Comparisons of pathogenic course of two Heliothis virescens ascovirus isolates (HvAV-3i and HvAV-3j) in four noctuid (Lepidoptera) pest species.

Ascoviruses are fatal double-stranded DNA viruses with a special pathogenesis in which cells are converted into vesicles with virions. Several closely related ascovirus isolates that shared more than 90% genomic DNA identity showed different pathogenic courses in previous studies. To investigate the pathogenic differences between the related ascovirus isolates, Heliothis virescens ascovirus 3i (HvAV-3i) and Heliothis virescens ascovirus 3j (HvAV-3j) were used to inoculate four noctuid pest species (Helicoverpa armigera, Mythimna separata, Spodoptera frugiperda, and Spodoptera litura), and the pathogenic indexes were recorded. The mortality of HvAV-3i infected H. armigera and S. frugiperda was approximately 60%, while the other HvAV-infected larvae had mortality rates above 90%. The maximum lethal dilution ratios of HvAV-3i in H. armigera, M. separata, S. frugiperda, and S. litura were 1.90 × 107, 1.90 × 103, 1.90 × 108, and 1.90 × 104 viral genome DNA copies/mL, respectively, while the ratios of HvAV-3j were 8.22 × 106, 8.22 × 102, 8.22 × 105, and 8.22 × 103 viral genome DNA copies/mL, respectively. Extended larval survival time was found in the HvAV-infected larvae; median survival time of the HvAV-infected larvae ranged from 13 to 19 days. An additional larval instar was found in HvAV-infected M. separata, S. frugiperda, and S. litura. Larval growth and food intake were significantly inhibited from 2 days post-infection (dpi) in the tested H. armigera, S. frugiperda, and S. litura after infection with HvAV-3i or HvAV-3j. The detoxification enzyme activity of host larvae was influenced after infection with HvAVs, and two different regulation patterns were detected, one in infected H. armigera and M. separata and the other in S. frugiperda and S. litura. The results obtained in this study provide insights into the pathogenic characteristics of ascoviruses.

Effectiveness and safety of warfarin and anti-platelet drugs for the primary prevention of stroke in patients with non-valvular atrial fibrillation: a meta-analysis.

OBJECTIVE: To evaluate the effectiveness and safety of warfarin and anti-platelet drugs as the primary approach to the prevention of stroke in patients with non-valvular atrial fibrillation (NVAF). METHODS: Three English databases (the Cochrane library, Embase, and Medline), and three Chinese databases (the Chinese Biomedical Literature Database, Chinese National Knowledge Infrastructure, and Chinese Periodical Full-text Database of Science and Technology) were searched to select potentially eligible studies published before May, 2014. The studies were randomized controlled trials (RCTs) that investigated the effectiveness and safety of using warfarin and anti-platelet drugs in preventing stroke in NVAF patients; The statistical analysis was performed using the Review Manager 5.2 software provided by the Cochrane Collaboration. RESULTS: nine articles were finally included. Compared with antiplatelet drugs, warfarin treatment significantly reduced the risk of stroke (OR = 0.62, 95% CI 0.50-05.77), systemic embolism events (OR = 0.49, 95% CI 0.31-0.77), ischemic stroke events (OR = 0.46, 95% CI 0.36-0.59), stroke-related disability or death events (OR = 0.66, 95% CI 0.52-0.84). Warfarin did not increase the incidence of All-cause death events (OR = 0.92, 95% CI 0.78-1.08), intracranial hemorrhage events (OR = 1.28, 95% CI 0.85-1.93), major hemorrhage events (OR = 1.01, 95% CI 0.79-1.29). CONCLUSIONS: This meta-analysis found that compared with antiplatelet drugs, warfarin treatment significantly reduced the risk of stroke, systemic embolism events, ischemic stroke events, stroke-related disability or death events. And warfarin did not increase the incidence of All-cause death events, intracranial hemorrhage events, major hemorrhage events.