Replication of live attenuated influenza vaccine viruses in human nasal epithelial cells is associated with H1N1 vaccine effectiveness.

In the 2013-2014 and 2015-2016 influenza seasons, live attenuated influenza vaccine (LAIV) generated reduced vaccine effectiveness (VE) against circulating H1N1 strains. This reduced VE coincided with the introduction of pandemic 2009 H1N1 (A/H1N1pdm09) vaccine virus reassortants, in place of pre-2009 seasonal H1N1 strains. Here, we explored one specific hypothesis for reduced VE; decreased replicative fitness of A/H1N1pdm09 strains in humans. Two A/H1N1pdm09 strains with reduced VE, A/California/07/2009 (A/CA09) and A/Bolivia/559/2013 (A/BOL13), were compared to pre-2009 seasonal H1N1 strains, A/New Caledonia/20/1999 (A/NC99) and A/South Dakota/6/2007 (A/SD07). Initial results showed that A/H1N1pdm09 strains had reduced multi-cycle infectivity in Madin-Darby Canine Kidney (MDCK) cells, compared to their pre-2009 counterparts. The A/BOL13 viral titre was found to be 2.65 log10/mL lower when measured by multi-cycle 50% tissue culture infectious dose (TCID50) assay compared to single-cycle fluorescent focus assay (FFA). By contrast, clinically effective A/NC99 titres differed by only 0.54 log10/mL. In human alveolar (A549) cells, A/H1N1pdm09 strains replicated less than pre-2009 strains, with A/CA09 and A/BOL13 generating lower peak viral titres over 5 days. This phenotype was corroborated in physiologically relevant, primary human nasal epithelial cells (hNECs). Here, peak titres for pre-2009 strains A/NC99 and A/SD07 were 8.43 log10 TCID50/mL and 8.52 log10 TCID50/mL, respectively, versus 6.89 log10 TCID50/mL and 6.06 log10 TCID50/mL for A/H1N1pdm09 strains A/CA09 and A/BOL13. This confirmed a reduced ability of A/H1N1pdm09 strains to sustain replication in human respiratory cells. Using this information, H1N1 candidate A/Slovenia/2903/2015 (A/SLOV15) was characterised for replacement of A/BOL13 in the 2017/18 LAIV. A/SLOV15 produced comparable single and multi-cycle infectivity titres (Δ 0.16 log10/mL) and reached a peak titre 1.23 log10 TCID50/mL higher than that of A/BOL13 in hNEC cultures. Taken together, these data suggest a reduction in sustained multi-cycle replication in human cells as a plausible root cause for reduced A/H1N1pdm09 VE.

Cellulose degradation by micromonosporas recovered from freshwater lakes and classification of these actinomycetes by DNA gyrase B gene sequencing.

A number of Micromonospora strains isolated from the water column, sediment, and cellulose baits placed in freshwater lakes were shown to be able to degrade cellulose in lake water without any addition of nutrients. A selective isolation method was also developed to demonstrate that CFU arose from both spores and hyphae that inhabit the lake environment. Gyrase B gene sequencing performed on the isolates identified a number of new centers of variation within Micromonospora, but the most actively cellulolytic strains were recovered in a single cluster that equated with the type species of the genus, M. chalcea.

Detection of novel Fibrobacter populations in landfill sites and determination of their relative abundance via quantitative PCR.

Members of the bacterial genus Fibrobacter have long been considered important components of the anaerobic cellulolytic community in the herbivore gut, but their presence and activity in other environments is largely unknown. In this study, a specific polymerase chain reaction (PCR) primer set, targeting the 16S rRNA gene of Fibrobacter spp., was applied to community DNA from five landfill sites followed by temporal thermal gel electrophoresis (TTGE) analysis of cloned amplification products. Phylogenetic analysis of clone sequences indicated the presence of novel clusters closely related to the genus Fibrobacter. There are two named species, Fibrobacter succinogenes and F. intestinalis, and only two of the 58 sequenced clones were identified with them, and both were F. succinogenes. The clone sequences from landfill were recovered in five distinct clusters within the Fibrobacter lineage, and four of these were novel. Quantitative PCR (qPCR) assays of reverse-transcribed community RNA from landfill leachates and rumen fluid samples indicated that the abundance of Fibrobacter spp. relative to total bacteria varied from 0.2% to 40% in landfill, and 21% to 32% in the rumen, and these data demonstrate that fibrobacters can be a significant component of the microbial community in landfill ecosystems. This is the first evidence for Fibrobacter spp. outside the gut ecosystem, and as the only cultivated representatives of this group are actively cellulolytic, their diversity and abundance points to a possible role in cellulose hydrolysis in landfill, and perhaps other anaerobic environments also.

Molecular biological detection of anaerobic gut fungi (Neocallimastigales) from landfill sites.

Oligonucleotide primers were designed for the 18S rRNA genes of members of the Neocallimastigales and used in a nested PCR protocol to amplify 787-bp fragments of DNA from landfill site samples. The specificities of the primers were confirmed by phylogenetic analysis of the environmental clone sequences, and this method can therefore now be used to investigate the ecology of the obligately anaerobic fungi. To our knowledge, this is the first demonstration of the occurrence of members of the Neocallimastigales outside the mammalian gut, and their distribution across the landfill samples examined here suggests that they are actively involved in cellulose degradation.

Levels of processing, transfer-appropriate processing, and the concept of robust encoding.

The theoretical status of levels of processing and its relation to the general principle of transfer-appropriate processing is discussed. One possible description of this relationship is that levels of processing has its effect by influencing the likelihood that the processing will prove to be transfer-appropriate. This transfer account of the levels effect is discussed in terms of the concept of robust encoding (Lockhart & Craik, 1990). Available evidence provides little support for any simple form of this concept, but a modified version is suggested as a possibility.

Conceptual transfer insimple insight problems.

Three experiments explored the conditions under which information presented in the first part of an experiment facilitates the subsequent solving of simple insight problems. We argue that previous unsuccessful attempts to obtain such facilitation are attributable to the experimenters' failure to present this information in a form that induces the conceptual operations needed to solve the problem. Substantial facilitation is obtained if the information is presented in a form that induces a few seconds of puzzlement and then a clue is presented that leads to an appropriate reconception; if identical information is presented without such a period of puzzlement and reconception, no facilitation is observed. The results demonstrate that conceptual processing operations, not merely informational content, must be relevant if conceptual transfer is to occur. One possible mechanism involved in such transfer is the indexing of concepts such that they contain pointers to conceptually anomalous episodes.