Pulmonary embolism: clinical presentation and diagnosis in the oldest old.

The incidence of pulmonary embolism (PE) in the oldest old (persons aged ≥85) is increasing, but there are limited data on its clinical features and diagnosis. We performed a retrospective cohort study of 302 consecutive patients with confirmed PE and compared the oldest old to the young (aged <65) and the younger old (aged 65-84). The most common symptoms in the oldest old were dyspnoea (74.3%) and tachypnoea (71.4%), but the prevalence of chest pain decreased with advancing age. Delayed diagnosis was most common in the oldest old and was associated with increasing age, absence of dyspnoea, presence of cardiorespiratory disease and a higher Charlson Comorbidity index. Better age-specific diagnostic pathways are required in this population.

Identification of Plasmid-Encoded sRNAs in a blaNDM-1-Harboring Multidrug-Resistance Plasmid pNDM-HK in Enterobacteriaceae.

Small RNAs (sRNAs) play significant roles in regulating gene expression post-transcriptionally in response to environmental changes in bacteria. In this work, we identified and characterized six novel sRNAs from an emerging multidrug-resistance (MDR) plasmid pNDM-HK, a New Delhi metallo-ß-lactamase 1 gene (blaNDM-1)-carrying IncL/M plasmid that has caused worldwide threat in recent years. These sRNAs are located at different regions of pNDM-HK, such as replication, stability, and variable regions. Moreover, one of the plasmid-encoded sRNAs (NDM-sR3) functions in an Hfq-dependent manner and possibly plays roles in the fitness of pNDM-HK carrying bacteria. In addition, we attempted to construct the phylogenetic tree based on these novel sRNAs and surprisingly, the sRNA-phylogenetic tree provided significant information about the evolutionary pathway of pNDM-HK, including possible gene acquisition and insertion from relevant plasmids. Moreover, the sRNA-phylogenetic tree can specifically cluster the IncM2 type and distinguish it from other IncL/M subtypes. In summary, this is the first study to systematically identify and characterize sRNAs from clinically-isolated MDR plasmids. We believe that these newly found sRNAs could lead to further understanding and new directions to study the evolution and dissemination of the clinically MDR bacterial plasmids.