There is much interest in attaching polyethylene glycol (PEG) and other hydrophilic, neutral polymers to surfaces to reduce the extent of protein and cell adsorption. Interestingly, these same surface-bound polymers are effective in masking surface charge and reducing electrokinetic effects such as particle electrophoretic mobility, streaming potential, and electroosmosis. It is apparent that similar molecular properties are responsible for both protein and cell rejection and reduction of electrokinetic effects. In this work we compared the fibrinogen-rejecting ability and the effect on electrophoretic mobility of three polymer coatings bound to polystyrene. The three polymers were side-bound dextran, end-bound dextran, and end-bound PEG. The results of these measurements were used to elucidate the importance of polymer packing density and polymer layer thickness on protein adsorption and reduction of electrokinetic effects. Protein adsorption appears not to be sensitive to polymer layer thickness or the presence of dilute polymer tails in a surface coating, while electrokinetic effects are. Protein adsorption is, however, very sensitive to the availability of exposed surface. Finally, the unique effectiveness of PEG is apparent in this research as in previous studies.

In the context of the Millennium Development Goals, human resources represent the most critical constraint in achieving the targets. Therefore, it is important for health planners and decision-makers to identify what are the human resources required to meet those targets. Planning the human resources for health is a complex process. It needs to consider both the technical aspects related to estimating the number, skills and distribution of health personnel for meeting population health needs, and the political implications, values and choices that health policy- and decision-makers need to make within given resources limitations. After presenting an overview of the various methods for planning human resources for health, with their advantages and limitations, this paper proposes a methodological approach to estimating the requirements of human resources to achieve the goals set forth by the Millennium Declaration. The method builds on the service-target approach and functional job analysis.

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Reduction of protein adsorption by coating surfaces with polyethylene glycol (PEG) is well documented. The present work has four goals related to these previous studies: first, to develop chemistry providing densely packed, covalently bound PEG on polystyrene (PS); second, to determine the ability of these modified surfaces to reject fibrinogen; third, to compare the protein-rejecting ability of branched and linear PEGs; and fourth, to examine the utility of an ELISA-type procedure for measuring protein adsorption. It was found that PEG-epoxide could be readily coupled to amine groups of poly(ethylene imine) (PEI), which had been preadsorbed onto an oxidized PS surface. The PEG groups on branched PEGs appear to act as an excluded volume to repel proteins, similar to arguments previously raised for linear PEGs. The results of protein adsorption studies showed that fibrinogen adsorption is significantly reduced by coating polystyrene with either linear or branched PEGs of 1500 to 20,000 in molecular weight. The ELISA technique was found to be equivalent in sensitivity to radiolabeled fibrinogen for estimating adsorption levels. It is expected that PEG-coated PS will have much utility in a variety of biomedical applications.

BackgroundThere is a growing concern regarding the increase of antimicrobial resistant bacteria in companion animals. Yet, there are no studies comparing the resistance levels of these organisms in European countries. The aim of this study was to investigate geographical and temporal trends of antimicrobial resistant bacteria causing urinary tract infection (UTI) in companion animals in Europe. The antimicrobial susceptibility of 22 256 bacteria isolated from dogs and cats with UTI was determined. Samples were collected between 2008 and 2013 from 16 laboratories of 14 European countries. The prevalence of antimicrobial resistance of the most common bacteria was determined for each country individually in the years 2012–2013 and temporal trends of bacteria resistance were established by logistic regression.ResultsThe aetiology of uropathogenic bacteria differed between dogs and cats. For all bacterial species, Southern countries generally presented higher levels of antimicrobial resistance compared to Northern countries. Multidrug-resistant Escherichia coli were found to be more prevalent in Southern countries. During the study period, the level of fluoroquinolone-resistant E. coli isolated in Belgium, Denmark, France and the Netherlands decreased significantly. A temporal increase in resistance to amoxicillin-clavulanate and gentamicin was observed among E. coli isolates from the Netherlands and Switzerland, respectively. Other country-specific temporal increases were observed for fluoroquinolone-resistant Proteus spp. isolated from companion animals from Belgium.ConclusionsThis work brings new insights into the current status of antimicrobial resistance in bacteria isolated from companion animals with UTI in Europe and reinforces the need for strategies aiming to reduce resistance.

A total of 41 blood samples were collected from 40 Anaplasma phagocytophila-infected sheep in 11 sheep flocks from four different counties of southern Norway. The presence and nature of the Anaplasma species were identified by microscopic detection of morulae, PCR, reverse line blot hybridization, and 16S rRNA gene sequencing. A. phagocytophila was identified in all of the samples, and sequencing of the 16S rRNA gene revealed the presence of four variants of A. phagocytophila. Two of these variants have been described before, but two were newly identified 16S rRNA variants of this species. A. phagocytophila variant 1 was found in nine flocks, A. phagocytophila variant 2 was found in four flocks, the A. phagocytophila prototype was found in two flocks, and A. phagocytophila variant 5 was found in one flock. In two flocks, some sheep were infected with A. phagocytophila variant 1, whereas others were infected with A. phagocytophila variant 2, and in three animals a double infection with two variants was registered. Analyses of the blood samples revealed that blood from sheep infected with A. phagocytophila variant 2 contained nearly twice as many neutrophils and eight times as many Anaplasma-infected neutrophils as blood from sheep infected with the A. phagocytophila variant 1. Furthermore, only 43% of the A. phagocytophila variant 2-infected sheep displayed antibody responses in an immune fluorescence assay, whereas 93% of the sheep with the A. phagocytophila variant 1-infected sheep were seropositive.

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Cleavable surfactants are of interest for several reasons. Above all, the development of surfactants with weak bonds deliberately built into the structure is driven by the need for improved biodegradability of amphiphiles. The breakdown may be catalyzed by enzymes, and biodegradation would be the normal mechanism in sewage plants. Alternatively, the surfactant may degrade by chemical means, e.g., induced by acid, alkali, ultraviolet (UV) light, heat, or ozone. Acid-and alkali-labile surfactants have attracted particular attention, and there is often a compromise between required stability at one stage and ease of breakdown at a subsequent stage. The paper reviews the main routes used to prepare cleavable surfactants and points out advantages and disadvantages of the different approaches. Emphasis is placed on the development during recent years. Cyclic and acyclic acetals, ketals, and ortho esters are the most important types of bonds for the preparation of acid-labile surfactants, whereas alkali-labile amphiphiles usually are based on ester bonds. The ester bond approach has been particularly important for cationic surfactants, and so-called ester quats have rapidly taken a large share of the traditional market for quats. Betaine esters constitute a special class of ester with very pronounced pH dependence. UV-labile surfactants based, for instance, on an azo bond, offer promise for the future.Paper no. S1174 in JSD 3, 81-91 (January 2000). KEY WORDS: Acetal, betaine ester, choline ester, cleavable surfactant, ester quat, isethionate ester, ketal, labile surfactant, ortho ester, UV degradation. SCHEME 17 SCHEME 16amples of environmentally benign amphiphiles. These surfactants, which contain unsaturated bonds, break down easily during ozonization of water, which is a water purification process of growing importance (64).