TASK DEFINITION: In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.
PROBLEM: Influenza infection and pneumonia are known to cause much of their mortality by inducing acute respiratory distress syndrome (ARDS), which is the most severe form of acute lung injury (ALI). Angiotensin-converting enzyme 2 (ACE2), which is a negative regulator of angiotensin II in the renin-angiotensin system, has been reported to have a crucial role in ALI. Downregulation of ACE2 is always associated with the ALI or ARDS induced by avian influenza virus, severe acute respiratory syndrome-coronavirus, respiratory syncytial virus and sepsis. However, the molecular mechanism of the decreased expression of ACE2 in ALI is unclear. Here we show that avian influenza virus H5N1 induced the upregulation of miR-200c-3p, which was then demonstrated to target the 3′-untranslated region of ACE2. Then, we found that nonstructural protein 1 and viral RNA of H5N1 contributed to the induction of miR-200c-3p during viral infection. Additionally, the synthetic analog of viral double-stranded RNA (poly (I:C)), bacterial lipopolysaccharide and lipoteichoic acid can all markedly increase the expression of miR-200c-3p in a nuclear factor-κB-dependent manner. Furthermore, markedly elevated plasma levels of miR-200c-3p were observed in severe pneumonia patients. The inhibition of miR-200c-3p ameliorated the ALI induced by H5N1 virus infection in vivo, indicating a potential therapeutic target. Therefore, we identify a shared mechanism of viral and bacterial lung infection-induced ALI/ARDS via nuclear factor-κB-dependent upregulation of miR-200c-3p to reduce ACE2 levels, which leads increased angiotensin II levels and subsequently causes lung injury.

SOLUTION: miRNA-200c-3p is crucial in acute respiratory distress syndrome

PROBLEM: One sentence summary: CmpA is an OmpA-like protein in Legionella pneumophila that is required for efficient intracellular replication in both primary macrophages and in the environmental host Acanthamoeba castellanii. Editor: Akio Nakane The OmpA-like protein domain has been associated with peptidoglycan-binding proteins, and is often found in virulence factors of bacterial pathogens. The intracellular pathogen Legionella pneumophila encodes for six proteins that contain the OmpA-like domain, among them the highly conserved uncharacterized protein we named CmpA. Here we set out to characterize the CmpA protein and determine its contribution to intracellular survival of L. pneumophila. Secondary structure analysis suggests that CmpA is an inner membrane protein with a peptidoglycan-binding domain at the C-teminus. A cmpA mutant was able to replicate normally in broth, but failed to compete with an isogenic wild-type strain in an intracellular growth competition assay. The cmpA mutant also displayed significant intracellular growth defects in both the protozoan host Acanthamoeba castellanii and in primary bone marrow-derived macrophages, where uptake into the cells was also impaired. The cmpA phenotypes were completely restored upon expression of CmpA in trans. The data presented here establish CmpA as a novel virulence factor of L. pneumophila that is required for efficient intracellular replication in both mammalian and protozoan hosts.

SOLUTION: A conserved OmpA-like protein in Legionella pneumophila required for efficient intracellular replication

PROBLEM: In vitro, nitric oxide (NO) has been shown to have antimicrobial activity against a wide range of viruses, including influenza A virus. Therefore, we hypothesized that inhaled nitric oxide (iNO) would increase survival in vivo by reducing the viral load in C57Bl/6 mice infected with a lethal dose of influenza A/WSN/33 (H1N1; WSN/33) virus. NO was delivered to influenza-infected mice either continuously or intermittently at 80 or 160 ppm, respectively, using both prophylactic and post-infection treatment strategies. Murine survival and weight loss were assessed, and lung viral load was quantified via plaque assay. Here, we report that iNO administered prophylactically or post-influenza infection failed to improve survival of infected mice. No difference in lung viral load was observed between experimental groups. Although NO has antiviral activity against influenza A virus in vitro, iNO therapy provided no apparent benefit when used for treatment of influenza A virus infection in vivo.

SOLUTION:
Inhaled Nitric Oxide Therapy Fails to Improve Outcome in Experimental Severe Influenza