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.

Combinations of porcine respiratory coronavirus (PRCV) and either of two swine influenza viruses (H1N1 or H3N2) were administered intranasally and by aerosol to six-to eight-week-old specific pathogen:free pigs. The clinical responses, gross respiratory lesions and growth performances of these pigs were studied and compared with those of single (PRCV, H1N1 or H3N2) and mock-infected animals. PRCV infection caused fever, growth retardation and lung lesions, but no respiratory symptoms. Infection with swine influenza viruses caused rather similar, mild symptoms of disease, with H1N1 infection being the least severe. Combined infections with influenza viruses and PRCV did not appear to enhance the pathogenicity of these viruses. Furthermore, viruses were isolated more frequently from tissues and nasal swabs taken from 'single' than 'dual' infected animals, suggesting a possible in vivo interference between replication of PRCV and swine influenza virus.
Pathogenicity of concurrent infection of pigs with porcine respiratory coronavirus and swine influenza virus

Data are limited regarding 2 new human polyomaviruses, KI polyomavirus (KIPyV) and WU polyomavirus (WUPyV), in immunocompromised patients. We used realtime PCR to test for these and 12 respiratory viruses in 2,732 nasal wash samples collected during the fi rst year after allogeneic hematopoietic cell transplantation from 222 patients. Specimens were collected weekly until day 100; then at least every 3 months. One year after hematopoietic cell transplantation, the cumulative incidence estimate was 26% for KIPyV and 8% for WUPyV. Age <20 years predicted detection of KIPyV (hazard ratio [HR] 4.6) and WUPyV (HR 4.4), and detection of a respiratory virus in the previous 2 weeks predicted KIPyV detection (HR 3.4). Sputum production and wheezing were associated with detection of KIPyV in the past week and WUPyV in the past month. There were no associations with polyomavirus detection and acute graft versus host disease, cytomegalovirus reactivation, neutropenia, lymphopenia, hospitalization, or death.
WU and KI Polyomaviruses in Respiratory Samples from Allogeneic Hematopoietic Cell Transplant Recipients

Investigation of the secondary metabolites of the ascidian Herdmania momus led to the isolation and characterization of four new nucleoside derivatives (1) (2) (3) (4) . Structural studies showed that these derivatives represent a series of rare methylsulfinyladenosine derivatives of interconvertible transesterification isomers and/or sulfinyl epimers. The antiviral activities of these rare nucleosides were evaluated against a series of human pathogenic viruses. Marine ascidians are a rich source of chemically diverse secondary metabolites, with remarkable biological activities. 1,2 such as amino acid derivatives and complex alkaloids. [3] [4] [5] [6] [7] [8] [9] In our previous study on bioactive compounds from the solitary tunicate Herdmania momus, a series of amino acid derivatives (herdmanines A-M) were isolated. 3,4 As a part of continuing study on the metabolites of the same tunicate, four new complex nucleosides (1-4) containing the rare methylsulfinyladenosine were isolated. Details of the isolation, structure elucidation, and of the results of the antiviral screening of these metabolites are described herein. The combined MeOH and CH 2 Cl 2 extracts were sequentially partitioned between CH 2 Cl 2 and H 2 O, and n-BuOH and H 2 O. The n-BuOH-soluble fraction was subjected to chromatographic separation and purification to yield a series of nucleoside derived metabolites (1-4). 10 Compounds 1 and 2 were found to be interconvertible, and on standing at room temperature after HPLC separation, each compound afforded the same equilibrium ratio of compound 1-2 (56:44). Compounds 3 and 4 were also interconvertible, and on standing at room temperature produced an identical equilibrium mixture (56:44) as that of 1 and 2. Spectral analysis of these interconvertible compounds was performed on equilibrium mixtures. The equilibrium mixture of compounds 1 and 2 was a white powder. The (+)-FABMS spectrum of this mixture showed isotopic peaks of [M+2H] + and [M+3H] + at m/z 554/552 and 555/553, respectively, with an isotopic peak ratio of 1:1. This pseudomolecular ionic configuration is shared with various other nucleosides N N N N NH 2

Epimeric methylsulfinyladenosine derivatives from the marine ascidian Herdmania momus