Mucosal Immunity and Candida albicans Infection

Interactions between mucosal surfaces and microbial microbiota are key to host defense, health, and disease. These surfaces are exposed to high numbers of microbes and must be capable of distinguishing between those that are beneficial or avirulent and those that will invade and cause disease. Our understanding of the mechanisms involved in these discriminatory processes has recently begun to expand as new studies bring to light the importance of epithelial cells and novel immune cell subsets such as Th17 T cells in these processes. Elucidating how these mechanisms function will improve our understanding of many diverse diseases and improve our ability to treat patients suffering from these conditions. In our voyage to discover these mechanisms, mucosal interactions with opportunistic commensal organisms such as the fungus Candida albicans provide insights that are invaluable. Here, we review current knowledge of the interactions between C. albicans and epithelial surfaces and how this may shape our understanding of microbial-mucosal interactions

Interannual variation in seasonal drivers of soil respiration in a semi-arid Rocky Mountain meadow

pre-printSemi-arid ecosystems with annual moisture inputs dominated by snowmelt cover much of the western United States, and a better understanding of their seasonal drivers of soil respiration is needed to predict consequences of climatic change on soil CO2 efflux. We assessed the relative importance of temperature, moisture, and plant phenology on soil respiration during seasonal shifts between cold, wet winters and hot, dry summers in a Rocky Mountain meadow over 3.5 separate growing seasons. We found a consistent, unique pattern of seasonal hysteresis in the annual relationship between soil respiration and temperature, likely representative for this ecosystem type, and driven by (1) continued increase in soil T after summer senescence of vegetation, and (2) reduced soil respiration during cold, wet periods at the beginning versus end of the growing season. The timing of meadow senescence varied between years with amount of cold season precipitation, but on average occurred days before soil temperature peaked in late-summer. Autumn soil respiration was greatest when substantial autumn precipitation events occurred early. Surface CO2 efflux was temporarily decoupled from respiratory production during winter 2006/2007, due to effects of winter surface snow and ice on mediating the diffusion of CO2 from deep soil horizons to the atmosphere. Upon melt of a capping surface ice layer, release of soil-stored CO2 was determined to be 65 g C, or *10 % of the total growing season soil respiration for that year. The shift between soil respiration sources arising from moisture-limited spring plant growth and autumn decomposition indicates that annual mineralization of soil carbon will be less dependent on projected changes in temperature than on future variations in amount and timing of precipitation for this site and similar semiarid ecosystems

Early and late scavenging of anaesthetic gases

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Comparison of three anaesthetic scavenging devices using cuffed and non-cuffed nasal endotracheal tubes during dental anaesthesia

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Is the Utility of the GLIM Criteria Used to Diagnose Malnutrition Suitable for Bicultural Populations? Findings from Life and Living in Advanced Age Cohort Study in New Zealand (LiLACS NZ).

OBJECTIVES: To investigate associations between nutrition risk (determined by SCREEN-II) and malnutrition (diagnosed by the GLIM criteria) with five-year mortality in Māori and non-Māori of advanced age. DESIGN: A longitudinal cohort study. SETTING: Bay of Plenty and Lakes regions of New Zealand. PARTICIPANTS: 255 Māori; 400 non-Māori octogenarians. MEASUREMENTS: All participants were screened for nutrition risk using the Seniors in the Community: Risk Evaluation for Eating and Nutrition (SCREEN-II). Those at high nutrition risk (SCREEN-II score 0.05) but was for non-Māori. This association remained significant after adjustment for other predictors of death (OR (95% CI); 0.50 (0.29, 0.86), P< 0.05). Reduced food intake was the only GLIM criterion predictive of five-year mortality for Māori (HR (95% CI); 10.77 (4.76, 24.38), P <0.001). For non-Māori, both aetiologic and phenotypic GLIM criteria were associated with five-year mortality. CONCLUSION: Nutrition risk, but not malnutrition diagnosed by the GLIM criteria was significantly associated with mortality for Māori. Conversely, both nutrition risk and malnutrition were significantly associated with mortality for non-Māori. Appropriate phenotypic criteria for diverse populations are needed within the GLIM framework.Publishe

