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Notes: Background High levels of allergen-specific IgG have been associated with clinical efficacy in immunotherapy studies, but whether this antibody isotype is associated with clinical tolerance in the setting of environmental exposure remains unclear.Objective To determine if mouse allergen-specific IgG (mIgG) and IgG4 (mIgG4) levels are associated with mouse-related symptoms among IgE-sensitized laboratory workers.Methods Fifty-eight workers with either skin test or serologic evidence of IgE-mediated mouse sensitization were studied. Symptom data were obtained by a questionnaire. Serum levels of mouse-specific IgG, IgG4, and IgE were quantified by a solid-phase antigen-binding assay (IgG) and RAST (IgG4 and IgE), and the relationships between mouse-specific serologic responses and mouse-related symptoms were analysed.Results Twenty-three (39.7%) participants reported mouse-related symptoms. Mouse-specific IgG and IgG4 levels were not associated with mouse-related symptoms among the study population as a whole. Among the 29 (50%) participants with detectable mouse-specific IgE (mIgE), higher mouse-specific IgG and IgG4 levels were associated with a decreased risk of symptoms, after adjusting for mIgE level (odds ratio (OR) 0.3, 95% confidence interval (CI): 0.1–1.4, and OR 0.3, 95% CI: 0.04–2.6, respectively). Higher levels of mIgG and mIgG4 remained associated with a decreased risk of symptoms after additional adjustment for sex and handling of mice (OR 0.1, 95% CI: 0.02–0.7, and OR 0.2, 95% CI: 0.02–2.1, respectively). Higher mIgG : IgE and mIgG4 : IgE ratios were also associated with a decreased risk of symptoms after adjusting for these confounders (OR 0.1, 95% CI: 0.02–0.7, and OR 0.2, 95% CI: 0.02–0.92, respectively).Conclusion Among workers with detectable mIgE, higher mIgG and mIgG4 levels are associated with a decreased risk of mouse-related symptoms. High serum levels of mIgG or mIgG4 may be markers for clinical tolerance among laboratory mouse workers with detectable mIgE, but these findings need to be confirmed in larger, prospective studies.

Notes: There has been global neglect of service users’ and carers’ experiences of dementia care provision in rural areas. The present paper draws on a qualitative study of service provision for people with dementia and their carers in remote and rural Scotland. It draws on interviews with 15 people with dementia and 16 carers to explore their views about health and social dementia care service provision in rural Scotland. A further 14 carers of people with dementia participated in one of three focus groups. The paper discusses perceived gaps in services as well as positive aspects of dementia service provision which service users attribute to living in a rural area. The important issues this raises for the development of dementia care provision in rural areas are briefly discussed.

Notes: Bacterivorous protozoa and bacteria have been in co-existence since the origin of life. This co-existence has led unequivocally to the evolution of many different co-interactions. Most bacteria are ingested and digested, but many escape ingestion for various reasons. Others are ingested but evade digestion, and a few, notoriously Legionella pneumophila, even have the capacity of multiplying within the protozoan host. The aims of this study were to elucidate the interactions of various multi-drug-resistant Staphylococcus aureus (MRSA) strains, Listeria monocytogenes sv4b, and Escherichia coli K12 with the amoeba, Acanthamoeba polyphaga. To evaluate the interactions, we set up co-cultures in Neffs' amoebic saline, at a multiplicity of invasion (MOI) of 1:100 of amoeba to bacteria, and a temperature of 37°C, although the effects of MOI and temperature were also assessed. Survival of bacteria and amoeba was checked at regular intervals, coupled with microscopy. It was discovered under our test conditions, that E. coli was ingested and digested by A. polyphaga, but in contrast, L. monocytogenes, had the capacity to flourish in the presence of A. polyphaga. We also report, for the first time, that all six MRSA isolates tested, survived and replicated in association with A. polyphaga, in comparison to conditions where amoebae were absent. Indeed, we also have evidence suggesting that increases in MRSA, in the presence of A. polyphaga, may be attributable to intracellular survival and replication. These findings have profound implications for the hospital environment, where Acanthamoeba sp., are also commonly isolated. In conclusion, this study illustrates the significance of protozoa as vehicles augmenting the survival of MRSA and L. monocytogenes in the environment.

Notes: The microhabitats favoured by protozoa are dynamic ecosystems comprising a heterogeneous microflora of bacteria and fungi as well as protozoa in a complex biofilm. Many protozoa feed by grazing on microbial biofilms, but they do not do so indiscriminately. A dynamic equilibrium will exist and the nature of the relationship changes depending on environmental conditions. The view of protozoa as the hunter and bacteria as the hunted is now recognised as overly simplistic. Some bacteria not only resist predation by protozoa, but also have become endosymbionts of free-living protozoa, demonstrating adaptation to the otherwise hostile intracellular environment. The concept that protozoa can be reservoirs for some pathogens is more widely appreciated and the catalyst for much of this work came from the observation that Legionella pneumophila infects and multiplies within some species of free-living amoebae. In addition to amplifying cell numbers, the phenotype of intra-protozoal-grown cells is quite distinct from their free-living counterparts cultured on complex laboratory media: altered surface properties, decreased susceptibility to chemical inactivation and antibiotics, and enhanced invasiveness for mammalian cells. There is significant conservation in the genes used by L. pneumophila to parasitize protozoa and macrophages and it has been proposed that co-evolution of bacteria and lower order eukaryotic cells has equipped bacteria both for environmental survival and virulence towards higher order eukaryotes. Other authors have even described protozoa as an “evolutionary gym” enabling L. pneumophila to “train” for its role in invading higher eukaryotic organisms.A growing list of bacteria and fungi that interact with protozoa confirm that the co-evolution between L. pneumophila and protozoa is not unique in nature. An emerging theme amongst many of the micro-organisms associating with protozoa is that they typically are recognised as opportunistic pathogens and many lack a recognised animal host. These features are suggestive of a relationship much closer to symbiosis which becomes parasitic only in special circumstances. The question remains why this is so? The answer could lie in co-evolution with lower order eukaryotic organisms present in biofilms.

