Elsinochrome pigments produced by many phytopathogenic Elsinoë spp. are nonhost-selective toxins which react with oxygen molecules after light activation to produce highly toxic reactive oxygen species. The structures and chemical properties of four derivatives are well known. However, the biological roles of elsinochromes in fungal pathogenesis are poorly understood. Many isolates of Elsinoë fawcettii causing citrus scab are able to produce elsinochromes under axenic conditions. In this article, we report the cloning, expression, and functional characterization of the polyketide synthase-encoding gene, EfPKS1, which we show is required for the production of elsinochromes and fungal pathogenesis. Targeted disruption of EfPKS1 in E.fawcettii completely abrogated elsinochrome production, drastically reduced conidiation, and significantly decreased lesion formation on rough lemon leaves. All mutant phenotypes were restored to the wild type in fungal strains expressing a functional copy of EfPKS1. Accumulation of the EfPKS1 transcript and elsinochromes by a wild-type strain appears to be coordinately regulated by light, nutrients, and pH. The results indicate that the product of EfPKS1 is involved in the biosynthesis of elsinochromes via a fungal polyketide pathway, and that elsinochromes play an important role in fungal pathogenesis.

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Elsinochromes are nonhost-selective, light-activated, polyketide-derived toxins produced by many phytopathogenic Elsinoë species. We recently showed that the polyketide synthase-encoding gene EfPKS1 is essential for elsinochrome biosynthesis in the citrus scab fungus Elsinoë fawcettii. Sequence analysis beyond the EfPKS1 gene identified nine putative ORFs: four genes, designated RDT1, TSF1, PRF1 and ECT1, all encode polypeptides likely to have biosynthetic or efflux functions; five additional genes, OXR1 and EfHP1 to EfHP4, encode hypothetical proteins of unknown function. Northern-blot analysis revealed that expression of these genes in E. fawcettii was not completely correlated with accumulation of elsinochromes under nitrogen limitation, alkaline pH or high concentrations of glucose. Targeted disruption of the TSF1 gene, encoding a putative transcriptional activator, yielded fungal mutants unable to produce elsinochromes, and defective in both conidiation and expression of RDT1, EfPKS1, PRF1 and EfHP1, whereas expression of RDT1, TSF1, PRF1 and ECT1 was nearly abolished in EfPKS1-disrupted mutants. By contrast, expression of OXR1, EfHP2 and EfHP3 was not affected by disrupting either EfPKS1 or TSF1. Taken together, the results indicate that in addition to polyketide synthase, the products of TSF1 and other adjacent genes may also play a crucial role in elsinochrome production.

Summary• Elsinochromes are the red/orange pigments produced by many Elsinoë fungal species and are structurally similar to the phytotoxin, cercosporin. Here, pigments were extracted from cultures of a citrus pathogen, Elsinoë fawcettii and tested for cellular toxicity.• On irradiation with light, elsinochromes rapidly killed suspension cultured citrus and tobacco cells. The toxicity was decreased by adding the singlet oxygen ( 1 O 2 ) quenchers (bixin (carotenoid carboxylic acid), DABCO (1, 4-diazabicyco octane), ascorbate or reduced glutathione). Application of elsinochromes onto rough lemon leaves resulted in necrotic lesions, whereas lesion development was inhibited by the addition of bixin, DABCO or ascorbate, but not α -tocopherol. Incubation of rough lemon leaf discs with elsinochromes in the light induced a steady increase of electrolyte leakage.• Compared with two photosensitizing compounds, hematoporphyrin and cercosporin, the accumulation of 1 O 2 induced by elsinochromes after irradiation was indicated by successful detection of the cholesterol oxidation product, 5 α -hydroperoxide. Addition of a potent quencher, β -carotene prevented 5 α -hydroperoxide production. Elsinochromes generated superoxide ions ( ), whereas accumulation of was blocked by addition of the superoxide dismutase, a scavenger of , but not the 1 O 2 -quencher, DABCO. Our study indicated that elsinochromes are functioning as photosensitizing compounds that produce 1 O 2 and , and exert toxicity to plant cells.

Background. Chinese herbal medicine Dingji Fumai Decoction (DFD) is widely clinically used for ventricular premature contraction (VPC). This real-word trial was designed to assess the safety and effectiveness of DFD for VPC. Methods. This was a double-blinded, randomized placebo-controlled trial. Patients with VPC were randomized (1 : 1) to treatment with DFD combined with metoprolol (DFD arm) or metoprolol combined with placebo (MET arm). A primary end point was a composite of clinical symptoms and signs determined by the traditionalChinese medicine syndrome score and the number of VPC determined by the Holter examination. Second outcomes were adverse events, medication compliance, and laboratory examination. Results. 144 patients were randomized to DFD arm (76 patients) or MET arm (68 patients), and 136 cases (71 in DFD arm and 65 in MET arm) finally completed this trial. After a 12-week follow-up, DFD arm significantly decreased traditional Chinese medicine syndrome score and the number of VPC compared with MET arm (P=0.003 and 0.034, respectively). There was no adverse drug effect and patient medication compliance was good. Conclusions. Superiority with DFD arm for VPC was demonstrated over MET arm for both the safety and effectiveness end points.

Under the current NHI system, patients with multiple chronic diseases are the major purchasers of TCM products not covered by NHI. Therefore, increasing the usable resources of TCM products for the patients with chronic diseases will help hospitals in developing TCM services under the current NHI system.

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Objective: The stratification of neuroblastoma (NBL) prognosis remains difficult. RNA-based signatures might be able to predict prognosis, but independent cross-platform validation is still rare.Methods: RNA-Seq-based profiles from NBL patients were acquired and then analyzed. The RNA-Seq prognostic index (RPI) and the clinically adjusted RPI (RCPI) were successively established in the training cohort (TARGET-NBL) and then verified in the validation cohort (GSE62564). Survival prediction was assessed using a time-dependent receiver operating characteristic (ROC) curve and area under the ROC curve (AUC). Functional enrichment analysis of the genes was conducted using bioinformatics methods.Results: In the training cohort, 10 gene pairs were eventually integrated into the RPI. In both cohorts, the high-risk group had poor overall survival (OS) (P < 0.001 and P < 0.001, respectively) and favorable event-free survival (EFS) (P = 0.00032 and P = 0.06, respectively). ROC curve analysis also showed that the RPI predicted OS (60 month AUC values of 0.718 and 0.593, respectively) and EFS (60 month AUC values of 0.627 and 0.852, respectively) well in both the training and validation cohorts. Clinicopathological indicators associated with prognosis in the univariate and multivariate regression analyses were identified and added to the RPI to form the RCPI. The RCPI was also used to divide populations into different risk groups, and the high-risk group had poor OS (P < 0.001 and P < 0.001, respectively) and EFS (P < 0.05 and P < 0.05, respectively). Finally, the RCPI had higher accuracy than the RPI for the prediction of OS (60 month AUC values of 0.730 and 0.852, respectively) and EFS (60 month AUC values of 0.663 and 0.763, respectively) in both the training and validation cohorts. Moreover, these differentially expressed genes may be involved in certain NBL-related events.Conclusions: The RCPI could reliably categorize NBL patients based on different risks of death.