Irrigation Targeted to Provoke Ejection of Ascospores of Venturia inaequalis Shortens the Season for Ascospore Release and Results in Less Apple Scab.

Trials were carried out in apple orchards of Emilia-Romagna and Trentino-Alto Adige in northern Italy to investigate the effects of sprinkler irrigation on possible reduction in inoculum and subsequent disease pressure of Venturia inaequalis, the ascomycete causing apple scab. In spring, volumetric spore traps were placed above apple leaf litter containing pseudothecia with ascospores of the fungus. Pseudothecia matured more rapidly in irrigated plots, and 95% of the total number of spores trapped in a season was reached on average 164 degree days (base temperature 0°C) earlier in irrigated compared to non-irrigated plots. On average for seven location/year combinations, more than 50% of the ascospores were trapped following irrigations carried out for two hours on sunny days before a forecasted rainfall. Subsequently, a much lower number of spores were trapped on rainy days following irrigation. Field trials with scab susceptible apple cultivars were carried out in the two regions to evaluate the efficacy of sprinkler irrigation on disease. Irrigated and non-irrigated plots were either treated with different fungicide control strategies or not treated. Irrigation significantly reduced the incidence of apple scab at both sites, and the overall number of infected leaves and fruit was reduced by more than 50%. Mid-day sprinkler irrigation can significantly reduce the inoculum pressure of V. inaequalis in apple orchards. This may be a sustainable management strategy, especially in areas with extended dry periods.

Epigenetic Contribution of High-Mobility Group A Proteins to Stem Cell Properties.

High-mobility group A (HMGA) proteins have been examined to understand their participation as structural epigenetic chromatin factors that confer stem-like properties to embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), and cancer stem cells (CSCs). The function of HMGA was evaluated in conjunction with that of other epigenetic factors such as histones and microRNAs (miRs), taking into consideration the posttranscriptional modifications (PTMs) of histones (acetylation and methylation) and DNA methylation. HMGA proteins were coordinated or associated with histone and DNA modification and the expression of the factors related to pluripotency. CSCs showed remarkable differences compared with ESCs and iPSCs.

The expression of the high-mobility group A2 protein in colorectal cancer and surrounding fibroblasts is linked to tumor invasiveness.

Tumor staging of colorectal cancer is typically based on conventional TNM and Dukes classifications. However, additional information could be useful, and there is a significant interest in identifying molecular markers that are related to genetic or epigenetic processes. Using immunohistochemistry, we analyzed the expression of the high-mobility group A2 (previously high-mobility group 1-C [HMGI-C]) protein in 103 colorectal cancer cases to determine its use as a biomarker in colorectal cancer to integrate morphological staging. We found a progressive increase of the high-mobility group A2 protein expression in colorectal cancer tumor samples from cases in which all of the tumor cells were negative up to cases in which all of the tumor cells stained positive. Increased high-mobility group A2 expression is strongly associated with an increase in tumor invasiveness, which was measured through both budding and vascular invasion (P < .0001). Kaplan-Meier estimates showed a decrease in overall survival when vascular invasion is present (P = .023). Moreover, a fraction of the analyzed samples showed high-mobility group A2-positive stromal fibroblasts. Although high-mobility group A2-positive tumors were associated with cell invasiveness, high-mobility group A2-positive stromal fibroblasts were correlated with less invasive tumors. High-mobility group A2 protein expression could be used as a prognostic marker to provide prospective information on patient outcome, complementing the data obtained using conventional pathologic staging systems.

Leukocytoclastic vasculitis in urticaria induced by sun exposure.

BACKGROUND: Solar urticaria manifests itself immediately after solar or artificial light exposure and disappears a little later. Histopathologic findings of solar urticaria are essentially identical to those of classic urticaria. CASE REPORT: We report a 41-year-old man who developed urticarial lesions some hours after sunlight exposure, which resolved after approximately 1 week. Histologic examination of the lesions evidenced a leukocytoclastic vasculitis. CONCLUSION: In a literature review we found one case of solar urticaria with histologic aspects of leukocytoclastic vasculitis.