and located either in membrane-bound compartments or dispersed in the cytosol. Using fluorescence microscopy, the membrane-bound compartments were identified as late endosomal/lysosomal endosomes labeled with lysosomal associated membrane protein (Lamp1). Toxicity assays evaluating the mitochondrial activity, cell proliferation and production of reactive oxygen species show that the wires do not display acute short-term (< 100 h) toxicity towards the cells. Interestingly, the cells are able to degrade the wires and to transform them into smaller aggregates, even in short time periods (days). This degradation is likely to occur as a consequence of the internal structure of the wires, which is that of a non-covalently bound aggregate. We anticipate that this degradation should prevent long-term asbestos-like toxicity effects related to high aspect ratio morphologies and that these wires represent a promising class of nanomaterials for cell manipulation and microrheology.Comment: 21 pages 12 figure

    Portugal e os BRIC: numa perspectiva da diplomacia pública e da autopoiesis

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    O sistema internacional post-­‐11 de Setembro vem acelerar a movimentação em torno da sociedade civil, alterando, consequentemente, o próprio conceito espácio-­temporal da actuação da diplomacia, na sua acepção clássica, na arena internacional enquanto instrumento pacífico de execução da política externa. Assiste-se a uma complexidade crescente no processo de edificação da nova ordem mundial cujo epicentro se circunscreve numa espécie de sub-­‐mundialização à escala doméstica de cada Estado quer pela (in)capacidade da elite governante em responder aos estímulos provenientes do ambiente externo ao ritmo vertiginoso da velocidade dos fluxos de informação entre os mais diversos actores das relações internacionais. Daí que a prática da diplomacia tradicional tal como a conhecemos caminha para além da evolução teórica, situando-­se cada vez mais em termos concretos num mundo inconstante de caminho incerto com regimes antagónicos de convergências pontuais e imprevisíveis que levam à emergência de outras formas de actuação como sendo o caso da diplomacia pública que representa um recurso estratégico vital para os estados enquanto actores das relações internacionais e concretamente para o caso de Portugal nas suas relações com os BRIC onde se pretende melhorar e influenciar a imagem de um país quer internamente quer externamente como um país/marca num mundo competitivo

    A Comparison of Computerized Chemical Models for Equilibrium Calculations in Aqueous Systems

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    A survey of computer programs which are currently being used to calculate the distribution of species in aqueous solutions, especially natural waters, has been made in order to 1) provide an inventory of available programs with a short description of their uses, 2) compare the consistency of their output for two given test solutions and 3) identify major weaknesses or problems encountered from their use. More than a dozen active programs which can be used for distribution of species and activity calculations for homogeneos equilibria among the major anions and cations of natural waters have been inventoried. Half of these programs can also accept several trace elements including Fe, Al, Mn, Cu, Ni, Zn, Cd, Pb, Ag, Hg, As, Ba, Sr, and B. Consistency between programs was evaluated by comparing the log of the molal concentrations of free ions and complexes for two test solutions: a hypothetical seawater analysis and a hypothetical river water analysis. Comparison of the free major ion concentrations in the river water test case shows excellent agreement for the major species. In the seawater test case there is less agreement and for both test cases the minor species commonly show orders of magnitude differences in concentrations. These differences primarily reflect differences in the thermodynamic data base of each chemical model although other factors such as activity coefficient calculations, redox assumptions, temperature corrections, alkalinity corrections and the number of complexes used all have an affect on the output

    Design and Synthesis of Broad Spectrum Trypanosomatid Selective Inhibitors

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    Neglected tropical diseases caused by parasitic infections are an ongoing and increasing concern that have a devastating effect on the developing world due to their burden on human and animal health. In this work, we detail the preparation of a focused library of substituted-tetrahydropyran derivatives and their evaluation as selective chemical tools for trypanosomatid inhibition and the follow-on development of photoaffinity probes capable of labeling target protein(s) <i>in vitro</i>. Several of these functionalized compounds maintain low micromolar activity against <i>Trypanosoma brucei</i>, <i>Trypanosoma cruzi</i>, <i>Leishmania major</i>, and <i>Leishmania donovani</i>. In addition, we demonstrate the utility of the photoaffinity probes for target identification through preliminary cellular localization studies

