Publications by authors named "Postma P"

Introduction: Nosocomial structures pose a high risk of . contamination due to complex water systems with challenging disinfection; moreover, the risk of severe legionellosis as a consequence of nosocomial exposure is very high in settings characterized by vulnerable patient conditions.

Methods: In the present work, we described the results of 7 years of environmental surveillance in a reference hospital in Liguria, in which a specific water safety plan (WSP) has been implemented in 2017, including data collected during the COVID-19 pandemic.

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Background: Reducing the number of animals used in experiments has become a priority for the governments of many countries. For these reductions to occur, animal-free alternatives must be made more available and, crucially, must be embraced by researchers.

Methods: We conducted an international online survey for academics in the field of animal science ( = 367) to explore researchers' attitudes towards the implementation of animal-free innovations.

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The effect of osmotic shock, enzymatic incubation, pulsed electric field, and high shear homogenization on the release of water-soluble proteins and carbohydrates from the green alga was investigated in this screening study. For osmotic shock, both temperature and incubation time had a significant influence on the release with an optimum at 30 °C for 24 h of incubation. For enzymatic incubation, pectinase demonstrated being the most promising enzyme for both protein and carbohydrate release.

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The disintegration of three industry relevant algae (Chlorella vulgaris, Neochloris oleoabundans and Tetraselmis suecica) was studied in a lab scale bead mill at different bead sizes (0.3-1mm). Cell disintegration, proteins and carbohydrates released into the water phase followed a first order kinetics.

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The synergistic effect of temperature (25-65 °C) and total specific energy input (0.55-1.11 kWh kgDW(-1)) by pulsed electric field (PEF) on the release of intracellular components from the microalgae Chlorella vulgaris was studied.

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In this work, the mild disintegration of the microalgae Chlorella vulgaris for the release of intracellular products has been studied. By means of bead milling the microalgae suspensions were successfully disintegrated at different biomass concentrations (25-145 gDW kg(-1)) over a range of agitator speeds (6-12 m s(-1)). In all cases over 97% of cell disintegration was achieved resulting in a release of water soluble proteins.

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Cellular systems are essential model systems to study reactive oxygen species and oxidative damage but there are widely accepted technical difficulties with available methods for quantifying endogenous oxidative damage in these systems. Here we present a stable isotope dilution UPLC-MS/MS protocol for measuring F2-isoprostanes as accurate markers for endogenous oxidative damage in cellular systems. F2-isoprostanes are chemically stable prostaglandin-like lipid peroxidation products of arachidonic acid, the predominant polyunsaturated fatty acid in mammalian cells.

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Background And Objectives: Distressing intrusions are a hallmark of posttraumatic stress disorder (PTSD). Dysfunctional appraisal of these symptoms may exacerbate the disorder, and conversely may lead to further intrusive memories. This raises the intriguing possibility that learning to 'reappraise' potential symptoms more functionally may protect against such symptoms.

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This research is legislation driven by the European Water Framework Directive (WFD) and the Dutch Fourth Memorandum on Water Management. The objective of this research is to achieve the removal of total nitrogen and total phosphorus by Dual Media Filtration. The target value during this research for total nitrogen is 2.

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The types of appraisals that follow traumatic experiences have been linked to the emergence of posttraumatic stress disorder (PTSD). Could changing reappraisals following a stressful event reduce the emergence of PTSD symptoms? The present proof-of-principle study examined whether a nonexplicit, systematic computerized training in reappraisal style following a stressful event (a highly distressing film) could reduce intrusive memories of the film, and symptoms associated with posttraumatic distress over the subsequent week. Participants were trained to adopt a generally positive or negative poststressor appraisal style using a series of scripted vignettes after having been exposed to highly distressing film clips.

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Modifying substrate uptake systems is a potentially powerful tool in metabolic engineering. This research investigates energetic and metabolic changes brought about by the genetic modification of the glucose uptake and phosphorylation system of Escherichia coli. The engineered strain PPA316, which lacks the E.

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During Escherichia coli growth on glucose, uptake exceeds the requirement of flux to precursors and the surplus is excreted as acetate. Beside the loss of carbon source, the excretion of a weak acid may result in increased energetic demands and hence a decreased yield. The deletion of ptsG, the gene coding for one of the components (IICB(Glc)) of the glucose-phosphoenolpyruvate phosphotransferase system (Glc-PTS) reduced glucose consumption and acetate excretion.

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The phosphoenolpyruvate(PEP):carbohydrate phosphotransferase system (PTS) is found only in bacteria, where it catalyzes the transport and phosphorylation of numerous monosaccharides, disaccharides, amino sugars, polyols, and other sugar derivatives. To carry out its catalytic function in sugar transport and phosphorylation, the PTS uses PEP as an energy source and phosphoryl donor. The phosphoryl group of PEP is usually transferred via four distinct proteins (domains) to the transported sugar bound to the respective membrane component(s) (EIIC and EIID) of the PTS.

