Picolinic acid spray stimulates the antioxidative metabolism and minimizes impairments on photosynthesis on wheat leaves infected by Pyricularia oryzae.

Fungal pathogens produce toxins that are important for their pathogenesis and/or aggressiveness towards their hosts. Picolinic acid (PA), a non-host selective toxin, causes lesions on rice leaves resembling those originated from Pyricularia oryzae infection. Considering that non-host selective toxins can be useful for plant diseases control, this study investigated whether the foliar spray with PA on wheat (Triticum aestivum L.) plants, in a non-phytotoxic concentration, could increase their resistance to blast, stimulate the anti-oxidative metabolism, and minimize alterations in photosynthesis. The PA spray at concentrations greater than 0.1 mg ml-1 caused foliar lesions, compromised the photosynthesis and was linked with greater accumulation of hydrogen peroxide (H2 O2 ) and superoxide anion radical (O2 •- ). Fungal mycelial growth, conidia production and germination decreased by PA at 0.3 mg ml-1 . Blast severity was significantly reduced by 59 and 23%, respectively, at 72 and 96 h after inoculation for plants sprayed with PA (0.1 mg ml-1 ) at 24 h before fungal inoculation compared to non-sprayed plants. Reduction on blast symptoms was linked with increases on ascorbate peroxidase (EC 1.11.1.11), catalase (EC 1.11.1.6), glutathione peroxidase (EC 1.11.1.9), glutathione reductase (EC 1.8.1.7), glutathione-S-transferase (EC 2.5.1.18), peroxidase (EC 1.11.1.7), and superoxide dismutase (EC 1.15.1.1) activities, lower H2 O2 and O2 •- accumulation, reduced malondialdehyde production as well as less impairments to the photosynthetic apparatus. A more efficient antioxidative metabolism that rapidly scavenges the reactive oxygen species generated during P. oryzae infection, without dramatically decreasing the photosynthetic performance, was a remarkable effect obtained with PA spray.

Detection of human mammaglobin mRNA in serial peripheral blood samples from patients with non-metastatic breast cancer is not predictive of disease recurrence.

INTRODUCTION: Human mammaglobin (hMAM) mRNA is a sensitive and specific marker of breast cancer cells. We evaluated if hMAM mRNA detection in serial peripheral blood samples from non-metastatic breast cancer patients predicts for disease recurrence. METHODS: Patients scheduled for adjuvant or neoadjuvant chemotherapy were eligible. Serial blood samples were collected up to 5 years, the first before (neo)adjuvant chemotherapy. hMAM gene expression was analysed by RT-PCR. Specificity was evaluated in blood samples from healthy volunteers. A total of 321 patients were included. RESULTS: The incidence of pre-chemotherapy hMAM-positive samples was similar in patients who latter experienced cancer recurrence (22.4%) and those who remained disease-free (17.9%; P = 0.46). Similarly, the mean number of positive follow-up samples was similar in both groups (0.15 +/- 0.22 and 0.13 +/- 013; P = 0.29). Furthermore, there was no difference in disease-free (P = 0.63) or overall survival (P = 0.57) in patients with and without positive baseline samples or between patients whose follow-up samples were always hMAM negative and those with at least one positive sample. Multivariate survival analysis confirmed that hMAM mRNA detection before or after (neo)adjuvant chemotherapy was not predictive of recurrence. DISCUSSION: There is no evidence that hMAM mRNA detection at diagnosis or during follow-up predicts for breast cancer recurrence.

Long-term follow-up of lymphocyte populations and cellular cytokine production in patients with chronic graft-versus-host disease treated with extracorporeal photopheresis.

We studied lymphocyte populations and cytokine-expression profiles of ten patients with chronic graft-versus-host disease who at least transiently responded to photoimmunotherapy. The numbers of lymphocytes, monocytes and dendritic cells rose in most cases. Th1 cells always increased during therapy, supporting the hypothesis that a more favorable immune balance contributes to clinical responses.