    Actinopolyspora algeriensis sp. nov., a novel halophilic actinomycete isolated from a Saharan soil

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    A halophilic actinomycete strain designated H19T, was isolated from a Saharan soil in the Bamendil region (Ouargla province, South Algeria) and was characterized taxonomically by using a polyphasic approach. The morphological and chemotaxonomic characteristics of the strain were consistent with those of members of the genus Actinopolyspora, and 16S rRNA gene sequence analysis confirmed that strain H19T was a novel species of the genus Actinopolyspora. DNA–DNA hybridization value between strain H19T and the nearest Actinopolyspora species, A. halophila, was clearly below the 70 % threshold. The genotypic and phenotypic data showed that the organism represents a novel species of the genus Actinopolyspora for which the name Actinopolyspora algeriensis sp. nov. is proposed, with the type strain H19T (= DSM 45476T = CCUG 62415T)

    Individual variation in levels of haptoglobin-related protein in children from Gabon

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    Background: Haptoglobin related protein (Hpr) is a key component of trypanosome lytic factors (TLF), a subset of highdensity lipoproteins (HDL) that form the first line of human defence against African trypanosomes. Hpr, like haptoglobin (Hp) can bind to hemoglobin (Hb) and it is the Hpr-Hb complexes which bind to these parasites allowing uptake of TLF. This unique form of innate immunity is primate-specific. To date, there have been no population studies of plasma levels of Hpr, particularly in relation to hemolysis and a high prevalence of ahaptoglobinemia as found in malaria endemic areas. Methods and Principal Findings: We developed a specific enzyme-linked immunosorbent assay to measure levels of plasma Hpr in Gabonese children sampled during a period of seasonal malaria transmission when acute phase responses (APR), malaria infection and associated hemolysis were prevalent. Median Hpr concentration was 0.28 mg/ml (range 0.03-1.1). This was 5-fold higher than that found in Caucasian children (0.049 mg/ml, range 0.002-0.26) with no evidence of an APR. A general linear model was used to investigate associations between Hpr levels, host polymorphisms, parasitological factors and the acute phase proteins, Hp, C-reactive protein (CRP) and albumin. Levels of Hpr were associated with Hp genotype, decreased with age and were higher in females. Hpr concentration was strongly correlated with that of Hp, but not CRP

    Multi-omics subgroups associated with glycaemic deterioration in type 2 diabetes:an IMI-RHAPSODY Study

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    Introduction: Type 2 diabetes (T2D) onset, progression and outcomes differ substantially between individuals. Multi-omics analyses may allow a deeper understanding of these differences and ultimately facilitate personalised treatments. Here, in an unsupervised “bottom-up” approach, we attempt to group T2D patients based solely on -omics data generated from plasma. Methods: Circulating plasma lipidomic and proteomic data from two independent clinical cohorts, Hoorn Diabetes Care System (DCS) and Genetics of Diabetes Audit and Research in Tayside Scotland (GoDARTS), were analysed using Similarity Network Fusion. The resulting patient network was analysed with Logistic and Cox regression modelling to explore relationships between plasma -omic profiles and clinical characteristics. Results: From a total of 1,134 subjects in the two cohorts, levels of 180 circulating plasma lipids and 1195 proteins were used to separate patients into two subgroups. These differed in terms of glycaemic deterioration (Hazard Ratio=0.56;0.73), insulin sensitivity and secretion (C-peptide, p=3.7e-11;2.5e-06, DCS and GoDARTS, respectively; Homeostatic model assessment 2 (HOMA2)-B; -IR; -S, p=0.0008;4.2e-11;1.1e-09, only in DCS). The main molecular signatures separating the two groups included triacylglycerols, sphingomyelin, testican-1 and interleukin 18 receptor. Conclusions: Using an unsupervised network-based fusion method on plasma lipidomics and proteomics data from two independent cohorts, we were able to identify two subgroups of T2D patients differing in terms of disease severity. The molecular signatures identified within these subgroups provide insights into disease mechanisms and possibly new prognostic markers for T2D.</p
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