Population structure and associated phenotypes of Salmonella enterica serovars Derby and Mbandaka overlap with host range

BACKGROUND:The Salmonella enterica serovar Derby is frequently isolated from pigs and turkeys whereas serovar Mbandaka is frequently isolated from cattle, chickens and animal feed in the UK. Through comparative genomics, phenomics and mutant construction we previously suggested possible mechanistic reasons why these serovars demonstrate apparently distinct host ranges. Here, we investigate the genetic and phenotypic diversity of these two serovars in the UK. We produce a phylogenetic reconstruction and perform several biochemical assays on isolates of S. Derby and S. Mbandaka acquired from sites across the UK between the years 2000 and 2010. RESULTS:We show that UK isolates of S. Mbandaka comprise of one clonal lineage which is adapted to proficient utilisation of metabolites found in soya beans under ambient conditions. We also show that this clonal lineage forms a biofilm at 25 °C, suggesting that this serovar maybe well adapted to survival ex vivo, growing in animal feed. Conversely, we show that S. Derby is made of two distinct lineages, L1 and L2. These lineages differ genotypically and phenotypically, being divided by the presence and absence of SPI-23 and the ability to more proficiently invade porcine jejunum derived cell line IPEC-J2. CONCLUSION:The results of this study lend support to the hypothesis that the differences in host ranges of S. Derby and S. Mbandaka are adaptations to pathogenesis, environmental persistence, as well as utilisation of metabolites abundant in their respective host environments

Macrophage phenotype is associated with disease severity in preterm infants with chronic lung disease.

The etiology of persistent lung inflammation in preterm infants with chronic lung disease of prematurity (CLD) is poorly characterized, hampering efforts to stratify prognosis and treatment. Airway macrophages are important innate immune cells with roles in both the induction and resolution of tissue inflammation

THE NEED OF EARLY INTERVENTION IN CHILDHOOD ASTHMA

No abstract available

Evaluation of the allergenicity of infant formulas in a guinea pig model

In the present study we evaluated the allergenicity of infant formulas using a guinea pig model. Seven groups of ten guinea pigs each maintained on a diet free of cow milk received either water or pasteurized cow milk (PCM) or a conventional cow milk infant formula (CMF) or whey hydrolysate formula (WHF) to drink. On day 37 all the animals were challenged by intravenous injection with 0.5 mL of supernatant of either PCM or WHF. The reactions to the challenge were expressed as none, mild, severe nonfatal, and fatal. A score ranging from 0 to 3 was assigned to each animal and considered in the statistical analysis; P values are expressed as comparisons to the negative water-fed control group. Animals fed WHF and challenged with WHF (group 1), showed 10% fatal reactions and 50% severe but not fatal reactions (P less than .05). When challenged with PCM (group 2), 40% showed a mild reaction. Cow milk formula-fed animals showed 10% fatal reactions and 70% severe reactions when challenged with WHF (group 3). The same challenge caused 40% severe reactions in animals fed PCM (group 4) (P greater than .05). Animals fed and challenged with PCM (group 5) showed 100% fatal reaction (P less than .01). Animals fed water showed no reaction when challenged with either WHF (group 6) or PCM (group 7). The results suggest that WHF has less anaphylactic sensitizing power than PCM and CMF

Effects of industrial air pollution on pulmary response to methacoline in schoolchildren

The AA. reporte the effects of industrial air pollution on pulmary response to methacoline in schoolchildren

Theophylline inhibition of BCG-induced pulmonary inflammatory responses

The present study was performed to evaluate the effect(s) of theophylline on BCG-induced pulmonary inflammatory responses in an experimental rat model system. Five groups of six animals each received the following: group 1: theophylline-treated, BCG-challenged, and sacrificed three days later; group 2: saline-treated, BCG-challenged, and sacrificed three days later; group 3: theophylline-treated, BCG-challenged, and sacrificed five days later; group 4: saline-treated, BCG-challenged, and sacrificed five days later; and group 5: no treatment and no BCG-challenge ("absolute controls"). Quantitative recovery of bronchoalveolar lavage (BAL) cells was performed and compared with histopathologic changes in lung specimens from each animal in all five groups. No significant differences in quantitative BAL cellular recovery were observed in theophylline-treated animals from saline-treated controls. There was a significant reduction in BAL cell number in saline-treated animals sacrificed five days after BCG-challenge (group 4) from that seen in saline-treated animals sacrificed three days after BCG-challenge (group 2). The most striking finding, however, was a marked diminution in granuloma formation induced by theophylline five days after BCG challenge (group 3). These findings suggest an antiinflammatory effect of theophyllin