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.

Q: IFITM3 restricts cellular infection by multiple important viral pathogens, and is particularly critical for the innate immune response against influenza virus. Expression of IFITM3 expands acidic endolysosomal compartments and prevents fusion of endocytosed viruses, leading to their degradation. This small, 133 amino acid, antiviral protein is controlled by at least four distinct post-translational modifications. Positive regulation of IFITM3 antiviral activity is provided by Spalmitoylation, while negative regulatory mechanisms include lysine ubiquitination, lysine methylation and tyrosine phosphorylation. Herein, we describe specific insights into IFITM3 trafficking and activity that were provided by studies of IFITM3 post-translational modifications, and discuss evidence suggesting that IFITM3 adopts multiple membrane topologies involving at least one intramembrane domain in its antivirally active conformation.

A: Regulation of the trafficking and antiviral activity of IFITM3 by post-translational modifications
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Q: Advances in free radical research show that reactive oxygen and nitrogen oxide species, for example superoxide, nitric oxide (NO) and peroxynitrite, play an important role in the pathogenesis of different viral infections, including dengue virus. The pathogenic mechanism of dengue haemorrhagic fever (DHF) is complicated and is not clearly understood. The hallmarks of the dengue disease, the antibody-dependent enhancement, the shift from T-helper type 1 (Th1) to Th2 cytokine response and the cytokine tsunami resulting in vascular leakage can now be explained much better with the knowledge gained about NO and peroxynitrite. This paper makes an effort to present a synthesis of the current opinions to explain the pathogenesis of DHF/shock syndrome with NO on centre stage.

A: Nitric oxide in dengue and dengue haemorrhagic fever: necessity or nuisance?
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Q: Colibacillosis results from infection with avian pathogenic Escherichia coli bacteria. Healthy broilers are resistant to inhaled E. coli, but previous infection with vaccine or virulent strains of Infectious Bronchitis Virus (IBV) predisposes birds for severe colibacillosis. We investigated whether IBV affects recruitment and function of phagocytic cells and examined NO production, phagocytic and bactericidal activity, and kinetics of peripheral blood mononuclear cells (PBMC) and splenocytes. Moreover, we measured cytokine mRNA expression in lung and spleen samples. Broilers were inoculated with IBV H120 vaccine or virulent M41 and challenged 5 days later with E. coli 506. A PBS control and E. coli group without previous virus inoculation were also included. Birds were sacrificed at various time points after inoculation (h/dpi). Inoculation with IBV induced extended and more severe colibacillosis than with E. coli alone. At 4 dpi, the number of KUL-01 + PBMC in all E. coli-inoculated groups was significantly higher than in PBS-inoculated birds, which correlated with lesion scores. From 1 to 4 dpi, NO production by PBMC from all E. coliinoculated animals was elevated compared to PBS birds. Bactericidal activity of PBMC in IBV-inoculated animals at 7 dpi was lower than in PBS-and E. coli-inoculated birds, but phagocytic capacity and recruitment were not severely impaired. In spleen samples of IBV-infected animals reduced expression of IL-1b, IL-6, IL-8, IL-10, IL-18 and IFN-g mRNA was found 1 dpi. Our results suggest that enhanced colibacillosis after IBV infection or vaccination is caused at least by altered innate immunity and less by impairment of phagocytic cell function. #

A:
The role of phagocytic cells in enhanced susceptibility of broilers to colibacillosis after Infectious Bronchitis Virus infection
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