Clinical Outcomes for Patients with Community-Acquired Pneumonia are Worse in Those with a History of Stroke

Background: Stroke is one of the most prevalent neurological diseases in the United States. Community-acquired pneumonia (CAP) is the leading cause of infections in survivors of stroke. There is limited research evaluating the clinical outcomes of CAP in patients with stroke. The objective of this study was to evaluate the clinical characteristics and outcomes of hospitalized patients with CAP and a history of stroke. Methods: This was a secondary analysis of the University of Louisville Pneumonia Study database. Patients were divided into two groups based on the presence or absence of a history of stroke. Clinical outcomes were length of stay, time to clinical stability, and one-year mortality, which were assessed via stratified Cox proportional hazards regression. Differences in risk of clinical outcomes were reported as adjusted hazard ratios. Results: We found no significant differences in time to clinical stability between the two groups. The median length of stay for patients with a history of stroke hospitalized with CAP was six days and for patients without stroke was five days (P=0.01). We observed a 16% higher risk of mortality in stroke patients with CAP than in the non-stroke population (P=0.001). Conclusions: This study indicates that hospitalized patients with CAP have a longer hospital stay and higher mortality than those without stroke

Cooperative and Antagonistic Contributions of Two Heterochromatin Proteins to Transcriptional Regulation of the Drosophila Sex Determination Decision

Eukaryotic nuclei contain regions of differentially staining chromatin (heterochromatin), which remain condensed throughout the cell cycle and are largely transcriptionally silent. RNAi knockdown of the highly conserved heterochromatin protein HP1 in Drosophila was previously shown to preferentially reduce male viability. Here we report a similar phenotype for the telomeric partner of HP1, HOAP, and roles for both proteins in regulating the Drosophila sex determination pathway. Specifically, these proteins regulate the critical decision in this pathway, firing of the establishment promoter of the masterswitch gene, Sex-lethal (Sxl). Female-specific activation of this promoter, SxlPe, is essential to females, as it provides SXL protein to initiate the productive female-specific splicing of later Sxl transcripts, which are transcribed from the maintenance promoter (SxlPm) in both sexes. HOAP mutants show inappropriate SxlPe firing in males and the concomitant inappropriate splicing of SxlPm-derived transcripts, while females show premature firing of SxlPe. HP1 mutants, by contrast, display SxlPm splicing defects in both sexes. Chromatin immunoprecipitation assays show both proteins are associated with SxlPe sequences. In embryos from HP1 mutant mothers and Sxl mutant fathers, female viability and RNA polymerase II recruitment to SxlPe are severely compromised. Our genetic and biochemical assays indicate a repressing activity for HOAP and both activating and repressing roles for HP1 at SxlPe

Drosophila Genes That Affect Meiosis Duration Are among the Meiosis Related Genes That Are More Often Found Duplicated

Using a phylogenetic approach, the examination of 33 meiosis/meiosis-related genes in 12 Drosophila species, revealed nine independent gene duplications, involving the genes cav, mre11, meiS332, polo and mtrm. Evidence is provided that at least eight out of the nine gene duplicates are functional. Therefore, the rate at which Drosophila meiosis/meiosis-related genes are duplicated and retained is estimated to be 0.0012 per gene per million years, a value that is similar to the average for all Drosophila genes. It should be noted that by using a phylogenetic approach the confounding effect of concerted evolution, that is known to lead to overestimation of the duplication and retention rate, is avoided. This is an important issue, since even in our moderate size sample, evidence for long-term concerted evolution (lasting for more than 30 million years) was found for the meiS332 gene pair in species of the Drosophila subgenus. Most striking, in contrast to theoretical expectations, is the finding that genes that encode proteins that must follow a close stoichiometric balance, such as polo, mtrm and meiS332 have been found duplicated. The duplicated genes may be examples of gene neofunctionalization. It is speculated that meiosis duration may be a trait that is under selection in Drosophila and that it has different optimal values in different species