The domestication of the probiotic bacterium Lactobacillus acidophilus

Lactobacillus acidophilus is a Gram-positive lactic acid bacterium that has had widespread historical use in the dairy industry and more recently as a probiotic. Although L. acidophilus has been designated as safe for human consumption, increasing commercial regulation and clinical demands for probiotic validation has resulted in a need to understand its genetic diversity. By drawing on large, well-characterised collections of lactic acid bacteria, we examined L. acidophilus isolates spanning 92 years and including multiple strains in current commercial use. Analysis of the whole genome sequence data set (34 isolate genomes) demonstrated L. acidophilus was a low diversity, monophyletic species with commercial isolates essentially identical at the sequence level. Our results indicate that commercial use has domesticated L. acidophilus with genetically stable, invariant strains being consumed globally by the human population

Changes in serogroup and genotype prevalence among carried meningococci in the United Kingdom during vaccine implementation.

BACKGROUND: Herd immunity is important in the effectiveness of conjugate polysaccharide vaccines against encapsulated bacteria. A large multicenter study investigated the effect of meningococcal serogroup C conjugate vaccine introduction on the meningococcal population. METHODS: Carried meningococci in individuals aged 15-19 years attending education establishments were investigated before and for 2 years after vaccine introduction. Isolates were characterized by multilocus sequence typing, serogroup, and capsular region genotype and changes in phenotypes and genotypes assessed. RESULTS: A total of 8462 meningococci were isolated from 47 765 participants (17.7%). Serogroup prevalence was similar over the 3 years, except for decreases of 80% for serogroup C and 40% for serogroup 29E. Clonal complexes were associated with particular serogroups and their relative proportions fluctuated, with 12 statistically significant changes (6 up, 6 down). The reduction of ST-11 complex serogroup C meningococci was probably due to vaccine introduction. Reasons for a decrease in serogroup 29E ST-254 meningococci (from 1.8% to 0.7%) and an increase in serogroup B ST-213 complex meningococci (from 6.7% to 10.6%) were less clear. CONCLUSIONS: Natural fluctuations in carried meningococcal genotypes and phenotypes a can be affected by the use of conjugate vaccines, and not all of these changes are anticipatable in advance of vaccine introduction

Rhinosporidium seeberi: a human pathogen from a novel group of aquatic protistan parasites.

Rhinosporidium seeberi, a microorganism that can infect the mucosal surfaces of humans and animals, has been classified as a fungus on the basis of morphologic and histochemical characteristics. Using consensus polymerase chain reaction (PCR), we amplified a portion of the R. seeberi 18S rRNA gene directly from infected tissue. Analysis of the aligned sequence and inference of phylogenetic relationships showed that R. seeberi is a protist from a novel clade of parasites that infect fish and amphibians. Fluorescence in situ hybridization and R. seeberi- specific PCR showed that this unique 18S rRNA sequence is also present in other tissues infected with R. seeberi. Our data support the R. seeberi phylogeny recently suggested by another group. R. seeberi is not a classic fungus, but rather the first known human pathogen from the DRIPs clade, a novel clade of aquatic protistan parasites (Ichthyosporea)

Long-term evolution of antigen repertoires among carried meningococci

Most studies of bacterial pathogen populations have been based on isolates collected from individuals with disease, or their contacts, over short time periods. For commensal organisms that occasionally cause disease, such as Neisseria meningitidis, however, the analysis of isolates from long-term asymptomatic carriage is necessary to elucidate their evolution and population structure. Here, we use mathematical models to analyse the structuring and dynamics of three vaccine-candidate antigens among carried meningococcal isolates collected over nearly 30 years in the Czech Republic. The data indicate that stable combinations of antigenic alleles were maintained over this time period despite evidence for high rates of recombination, consistent with theoretical models in which strong immune selection can maintain non-overlapping combinations of antigenic determinants in the presence of recombination. We contrast this antigenic structure with the overlapping but relatively stable combinations of the housekeeping genes observed among the same isolates, and use a novel network approach to visualize these relationships

Size and emotion or depth and emotion? Evidence, using Matryoshka (Russian) dolls, of children using physical depth as a proxy for emotional charge

Background: The size and emotion effect is the tendency for children to draw people and other objects with a positive emotional charge larger than those with a negative or neutral charge. Here we explored the novel idea that drawing size might be acting as a proxy for depth (proximity).Methods: Forty-two children (aged 3-11 years) chose, from 2 sets of Matryoshka (Russian) dolls, a doll to represent a person with positive, negative or neutral charge, which they placed in front of themselves on a sheet of A3 paper. Results: We found that the children used proximity and doll size, to indicate emotional charge. Conclusions: These findings are consistent with the notion that in drawings, children are using size as a proxy for physical closeness (proximity), as they attempt with varying success to put positive charged items closer to, or negative and neutral charge items further away from, themselves

Boomerang effects of gambling warnings exposed to non-problem gamblers

Gambling is the most popular form of entertainment in most markets where it is legal. Theindustry has embraced technology and is a growing category online and through mobileplatforms. Governments throughout the world worry about the product when gambling ismore widely available and more private to play. Warnings for problem gambling have longbeen used in land-based gambling venues but online gambling often does not have thisremedy. In addition, non-problem gamblers make up about 99% of gamblers but littleresearch has tested their reaction to warnings. An online casino was developed to testwarnings and found that a significant proportion of non-problem gamblers gambled morefrequently after exposure to the warnings. Because increased frequency of gambling is one symptom of problem gambling, the implications of these findings are discussed in terms of future remedies for consumers that have problems with gambling products

