Rotaviruses are the single leading cause of life-threatening diarrhea affecting children under 5 years of age. Rotavirus entry into the host cell seems to occur by sequential interactions between virion proteins and v...Rotaviruses are the single leading cause of life-threatening diarrhea affecting children under 5 years of age. Rotavirus entry into the host cell seems to occur by sequential interactions between virion proteins and various cell surface molecules. The entry mechanisms seem to involve the contribution of cellular molecules having binding, chaperoning and oxido-reducing activities. It appears to be that the receptor usage and tropism of rotaviruses is determined by the species, cell line and rotavirus strain. Rotaviruses have evolved functions which can antagonize the host innate immune response, whereas are able to induce endoplasmic reticulum(ER) stress, oxidative stress and inflammatory signaling. A networking between ER stress, inflammation and oxidative stress is suggested, in which release of calcium from the ER increases the generation of mitochondrial reactive oxygen species(ROS) leading to toxic accumulation of ROS within ER and mitochondria. Sustained ER stress potentially stimulates inflammatory response through unfolded protein response pathways. However, the detailed characterization of the molecular mechanisms underpinning these rotavirus-induced stressful conditions is still lacking. The signaling events triggered by host recognition of virusassociated molecular patterns offers an opportunity for the development of novel therapeutic strategies aimed at interfering with rotavirus infection. The use of N-acetylcysteine, non-steroidal anti-inflammatory drugs and PPARγ agonists to inhibit rotavirus infection opens a new way for treating the rotavirus-induced diarrhea and complementing vaccines.展开更多
The effects of free chlorine disinfection of tap water and wastewater effluents on the infectivity, gene integrity and surface antigens of rotaviruses were evaluated by a bench-scale chlorine disinfection experiments....The effects of free chlorine disinfection of tap water and wastewater effluents on the infectivity, gene integrity and surface antigens of rotaviruses were evaluated by a bench-scale chlorine disinfection experiments. Plaque assays, integrated cell culture-quantitative RT- PCR （ICC-RT-qPCR）, RT-qPCR, and enzyme-linked immunosorbent assays （ELISA）, respectively, were used to assess the influence of the disinfectant on virus infectivity as well as genetic and antigenic integrity of simian rotavirus SA11 as a surrogate for human rotaviruses. The ICC-RT-qPCR was able to detect rotaviruses survival from chlorine disinfection at chlorine dose up to 20 mg/L （60 min contact）, which suggested a required chlorine dose of 5 folds （from 1 to 5 mg/L） higher than that indicated by the plaque assay to achieve 1.8 log10 reductions in tap water with 60 rain exposing. The VP7 gene was more resistant than the infectivity and existed at chlorine dose up to 20 mg/L （60 min contact）, while the antigencity was undetectable with chlorine dose more than 5 mg/L （60 min contact）. The water quality also impacted the inactivation efficiencies, and rotaviruses have a relatively higher resistant in secondary effluents than in the tap water under the same chlorine disinfection treatments. This study indicated that rotaviruses have a higher infectivity, gene and antigencity resistance to chlorine than that previously indicated by plaque assay only, which seemed to underestimate the resistance of rotaviruses to chlorine and the risk of rotaviruses in environments. Present results also suggested that re-evaluation of resistance of other waterborne viruses after disinfections by more sensitive infectivity detection method （such as ICC-RT-qPCR） may be necessary, to determine the adequate disinfectant doses required for the inactivation of waterborne viruses.展开更多
文摘Rotaviruses are the single leading cause of life-threatening diarrhea affecting children under 5 years of age. Rotavirus entry into the host cell seems to occur by sequential interactions between virion proteins and various cell surface molecules. The entry mechanisms seem to involve the contribution of cellular molecules having binding, chaperoning and oxido-reducing activities. It appears to be that the receptor usage and tropism of rotaviruses is determined by the species, cell line and rotavirus strain. Rotaviruses have evolved functions which can antagonize the host innate immune response, whereas are able to induce endoplasmic reticulum(ER) stress, oxidative stress and inflammatory signaling. A networking between ER stress, inflammation and oxidative stress is suggested, in which release of calcium from the ER increases the generation of mitochondrial reactive oxygen species(ROS) leading to toxic accumulation of ROS within ER and mitochondria. Sustained ER stress potentially stimulates inflammatory response through unfolded protein response pathways. However, the detailed characterization of the molecular mechanisms underpinning these rotavirus-induced stressful conditions is still lacking. The signaling events triggered by host recognition of virusassociated molecular patterns offers an opportunity for the development of novel therapeutic strategies aimed at interfering with rotavirus infection. The use of N-acetylcysteine, non-steroidal anti-inflammatory drugs and PPARγ agonists to inhibit rotavirus infection opens a new way for treating the rotavirus-induced diarrhea and complementing vaccines.
基金supported by the Special Fund of State Key Joint Laboratory of Environment Simulation and Pollution Control of China (No. 10Y04ESPCT)the National Natural Science Fundation of China (No. 51178242)the Major Science and Technology Program for Water Pollution Control and Treatment of China (No. 2008ZX07313-007)
文摘The effects of free chlorine disinfection of tap water and wastewater effluents on the infectivity, gene integrity and surface antigens of rotaviruses were evaluated by a bench-scale chlorine disinfection experiments. Plaque assays, integrated cell culture-quantitative RT- PCR （ICC-RT-qPCR）, RT-qPCR, and enzyme-linked immunosorbent assays （ELISA）, respectively, were used to assess the influence of the disinfectant on virus infectivity as well as genetic and antigenic integrity of simian rotavirus SA11 as a surrogate for human rotaviruses. The ICC-RT-qPCR was able to detect rotaviruses survival from chlorine disinfection at chlorine dose up to 20 mg/L （60 min contact）, which suggested a required chlorine dose of 5 folds （from 1 to 5 mg/L） higher than that indicated by the plaque assay to achieve 1.8 log10 reductions in tap water with 60 rain exposing. The VP7 gene was more resistant than the infectivity and existed at chlorine dose up to 20 mg/L （60 min contact）, while the antigencity was undetectable with chlorine dose more than 5 mg/L （60 min contact）. The water quality also impacted the inactivation efficiencies, and rotaviruses have a relatively higher resistant in secondary effluents than in the tap water under the same chlorine disinfection treatments. This study indicated that rotaviruses have a higher infectivity, gene and antigencity resistance to chlorine than that previously indicated by plaque assay only, which seemed to underestimate the resistance of rotaviruses to chlorine and the risk of rotaviruses in environments. Present results also suggested that re-evaluation of resistance of other waterborne viruses after disinfections by more sensitive infectivity detection method （such as ICC-RT-qPCR） may be necessary, to determine the adequate disinfectant doses required for the inactivation of waterborne viruses.