Gene Structure Evolution of the Na+-Ca2+ Exchanger (NCX) Family

<p>Abstract</p> <p>Background</p> <p>The Na⁺-Ca²⁺exchanger (NCX) is an important regulator of cytosolic Ca²⁺levels. Many of its structural features are highly conserved across a wide range of species. Invertebrates have a single <it>NCX </it>gene, whereas vertebrate species have multiple <it>NCX </it>genes as a result of at least two duplication events. To examine the molecular evolution of <it>NCX </it>genes and understand the role of duplicated genes in the evolution of the vertebrate <it>NCX </it>gene family, we carried out phylogenetic analyses of <it>NCX </it>genes and compared <it>NCX </it>gene structures from sequenced genomes and individual clones.</p> <p>Results</p> <p>A single <it>NCX </it>in invertebrates and the protochordate <it>Ciona</it>, and the presence of at least four <it>NCX </it>genes in the genomes of teleosts, an amphibian, and a reptile suggest that a four member gene family arose in a basal vertebrate. Extensive examination of mammalian and avian genomes and synteny analysis argue that <it>NCX4 </it>may be lost in these lineages. Duplicates for <it>NCX1</it>, <it>NCX2</it>, and <it>NCX4 </it>were found in all sequenced teleost genomes. The presence of seven genes encoding <it>NCX </it>homologs may provide teleosts with the functional specialization analogous to the alternate splicing strategy seen with the three <it>NCX </it>mammalian homologs.</p> <p>Conclusion</p> <p>We have demonstrated that <it>NCX4 </it>is present in teleost, amphibian and reptilian species but has been secondarily and independently lost in mammals and birds. Comparative studies on conserved vertebrate homologs have provided a possible evolutionary route taken by gene duplicates subfunctionalization by minimizing homolog number.</p

Successive use of shared space by badgers and cattle: implications for Mycobacterium bovis transmission

Managing infectious disease demands understanding pathogen transmission. In Britain, transmission of Mycobacterium bovis from badgers (Meles meles) to cattle hinders the control of bovine tuberculosis (TB), but the mechanism of such transmission is uncertain. As badgers and cattle seldom interact directly, transmission might occur in their shared environment through contact with contamination such as faeces, urine and saliva. We used concurrent GPS collar tracking of badgers and cattle at four sites in Cornwall, southwest Britain, to test whether each species used locations previously occupied by the other species, within the survival time of M. bovis bacteria. Although analyses of the same data set showed that badgers avoided cattle, we found no evidence that this avoidance persisted over time: neither GPS-collared badgers nor cattle avoided space which had been occupied by the other species in the preceding 36 h. Defining a contact event as an animal being located <5 m from space occupied by the other species within the previous 36 h, we estimated that a herd of 176 cattle (mean herd size in our study areas) would contact badgers at least 6.0 times during an average 24-h period. Similarly, we estimated that a social group of 3.5 badgers (mean group size in our study areas) would contact cattle at least 0.76 times during an average night. Such frequent successive use of the same shared space, within the survival time of M. bovis bacteria, could potentially facilitate M. bovis transmission via the environment

Use of farm buildings by wild badgers: implications for the transmission of bovine tuberculosis

Diseases transmitted from wildlife to livestock or people may be managed more effectively if it is known where transmission occurs. In Britain, farm buildings have been proposed as important sites of Mycobacterium bovis transmission between wild badgers (Meles meles) and cattle, contributing to the maintenance of bovine tuberculosis (TB). Farmers are therefore advised to exclude badgers from buildings. We used GPS-collars and remote cameras to characterise badgers’ use of farm buildings at four TB-affected sites in southwestern Britain. Across 54 GPS-collared badgers, 99.8% of locations fell ≥3m from farm buildings. Remote cameras deployed in feed stores recorded just 12 nights with badger visits among 3,134 store-nights of monitoring. GPS-collared badgers used space near farm buildings less than expected based on availability, significantly preferring land ≥100m from buildings. There was no positive association between badgers’ use of farm buildings and the infection status of either badgers or cattle. Six GPS-collared badgers which regularly visited farm buildings all tested negative for M. bovis. Overall, test-positive badgers spent less time close to farm buildings than did test-negative animals. Badger visits to farm buildings were more frequent where badger population densities were high. Our findings suggest that, while buildings may offer important opportunities for M. bovis transmission between badgers and cattle, building use by badgers is not a prerequisite for such transmission. Identifying ways to minimise infectious contact between badgers and cattle away from buildings is therefore a management priority