Characterisation of the mating-type loci in species of Elsinoe causing scab diseases

The genus Elsinoe includes many aggressive plant pathogens that infect various economically important agricultural, horticultural and forestry plants. Significant diseases include citrus scab caused by E. fawcettii and E. australis, grapevine spot anthracnose by E. ampelina, and the emerging Eucalyptus scab and shoot malformation disease caused by the recently described E. necatrix. Despite their importance as plant pathogens, little is known regarding the biology of many Elsinoe spp. To gain insights into the reproductive biology of these fungi, we characterized the mating-type loci of seven species using whole genome sequence data. Results showed that the MAT1 locus organization and its flanking genes is relatively conserved in most cases. All seven species manifested a typical heterothallic mating system characterized by having either the MAT1-1 or MAT1-2 idiomorph present in an isolate. These idiomorphs were defined by the MAT1-1-1 or the MAT1-2-1 gene, respectively. A unique MAT1-1 idiomorph containing a truncated MAT1-2-1 gene, and a MAT1-1-1 gene, was identified in E. necatrix and E. fawcettii genomes. Additionally, two idiomorph-specific proteins were found in the MAT1-1 and MAT1-2 idiomorphs of E. australis. Universal mating-type markers confirmed heterothallism across 21 Elsinoe spp., are poised to advance future studies regarding the biology of these fungi.

Phytophthora acaciivora sp. nov. associated with dying Acacia mangium in Vietnam

Acacia mangium plantations account for more than 50 % of the exotic plantations in Vietnam. A new black butt symptom was discovered in 2012, followed by the wilting sign in Acacia seedlings in Tuyen Quang Province. Isolations recovered two Phytophthora species, the well-known Acacia pathogen P. cinnamomi, and an unknown species. The new species is described here as Phytophthora acaciivora sp. nov. Phylogenetically this species resides in clade 2d and is most closely related to P. frigida. Phytophthora acaciivora is a heterothallic species, oospores are aplerotic and antheridia are amphigynous. It produces predominantly elongated ovoid, semi papillate, persistent sporangia, no hyphal swellings and no chlamydospores. Optimum temperature for the growth is 25-30 °C and the maximum temperature is over 37.5 °C. Studies are underway to determine the impact of this new species on Acacia plantations in Vietnam.

Interferon and ribavirin for patients with chronic hepatitis C who did not respond to previous interferon therapy: a meta-analysis of controlled and uncontrolled trials

The efficacy of interferon (IFN) combined with ribavirin for the treatment of patients with hepatitis C who failed to respond to initial IFN therapy is not well established. The primary goal of this study was to perform a systematic review of the literature evaluating the efficacy of combination therapy in nonresponders. Studies were retrieved from MEDLINE, abstracts of scientific meetings, and review of the bibliographies of retrieved studies. Controlled trials were included in the primary analysis whereas uncontrolled trials and trials reported as abstracts were included for sensitivity analysis. The primary endpoints were biochemical and virologic response. A combined estimate of the odds ratio (OR) for each endpoint was obtained by using the random effects model. The number needed to treat (NNT) was calculated by taking the inverse of the pooled risk difference. Nine controlled trials (789 patients) were identified. Six months after treatment, the overall sustained biochemical and virologic responses to 24 weeks of combination therapy were 15.2% and 13.2% with a common OR of 3.8 (95% confidence interval [CI] 2.2-6.7) and 4.9 (95% CI 2.1-11.2) compared with patients treated with IFN monotherapy. The pooled risk difference for the sustained virologic response (SVR) to combination therapy was 7% (95% CI 2-13). The NNT was 14 (95% CI 8-50), suggesting that approximately 14 patients would need to be treated with 6 months of combination therapy for 1 patient to have a SVR. A number of variables were associated with a high response rate in individual studies. Sensitivity analysis of preliminary trials suggest a higher response rate with longer duration of therapy and non-type 1 genotypes.