Post-impact heating of a crater lake

Lacustrine sediments from the 24 km diameter Boltysh impact structure record the rapid formation of an intra-crater lake. Stable isotope compositions and organic maturity parameters from the lake sediments deposited post-impact show that they were heated by underlying impactites. This heating is attributed to the establishment of an impact- generated hydrothermal system. Estimates of the duration of heating are ~30 – 40 k.y. consistent with the suggestion that crater lakes extend the longevity of impact-generated hydrothermal systems

Modelling Long Term Disability following Injury: Comparison of Three Approaches for Handling Multiple Injuries

BACKGROUND: Injury is a leading cause of the global burden of disease (GBD). Estimates of non-fatal injury burden have been limited by a paucity of empirical outcomes data. This study aimed to (i) establish the 12-month disability associated with each GBD 2010 injury health state, and (ii) compare approaches to modelling the impact of multiple injury health states on disability as measured by the Glasgow Outcome Scale - Extended (GOS-E). METHODS: 12-month functional outcomes for 11,337 survivors to hospital discharge were drawn from the Victorian State Trauma Registry and the Victorian Orthopaedic Trauma Outcomes Registry. ICD-10 diagnosis codes were mapped to the GBD 2010 injury health states. Cases with a GOS-E score >6 were defined as "recovered." A split dataset approach was used. Cases were randomly assigned to development or test datasets. Probability of recovery for each health state was calculated using the development dataset. Three logistic regression models were evaluated: a) additive, multivariable; b) "worst injury;" and c) multiplicative. Models were adjusted for age and comorbidity and investigated for discrimination and calibration. FINDINGS: A single injury health state was recorded for 46% of cases (1-16 health states per case). The additive (C-statistic 0.70, 95% CI: 0.69, 0.71) and "worst injury" (C-statistic 0.70; 95% CI: 0.68, 0.71) models demonstrated higher discrimination than the multiplicative (C-statistic 0.68; 95% CI: 0.67, 0.70) model. The additive and "worst injury" models demonstrated acceptable calibration. CONCLUSIONS: The majority of patients survived with persisting disability at 12-months, highlighting the importance of improving estimates of non-fatal injury burden. Additive and "worst" injury models performed similarly. GBD 2010 injury states were moderately predictive of recovery 1-year post-injury. Further evaluation using additional measures of health status and functioning and comparison with the GBD 2010 disability weights will be needed to optimise injury states for future GBD studies

Evidence for Bluegill Spawning Plasticity Obtained by Disentangling Complex Factors Related to Recruitment

Fishes can exhibit many forms of plasticity to maximize fitness. However, limited information exists on the ability of freshwater fish to adjust spawning behavior and characteristics (e.g., timing, duration, magnitude of spawning events) to minimize mortality of recruits and ultimately maximize fitness.Wewanted to test the life history hypothesis for bluegill (Lepomis macrochirus) (i.e., opportunistic strategy) utilizing existing literature and results from our study to further evaluate the potential for spawning plasticity in this species. Our objective was to identify bluegill recruitment bottlenecks (i.e., periods of high mortality) and factors associated with these events in a single lake during 7 consecutive years. Bluegills exhibited shorter spawning durations and fewer spawning pulses (i.e., peaks in larval production) compared with bluegill in previous studies. Late-hatched (compared with early-hatched) bluegills consistently contributed the most to the fall juvenile population; these recruitment patterns were primarily attributed to biotic drivers. Our study suggests that bluegill could exhibit spawning plasticity and extends our current understanding of adaptations that are potentially capable of increasing fitness for a freshwater fish species under a wide range of environmental conditions and uncertainty. Les poissons peuvent présenter différentes formes de plasticité leur permettant de maximiser leur aptitude. Peu de renseignements sont toutefois disponibles sur la capacité des poissons d\u27eau douce d\u27ajuster leur comportement de frai et les caractéristiques de ce dernier (p. ex. moment, durée, magnitude des évènements de frai) afin de minimiser la mortalité des recrues et, au final, maximiser leur aptitude. Nous voulions tester l\u27hypothèse du cycle biologique (c.-a` -d. stratégie opportuniste) pour le crapet arlequin (Lepomis macrochirus) a` la lumière d\u27études existantes et des résultats de notre étude pour évaluer plus en détail le potentiel de plasticité du frai chez cette espèce. L\u27objectif consistait a` cerner les goulots d\u27étranglement en ce qui concerne le recrutement de crapets arlequins (c.-a` -d. périodes de mortalité élevée) et les facteurs associés a` ces évènements dans un seul lac pendant 7 années consécutives. Comparativement aux études antérieures, les crapets arlequins présentaient des durées de frai plus courtes et moins de pointes de frai (ou de production de larves). La contribution a` la population juvénile automnale des crapets arlequins a` éclosion tardive était uniformément plus importante que celle des individus a` éclosion précoce, ces motifs de recrutement étant principalement attribuables a` des facteurs biotiques. L\u27étude donne a` penser que les crapets arlequins pourraient présenter une plasticité de frai et elle élargit la compréhension actuelle des adaptations pouvant potentiellement accroître l\u27aptitude d\u27une espèce de poissons dulcicoles pour un vaste éventail de conditions ambiantes et de niveaux d\u27incertitude