University of London

About: University of London is a education organization based out in London, United Kingdom. It is known for research contribution in the topics: Population & Public health. The organization has 44838 authors who have published 88086 publications receiving 4002499 citations. The organization is also known as: London University & Lond..

Emergence and global spread of epidemic healthcare-associated Clostridium difficile.

Abstract: Epidemic C. difficile (027/BI/NAP1) has rapidly emerged in the past decade as the leading cause of antibiotic-associated diarrhea worldwide. However, the key events in evolutionary history leading to its emergence and the subsequent patterns of global spread remain unknown. Here, we define the global population structure of C. difficile 027/BI/NAP1 using whole-genome sequencing and phylogenetic analysis. We show that two distinct epidemic lineages, FQR1 and FQR2, not one as previously thought, emerged in North America within a relatively short period after acquiring the same fluoroquinolone resistance-conferring mutation and a highly related conjugative transposon. The two epidemic lineages showed distinct patterns of global spread, and the FQR2 lineage spread more widely, leading to healthcare-associated outbreaks in the UK, continental Europe and Australia. Our analysis identifies key genetic changes linked to the rapid transcontinental dissemination of epidemic C. difficile 027/BI/NAP1 and highlights the routes by which it spreads through the global healthcare system.

Flight-to-Quality or Flight-to-Liquidity? Evidence from the Euro-Area Bond Market

Abstract: Do bond investors demand credit quality or liquidity? The answer is both, but at different times and for different reasons. Using data on the Euro-area government bond market, which features a unique negative correlation between credit quality and liquidity across countries, we show that the bulk of sovereign yield spreads is explained by differences in credit quality, though liquidity plays a non-trivial role especially for low credit risk countries and during times of heightened market uncertainty. In contrast, the destination of large flows into the bond market is determined almost exclusively by liquidity. We conclude that credit quality matters for bond valuation but that, in times of market stress, investors chase liquidity, not credit quality.

Concomitant infections, parasites and immune responses.

Abstract: Concomitant infections are common in nature and often involve parasites. A number of examples of the interactions between protozoa and viruses, protozoa and bacteria, protozoa and other protozoa, protozoa and helminths, helminths and viruses, helminths and bacteria, and helminths and other helminths are described. In mixed infections the burden of one or both the infectious agents may be increased, one or both may be suppressed or one may be increased and the other suppressed. It is now possible to explain many of these interactions in terms of the effects parasites have on the immune system, particularly parasite-induced immunodepression, and the effects of cytokines controlling polarization to the Th1 or Th2 arms of the immune response. In addition, parasites may be affected, directly or indirectly, by cytokines and other immune effector molecules and parasites may themselves produce factors that affect the cells of the immune system. Parasites are, therefore, affected when they themselves, or other organisms, interact with the immune response and, in particular, the cytokine network. The importance of such interactions is discussed in relation to clinical disease and the development and use of vaccines.