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Duurzame ontwikkeling en mensenrechten zijn twee kanten van dezelfde medaille. De Nederlandse mensenrechteninzet en het beleid voor duurzame ontwikkeling moeten daarom scherp op elkaar worden afgestemd. De duurzame ontwikkelingsdoelen (Sustainable Development Goals of SDG’s) van de Verenigde Naties bieden een bruikbaar handvat. Het internationale bedrijfsleven en maatschappelijke organisaties spelen daarin een sleutelrol.

Met lit. opg

Lit.opg.

Projectcode: 07HKG

The osmosensing mechanism of the ATP-binding cassette (ABC) transporter OpuA of Lactococcus lactis has been elucidated for the protein reconstituted in liposomes. Activation of OpuA by osmotic upshift was instantaneous and reversible and followed changes in volume and membrane structure of the proteoliposomes. Osmotic activation of OpuA was dependent on the fraction of anionic lipids present in the lipid bilayer. Also, cationic and anionic lipophilic amphiphiles shifted the activation profile in a manner indicative of an osmosensing mechanism, in which electrostatic interactions between lipid headgroups and the OpuA protein play a major role. Further support for this notion came from experiments in which ATP-driven uptake and substrate-dependent ATP hydrolysis were measured with varying concentrations of osmolytes at the cytoplasmic face of the protein. Under iso-osmotic conditions, the transporter could be activated by high concentrations of ionic osmolytes, whereas neutral ones had no effect, demonstrating that intracellular ionic strength, rather than a specific signaling molecule or water activity, signals osmotic stress to the transporter. The data indicate that OpuA is under the control of a mechanism in which the membrane and ionic strength act in concert to signal osmotic changes.

The aggregation behavior of a series of alkyltrimethylammonium 5-ethylsalicylate surfactants (CnTA5ES, n = 12, 14, 16) in aqueous solution has been investigated employing turbidity measurements, fluorescence anisotropy experiments (using 3-hydroxynaphthalene-2-carboxylate, HNC-), and cryo transmission electron microscopy (cryo TEM). Critical aggregation concentrations (cac) were determined by surface tension experiments; they are smaller than those of their salicylate analogues. CnTA5ES surfactants form vesicles immediately above the cac rather than wormlike micelles such as their salicylate counterparts. C12TA5ES was found to form large unilamellar vesicles (LUVs) which transformed into surfactant layers upon increasing surfactant concentration. The transition was characterized by an increase in turbidity. C14TA5ES and C16TA5ES were found to form LUVs and long wormlike vesicles which are assumed to be responsible for the viscoelasticity of the solutions. Upon increase of the surfactant concentration, a t...

Met lit. opg

Lit.opg., bijl.

Opdrachtgever: Gemeente Almere, DSO

ill

Opdrachtgever: Gemeente Almere, DSO

DSC scans for vesicles in aqueous systems produced by mixtures of dihexadecyldimethylammonium (DHAB where R = C16H33 in R2N+Me2Br−) and dioctadecyldimethylammonium bromides (DOAB where R = C18H37 in R2N+Me2Br−) show for most mixtures two melting points corresponding to gel to liquid-crystal transitions which depend on the composition of the vesicular system. The gel to liquid-crystal transitions occur over a wider temperature range than for vesicular systems prepared using a single dialkyldimethylammonium surfactant. The resulting temperature-mole fraction diagram is similar to that observed for continuous solid solutions. The overall pattern shows that in a given solution two types of domains in the vesicular bilayer systems can co-exist having slightly different compositions and hence melting temperatures.

Lit.opg. en verklarende woordenlijst.

Lit.opg. en verklarende woordenlijst.

Lit.opg. en verklarende woordenlijst.

Lit.opg. en verklarende woordenlijst.

Lit.opg. en verklarende woordenlijst.

Lit.opg. en verklarende woordenlijst.

Lit.opg.

Doel Bepalen welke ‘extended’-spectrum-bètalactamase(ESBL)-genen en plasmiden aanwezig zijn in Escherichia coli in vleeskuikens en vers kippenvlees uit Nederland en tevens in een voor Nederland representatieve collectie van klinische E. coli isolaten van patiënten. Opzet Beschrijvend. Methoden ESBL-producerende E. coli-isolaten waren afkomstig van 98 kipfilets, een ESBL-surveillance studie bij vleeskuikens uit 2006 en 516 humane klinische isolaten uit 31 laboratoria verzameld gedurende een periode van 3 maanden in 2009. De distributie werd vastgesteld van ESBL-genen en plasmiden in E. coli aanwezig in vleeskuikens en vers kippenvlees en de gevonden ESBL-genen werden gedefinieerd als ‘kip-geassocieerd’. In een voor Nederland representatieve steekproef van klinische E. coli-isolaten werd het aandeel van kip-geassocieerde ESBL-genen en plasmiden gekwantificeerd. De isolaten werden geanalyseerd met een ESBL-specifieke microarray, een ESBL-gensequentiebepaling, en 2 plasmide-typeringsmethoden: zogenaamde PCR-gebaseerde replicon-typering en plasmide-multi-locussequentietypering. Resultaten 6 ESBL-genen werden aangemerkt als ‘kip-geassocieerd’: bla CTXM-1, bla CTXM-2, bla SHV-2, bla SHV-12, bla TEM-20, bla TEM-52. Van de humane ESBL-producerende isolaten bevatte 35% een kip-geassocieerd ESBL-gen, en 19% een kip-geassocieerd ESBL-gen gelegen op een IncI1-plasmide, dat genetisch niet te onderscheiden was van plasmides afkomstig van vleeskuikens. In humane isolaten met een kip-geassocieerde ESBL’s waren bla CTXM-1 en bla TEM-52 de meest prevalente ESBL-genen (86%), net als in de isolaten van vleeskuikens (78%) en kipfilets (75%). Van de 98 kipfilets bevatte 94% een ESBL producerende E. coli. Conclusie Deze bevindingen zijn suggestief voor overdracht van ESBL producerende E. coli van pluimvee naar de mens via de voedselketen.

This is the first report of 3 patients in whom carbapenemase-producing Klebsiella pneumoniae was identified in the Netherlands following foreign travel. They were a 55-year-old man who had undergone chemotherapy for lung cancer metastases, a 66-year-old woman and a 30-year-old man. The first patient was transferred from a Greek hospital; his isolate belonged to an epidemic clone (multilocus sequence type 258) with a KPC-2 carbapenemase gene. The patient died from pneumonia. The other two patients, who had been travelling around in India, were found to be colonised in the gasto-intestinal tract with different multiresistant K. pneumoniae isolates containing a New Delhi metallo-carbapenemase gene (NDM-1). The rapid emergence and dissemination of Enterobacteriaceae resistant to carbapenems such as imipenem and meropenem poses a considerable threat to clinical patient care and public health. Carbapenemase-producing strains are characterized by resistance to nearly all available beta-lactam antibiotics including cephalosporins and carbapenems. These strains are often also resistant to other classes of antibiotics. Invasive infections by these strains are associated with high morbidity and mortality rates. Adequate microbiological laboratory detection and infection control measures in hospital are pivotal to preventing dissemination in the Dutch healthcare setting.