St Thomas' Hospital

About: St Thomas' Hospital is a healthcare organization based out in London, United Kingdom. It is known for research contribution in the topics: Population & Pregnancy. The organization has 12105 authors who have published 15596 publications receiving 624309 citations. The organization is also known as: St Thomas's Hospital & St. Thomas's.

The Pathogenesis of Edema in Diabetic Maculopathy

Abstract: Diabetic maculopathy is characterized by the accumulation of extracellular fluid in Henle's layer and the inner nuclear layer of the retina. The localization of the edema is likely to be due, in part, to the relative barrier properties of the inner and outer plexiform layers. The origin of the extracellular fluid is from the intravascular compartment. Although changes to retinal blood flow may partly explain the extravasation of fluid, the most important mechanism is breakdown of the blood retinal barriers. Both the inner blood retinal barrier formed by the retinal capillary endothelial cell tight junctions and the outer barrier formed by the retinal pigment epithelial cell tight junctions can be affected. The mechanism of breakdown of the blood retinal barriers is likely to be changes to the tight junction proteins including occludin and ZO-1. The biochemical messenger inducing these changes may be vascular endothelial growth factor. The origin of this or other cofactors may be the retinal glial cells. The underlying biochemical stimulus to the production of vascular endothelial growth factor is chronic hyperglycaemia, but it is uncertain by what pathway this is effected.

Nanopore metagenomics enables rapid clinical diagnosis of bacterial lower respiratory infection.

Abstract: The gold standard for clinical diagnosis of bacterial lower respiratory infections (LRIs) is culture, which has poor sensitivity and is too slow to guide early, targeted antimicrobial therapy. Metagenomic sequencing could identify LRI pathogens much faster than culture, but methods are needed to remove the large amount of human DNA present in these samples for this approach to be feasible. We developed a metagenomics method for bacterial LRI diagnosis that features efficient saponin-based host DNA depletion and nanopore sequencing. Our pilot method was tested on 40 samples, then optimized and tested on a further 41 samples. Our optimized method (6 h from sample to result) was 96.6% sensitive and 41.7% specific for pathogen detection compared with culture and we could accurately detect antibiotic resistance genes. After confirmatory quantitative PCR and pathobiont-specific gene analyses, specificity and sensitivity increased to 100%. Nanopore metagenomics can rapidly and accurately characterize bacterial LRIs and might contribute to a reduction in broad-spectrum antibiotic use.