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: Human parainfluenza viruses (HPIVs) are common causes of severe pediatric respiratory viral disease. We characterized wild-type HPIV2 infection in an in vitro model of human airway epithelium (HAE) and found that the virus replicates to high titer, sheds apically, targets ciliated cells, and induces minimal cytopathology. Replication of an experimental, live attenuated HPIV2 vaccine strain, containing both temperature sensitive (ts) and non-ts attenuating mutations, was restricted >30-fold compared to rHPIV2-WT in HAE at 32°C and exhibited little productive replication at 37°C. This restriction paralleled attenuation in the upper and lower respiratory tract of African green monkeys, supporting the HAE model as an appropriate and convenient system for characterizing HPIV2 vaccine candidates.

SOLUTION: Growth restriction of an experimental live attenuated human parainfluenza virus type 2 vaccine in human ciliated airway epithelium in vitro parallels attenuation in African green monkeys

PROBLEM: Glycyrrhetinic acid monoglucuronide (GAMG) is a great value-added and has considerable commercial interest due to its strong pharmacological activities and functional low-calorie sweetener. However GAMG is quite rare in natural plants, and it must be prepared from glycyrrhizin (GL) by hydrolysing one terminal glucuronic acid. β-Glucuronidase is the key enzyme in the biotransformation of GL to GAMG, but its activities need to be enhanced to facilitate the industrial large-scale production of GAMG. In this study, we identified that isoliquiritigenin (ISL), as one of chemical compositions from the total flavonoids glycyrrhiza (TFG), can significantly enhance β-glucuronidase activity in vitro. Measurements using high-performance liquid chromatography (HPLC) showed that the activity of β-glucuronidase could be increased by 2.66-fold via the addition of ISL to a β-glucuronidase solution that contained GL at a 3:10 molar ratio of ISL to GL. ISL was concluded to be an activator because ISL could reduce the K m and E a of β-glucuronidase reacting with GL. This study sheds new light on the mechanism of βglucuronidase and helps to make industrial production of GAMG through fermentation feasible. Published: xx xx xxxx OPEN www.nature.com/scientificreports/ 2 Scientific RepoRts | 7: 12503 |

SOLUTION: Identification of isoliquiritigenin as an activator that stimulates the enzymatic production of glycyrrhetinic acid monoglucuronide OPEN

PROBLEM: This paper describes the isolation of porcine epidemic diarrhea (PED) virus in Vero and porcine cell cultures, and the in¯uence of age on disease in experimental infection. PED virus was isolated from the small intestine of piglets inoculated with PED samples and cultured in Vero, porcine bladder and kidney cells propagated in collagen-coated tissue culture plates in maintenance medium (MM) containing trypsin. In porcine bladder and kidney cell cultures inoculated with isolated PED virus, cytopathic effects (CPE) including cell fusion were detected. Speci®c brilliant¯uorescence was observed in the cytoplasm of these cells. Two-and 7-day old, and 2-, 4-, 8-and 12-week old speci®c pathogen-free (SPF) pigs were orally inoculated with PED virus isolated from an outbreak. All 2-and 7-day old pigs inoculated developed severe watery diarrhea from post-inoculation day (PID) 1 and died between PID 3 and 4. Although three of ®ve 2-week old pigs developed diarrhea on PID 1±4, they eventually recovered. In the 4-week old group, three of ®ve pigs had mild diarrhea for 1±2 days. None of the 8-and 12-week old pigs showed any clinical signs. Antibodies against PED virus were detected in all surviving pigs by virus neutralization (VN) test and immuno¯uorescence assay (IFA). Therefore, there is an age-dependent resistance to pathogenic PED virus infection in pigs. #

SOLUTION:
Isolation of porcine epidemic diarrhea virus in porcine cell cultures and experimental infection of pigs of different ages