Notes: In order to be able to monitor dispersion and setting of cements, admixtures can be added, which usually can consist of large organic molecules. Here, the choice is different since small organic molecules have been used as in ceramic processing. This work concerns the preparation of calcium aluminate cement paste in the presence of acetic acid; the water to cement mass ratio is equal to 0.6 and the acid to cement mass ratio, 〈inlineGraphic alt="inline image" href="urn:x-wiley:00027820:JACE00414:JACE_00414_mu15" location="equation/JACE_00414_mu15.gif"/〉 , ranges between 0 and 0.05. This admixture can have either a retarding or an accelerating effect on cement setting. The retarding effect is because of adsorption of acetate complexes, CaCH3CO2+ positively charged, at the surface of CA particles, negatively charged, which leads to the delay (slowing down) of dissolution; it can reach 52 h (case of 〈inlineGraphic alt="inline image" href="urn:x-wiley:00027820:JACE00414:JACE_00414_mu16" location="equation/JACE_00414_mu16.gif"/〉 ). When 〈inlineGraphic alt="inline image" href="urn:x-wiley:00027820:JACE00414:JACE_00414_mu17" location="equation/JACE_00414_mu17.gif"/〉 , there is a remarkable accelerating effect. The setting starts 2 h after mixing the cement with the liquid and is fairly constant for higher acetic acid contents. This rapid setting in acid conditions is because of the formation of hydrated calcium acetate in very low quantities and possibly gibbsite; the setting mechanism is quite different since there is no formation of conventional calcium and aluminum hydrates. As an example, with the highest amount of HOAc ( 〈inlineGraphic alt="inline image" href="urn:x-wiley:00027820:JACE00414:JACE_00414_mu18" location="equation/JACE_00414_mu18.gif"/〉 ), no CxAyHz type of calcium aluminum hydrate is formed after aging for 4 days at 20°C and 95% relative humidity. There is also a densifying effect of acetic acid; the open porosity of set samples left to age for 4 days at 20°C and 95% relative humidity decreases from 35 to 25 vol% when 〈inlineGraphic alt="inline image" href="urn:x-wiley:00027820:JACE00414:JACE_00414_mu19" location="equation/JACE_00414_mu19.gif"/〉 goes from 0 to 0.005 and remains relatively constant afterwards. Lastly, this decrease in the porosity continues with aging time; at 6 months, we obtain values as low as 9 vol% in samples where 〈inlineGraphic alt="inline image" href="urn:x-wiley:00027820:JACE00414:JACE_00414_mu20" location="equation/JACE_00414_mu20.gif"/〉.

Notes: Analysis of medieval luster ceramics seems to indicate that the formation of luster layers could involve an ion exchange between some alkali ions of the glaze (Na+ and K+), and copper and silver cations of the luster raw paint during firing. However, because of the weathering shown by the medieval luster decorations analyzed, conclusive proof is difficult to obtain. A realistic reproduction of the luster decorations has been fabricated in order to follow the process of formation of the luster layer. This has been studied by optical microscopy, transmission electron microscopy, electron probe microanalysis, extended X-ray absorption fine structure, X-ray absorption near-edge structure, and the results give direct evidence that ion exchange and diffusion are the physical–chemical mechanisms responsible for the introduction of copper and silver into the glaze.

Notes: Background  Patients receiving long-term methotrexate for psoriasis are at risk of developing hepatic fibrosis. Repeated liver biopsy has long been regarded as the only reliable method of detecting this and it is still recommended by the American Academy of Dermatology (AAD). More recently, monitoring by serum procollagen III aminopeptide (PIIINP) measurement (Orion Diagnostica, Espoo, Finland) has been advocated as a means of significantly reducing the need for liver biopsy.Objectives  To assess the validity of guidelines developed in Manchester for the use of PIIINP to monitor patients with psoriasis receiving long-term methotrexate; to assess the anticipated benefits to patients of introducing this change in practice, including reduction in requirement for liver biopsy; and to determine the impact of its introduction on healthcare costs.Methods  A multicentre audit was conducted over a 24-month period to compare the healthcare costs and outcomes of two intervention groups from centres where serial PIIINP measurement was employed with those of two control groups from centres in which AAD guidelines were followed.Results  A sevenfold reduction in the need for liver biopsy was observed in the two intervention groups (n = 166; 0·04 and 0·02 biopsies/patient/year, respectively) compared with the two control groups (n = 87; 0·26 and 0·30 biopsies/patient/year, respectively). Abnormalities of sufficient severity to influence management were identified in one in five patients biopsied in the main intervention group compared with one in 16 in the control groups. The overwhelming majority of patients surveyed expressed a preference for being monitored by methods that would minimize the need for liver biopsy. The adoption of PIIINP for monitoring would result in significant cost savings.Conclusions  This audit has shown that patients managed by the Manchester protocol using serial PIIINP measurement and selective liver biopsy were not disadvantaged in comparison with those managed according to AAD guidelines; they were subjected to sevenfold fewer liver biopsies without evidence that important liver toxicity was missed in the process. If PIIINP monitoring were widely adopted, methotrexate would become a more acceptable option for many patients who are dissuaded from considering it because of the threat of repeated liver biopsy; it would also result in significant savings to the healthcare budget.