Role of methyl jasmonate and salicylic acid in kiwifruit plants further subjected to Psa infection: biochemical and genetic responses.

The use of plant elicitors for controlling Pseudomonas syringae pv. actinidiae (Psa), the etiological agent of the kiwifruit bacterial canker (KBC), has been analysed in the past and, while salicylic acid (SA) seems to decrease disease susceptibility, methyl jasmonate (MJ) shows an opposite effect. However, the metabolic and genomic responses of Psa-infected plants following elicitation with these two compounds, as compared with non-elicited Psa-inoculated plants, are poorly understood, being the focus of this study. Micropropagated A. chinensis 'Hayward' plants were elicited with MJ or SA, and further inoculated with Psa. Fifteen days post-inoculation, Psa population in MJ-treated plants was increased by 7.4-fold, whereas SA elicitation led to decreased Psa colonization (0.5-fold), as compared with non-elicited inoculated plants. Additionally, elicitation with MJ or SA generally decreased polyphenols and lignin concentrations (by at least 20%) and increased total proteins (by at least 50%). MJ led to the upregulation of SOD, involved in plant antioxidant system, and reporter genes for the jasmonic acid (JA) (JIH and LOX1), abscisic acid (SnRK), SA (ICS1), and ethylene (ACAS1, ETR1 and SAM) pathways. Moreover, it increased ABA (40%) and decreased carotenoids (30%) concentrations. Contrastingly, comparing with non-elicited Psa-inoculated plants, SA application resulted in the downregulation of antioxidant system-related genes (SOD and APX) and of reporter genes for ethylene (ETR1) and JA (JIH and ETR1). This study contributes to the understanding of potential mechanisms involved in kiwifruit plant defences against Psa, highlighting the role of the JA, ABA and ethylene in plant susceptibility to the pathogen.

Early Pathogen Recognition and Antioxidant System Activation Contributes to Actinidia arguta Tolerance Against Pseudomonas syringae Pathovars actinidiae and actinidifoliorum.

Actinidia chinensis and A. arguta have distinct tolerances to Pseudomonas syringae pv. actinidiae (Psa), but the reasons underlying the inter-specific variation remain unclear. This study aimed to integrate the metabolic and molecular responses of these two kiwifruit species against the highly pathogenic Psa and the less pathogenic P. syringae pv. actinidifoliorum (Pfm) bacterial strains. Disease development was monitored weekly till 21 days post inoculation (dpi), analysing a broad number and variety of parameters including: colony forming units (CFU), foliar symptoms, total chlorophylls, lipid peroxidation, soluble polyphenols, lignin and defense-related gene expression. At the end of the experimental period A. chinensis inoculated with Psa presented the highest endophytic bacterial population, whereas A. arguta inoculated with Pfm showed the lowest values, also resulting in a lower extent of leaf symptoms. Metabolic responses to infection were also more pronounced in A. chinensis with decreased total chlorophylls (up to 55%) and increased lipid peroxidation (up to 53%), compared with non-inoculated plants. Moreover, at 14 dpi soluble polyphenols and lignin concentrations were significantly higher (112 and 26%, respectively) in Psa-inoculated plants than in controls, while in A. arguta no significant changes were observed in those metabolic responses, except for lignin concentration which was, in general, significantly higher in Psa-inoculated plants (by at least 22%), comparing with control and Pfm-inoculated plants. Genes encoding antioxidant enzymes (SOD, APX and CAT) were upregulated at an earlier stage in Psa-inoculated A. arguta than in A. chinensis. In contrast, genes related with phenylpropanoids (LOX1) and ethylene (SAM) pathways were downregulated in A. arguta, but upregulated in A. chinensis in the later phases of infection. Expression of Pto3, responsible for pathogen recognition, occurred 2 dpi in A. arguta, but only 14 dpi in A. chinensis. In conclusion, we found that A. arguta is more tolerant to Psa and Pfm infection than A. chinensis and its primary and secondary metabolism is less impacted. A. arguta higher tolerance seems to be related with early pathogen recognition, the activation of plant antioxidant system, and to the suppression of ET and JA pathways from an earlier moment after infection.

[Role of arterial hypertension in comorbidity of chronic headaches]. / El papel de la hipertensión arterial en la comorbilidad de las cefaleas crónicas.

INTRODUCTION: The literature concerning the association between headache and arterial hypertension is very scarce, mostly prior to the actual IHS classification and based on very diverse methods, being therefore difficult to interpret. OBJECTIVES: To analyse the association between arterial hypertension and two types of chronic headache and to determine, if and how arterial hypertension may affect the outcome of prophylactic therapy for chronic headaches. PATIENTS AND METHODS: Sixty four files of our headache outpatient clinic, chosen randomly among patients suffering from migraine or tensional type headache (TTH), were analysed retrospectively. Patients were considered hypertensive, if blood pressure was higher than normal several times without an acute crisis present. Resistance to treatment was defined as lack of benefit concerning number and/or intensity of crisis. RESULTS: Age varied between 18 and 80 years, the mean age being 42,9 (SD 13,86) years. Eighty six percent were females. Twenty nine patients suffered from TTH and 35 from migraine. Prevalence of hypertension was 35,9% among all patients, 28,5% among migraine patients, 44,8% among patients with TTH. The prevalence of resistance to treatment was 39,8%, 34,3% and 41,3%, respectively. Of the patients resistant to treatment 60% were hypertensive and 62,5% of the hypertensive patients showed resistance to therapy. CONCLUSIONS: Arterial hypertension was more prevalent in the study sample than would be expected in an equivalent sample of the general population. Hypertension was significantly more prevalent among patients resistant to therapy, as was resistance to treatment among hypertensive patients. We therefore conclude that there is a relevant comorbidity between chronic headache and hypertension and that arterial hypertension complicates the control of chronic headaches.

[Headaches, otalgia and peripheral facial palsy as a form of presentation of neurosyphilis]. / Cefaleas, otalgias, hipoacusia y parálisis facial periférica como forma de presentación de la neurosífilis.

INTRODUCTION: Decrease in incidence of neurosyphilis over the last few decades implies that clinicians consider less frequently this diagnosis. On the other hand, some reports suggest an increase in atypical forms of this disease that represent an additional reason for missing this diagnosis. CLINICAL CASE: We report on a 16 year-old immunocompetent black female from Guinea-Bissau presented with headaches, ear pain, hearing loss and peripheral facial paralysis. A cranial CT scan showed a hypodense area in the left cortico-subcortical zone and a contrast enhancement on the left pontocerebellar angle and internal auditory meatus. On the third day of admission a diagnosis of meningitis was made, with high titles of VDRL and TPHA in CSF and serum, leading to a diagnosis of neurosyphilis. The epidemiological aspects of this case suggest either a late congenital syphilis or an infection as a result of a blood transfusion administered seven years earlier in Guinea-Bissau. CONCLUSION: This rare form of presentation of neurosyphilis emphasizes the importance of considering systematically this diagnosis, even in the context of atypical presentations.