Rice Bran Amendment Suppresses Potato Common Scab by Increasing Antagonistic Bacterial Community Levels in the Rhizosphere.

Potato common scab (PCS), caused by pathogenic Streptomyces spp., is a serious disease in potato production worldwide. Cultural practices, such as optimizing the soil pH and irrigation, are recommended but it is often difficult to establish stable disease reductions using these methods. Traditionally, local farmers in southwest Japan have amended soils with rice bran (RB) to suppress PCS. However, the scientific mechanism underlying disease suppression by RB has not been elucidated. The present study showed that RB amendment reduced PCS by repressing the pathogenic Streptomyces population in young tubers. Amplicon sequencing analyses of 16S ribosomal RNA genes from the rhizosphere microbiome revealed that RB amendment dramatically changed bacterial composition and led to an increase in the relative abundance of gram-positive bacteria such as Streptomyces spp., and this was negatively correlated with PCS disease severity. Most actinomycete isolates derived from the RB-amended soil showed antagonistic activity against pathogenic Streptomyces scabiei and S. turgidiscabies on R2A medium. Some of the Streptomyces isolates suppressed PCS when they were inoculated onto potato plants in a field experiment. These results suggest that RB amendment increases the levels of antagonistic bacteria against PCS pathogens in the potato rhizosphere.

Effect of free radical scavenger, edaravone, for patients with carbon monoxide poisoning.

OBJECTIVE: Chronic neurological symptoms after carbon monoxide (CO) poisoning are caused by various biological processes in the damaged brain, with free radicals playing roles as mediators in establishing pathological processes leading to chronic neurological symptoms under CO poisoning. This study aimed to clarify the effects of a free radical scavenger, edaravone, in patients with CO poisoning. METHODS: We retrospectively compared two groups comprising patients treated with hyperbaric oxygenation alone (Group A, n=25) or edaravone in addition to hyperbaric oxygenation (Group B, n=25). Edaravone was administrated intravenously at 30 mg every 12h for 7 days. Patient characteristics, general conditions on admission, and frequency of chronic neurological symptoms were compared between groups. Among patients showing chronic neurological symptoms, cognitive function and daily activity were also compared between groups. RESULTS: No significant differences in characteristics or general conditions on admission were identified between groups. In Group B, no patients presented with marked complications caused by edaravone. Although chronic persisting symptoms were less frequent in Group B (n=1, 0.04%) than in Group A (n=5, 20%), this difference was not significant. In the 11 patients showing chronic symptoms, scores for cognitive function and daily activity in the chronic phase were better in Group B than in Group A, but no significant differences were apparent. CONCLUSIONS: The present results suggest that edaravone represents a tolerable and feasible treatment for CO-poisoned patients. Further studies are needed to clarify whether edaravone can favorably influence chronic neurological symptoms caused by CO poisoning.