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Although damage to right posterior parietal cortex (RPPC) produces bias in line bisection, Karnath et al. [Karnath, H.-O.

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Rationale: Schizophrenia patients display an excessive rate of smoking compared to the general population. Nicotine increases acoustic prepulse inhibition (PPI) in animals as well as healthy humans, suggesting that smoking may provide a way of restoring deficient sensorimotor gating in schizophrenia. No previous study has examined the neural mechanisms of the effect of nicotine on PPI in humans.

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A previous paper reported high susceptibility to spatial migration (allochiria) of tactile stimuli in about 25% of healthy individuals (High Error subjects). When synchronous stimuli touched the two hands, if the unattended stimulus was temporally modulated when the attended one was not (and was thus more salient than the latter), it "migrated" to and fused with or replaced the stimulus on the attended hand. When subjects rated similarity of the attended stimulus accompanied by a distractor to each stimulus alone, scaling distributions tested against a sampling model showed most High Error subjects experienced fused stimuli, others experienced replacement and Low Error subjects experienced neither.

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The behavioural and cognitive effects of nicotine in schizophrenia have received much interest in recent years. The rate of smoking in patients with schizophrenia is estimated to be two- to four-fold the rate seen in the general population. Furthermore such patients favour stronger cigarettes and may also extract more nicotine from their cigarettes than other smokers.

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Although glucose is an inexpensive substrate widely used as a carbon source in Escherichia coli recombinant fermentation technology, 10-30% of the carbon supply is wasted by excreting acetate. In addition to the loss of carbon source, the excretion of a weak acid may result in increased energetic demands and hence a decreased yield. Because glucose can enter the cell via several transport systems, isogenic strains defective in one or two of these transport systems were constructed.

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Migration of tactile sensation was found to occur very frequently in about 25% of normal people (High Error subjects) and very infrequently in others. When synchronous stimuli touched the two hands, if the unattended stimulus was modulated when the attended one was not (and was thus more salient) it "migrated" to the attended hand and fused with or replaced the attended stimulus. However, latencies reflecting congruence and incongruence of simultaneous stimuli showed that their identities on each hand had been (nonconsciously) registered veridically.

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We calculated the implications of diffusion for the phosphoenolpyruvate:glucose phosphotransferase system (glucose-PTS) of Escherichia coli in silicon cells of various magnitudes. For a cell of bacterial size, diffusion limitation of glucose influx was negligible. Nevertheless, a significant concentration gradient for one of the enzyme species, nonphosphorylated IIA(Glc), was found.

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Fed-batch production of recombinant beta-galactosidase in E. coli was studied with respect to the specific growth rate at induction. The cultivations were designed to induce protein production by IPTG at a glucose feed rate corresponding to high mu = 0.

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Deletions were made in Streptomyces lividans in either of two genes (zwf1 and zwf2) encoding isozymes of glucose-6-phosphate dehydrogenase, the first enzyme in the oxidative pentose phosphate pathway (PPP). Each mutation reduced the level of Zwf activity to approximately one-half that observed in the wild-type strain. When the mutants were transformed with multicopy plasmids carrying the pathway-specific transcriptional activator genes for either the actinorhodin (ACT) or undecylprodigiosin (RED) biosynthetic pathway, they produced higher levels of antibiotic than the corresponding wild-type control strains.

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The UhpABC regulatory system in enterobacteria controls the expression of the hexose phosphate transporter UhpT. Signaling is initiated through sensing of extracellular glucose 6-phosphate by membrane-bound UhpC, which in turn modulates the histidine-protein kinase UhpB. Together with the cytoplasmic response regulator UhpA, they constitute a typical two-component regulatory system based on His-to-Asp phosphoryl transfer.

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The carbon metabolism of derivatives of Streptomyces lividans growing under phosphate limitation in chemostat cultures and producing the antibiotics actinorhodin and undecylprodigiosin was investigated. By applying metabolic flux analysis to a stoichiometric model, the relationship between antibiotic production, biomass accumulation, and carbon flux through the major carbon metabolic pathways (the Embden Meyerhoff Parnas and pentose-phosphate pathways) was analyzed. Distribution of carbon flux through the catabolic pathways was shown to be dependent on growth rate, as well as on the carbon and energy source (glucose or gluconate) used.

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The formation of glycerol-3-phosphate (G3P) in cells growing on TB causes catabolite repression, as shown by the reduction in malT expression. For this repression to occur, the general proteins of the phosphoenolpyruvate-dependent phosphotransferase system (PTS), in particular EIIA(Glc), as well as the adenylate cyclase and the cyclic AMP-catabolite activator protein system, have to be present. We followed the level of EIIA(Glc) phosphorylation after the addition of glycerol or G3P.

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