Fungicidal Activity of Plant Volatile Compounds for Controlling Monilinia laxa in Stone Fruit.

Nine plant-volatile compounds were tested for their activity against Monilinia laxa, the cause of brown rot in stone fruit. In vitro trials on conidial germination and mycelial growth showed a consistent fungicidal activity of trans-2-hexenal, carvacrol, and citral, whereas trans-cinnamaldehyde, hexanal, (-)-carvone, eugenol, 2-nonanone, and p-anisaldehyde exhibited a progressively lower inhibition. The best inhibitor of conidial germination was trans-2-hexenal (effective dose for 50 and 90% inhibition [ED50 and ED95] = 7.53 and 9.4 µl/liter, respectively; minimal inhibitory concentration [MIC] = 12.3 µl/liter], whereas carvacrol was the best inhibitor of mycelial growth (ED50 and ED95 = 2 and 3.4 µl/liter, respectively; MIC = 6.1 µl/liter). The three most active compounds in in vitro studies also were tested in vivo as postharvest biofumigants. The best control of brown rot was with trans-2-hexenal (efficacy ranging from 46.2 to 80.3%, depending on cultivar), whereas citral and carvacrol resulted in a lower efficacy of 40 and 32.9%, respectively. Fumigation with trans-2-hexenal at concentrations that stopped decay did not cause any visible disorders to plum, whereas it was phytotoxic to apricot, peach, and nectarine and produced off-odors or off-flavors in all species of stone fruit tested.

Polyphenols Variation in Fruits of the Susceptible Strawberry Cultivar Alba during Ripening and upon Fungal Pathogen Interaction and Possible Involvement in Unripe Fruit Tolerance.

Strawberry (Fragaria × ananassa) fruit contains high concentrations of health-promoting phenolic compounds, playing important roles for the fruit ontogenic tolerance to fungi. In the highly susceptible cultivar Alba, the two major strawberry fungal pathogens, Colletotrichum acutatum and Botrytis cinerea, displayed disease symptoms only at red ripe stages because immature fruits are tolerant to diseases. We analyzed and compared the variation of 47 polyphenols in the surface of unripe and ripe Alba fruits upon 24 and 48 h of C. acutatum and B. cinerea infection or mock inoculation. Significant alteration in phenolic content was detected only in white infected fruit, with differences specific for each pathogen. The expression analysis of phenylpropanoid, flavonoid, and shikimate pathway genes showed in only a few cases correlation with the relative metabolite abundance. The alteration in phenolic content and the lack of consistency with gene expression data are discussed in light of previously reported metabolome data of different susceptible and resistant strawberry genotypes.

The mannose-binding lectin gene FaMBL1 is involved in the resistance of unripe strawberry fruits to Colletotrichum acutatum.

The fungal pathogen Colletotrichum acutatum is the causal agent of strawberry (Fragaria × ananassa) anthracnose. Although the fungus can infect strawberry fruits at both unripe and ripe stages, the symptoms appear only on red ripe fruits. On white unripe fruits, the pathogen becomes quiescent as melanized appressoria after 24 h of interaction. Previous transcriptome analysis has indicated that a mannose-binding lectin (MBL) gene is the most up-regulated gene in 24-h-infected white strawberries, suggesting a role for this gene in the low susceptibility of unripe stages. A time course analysis of the expression of this MBL gene, named FaMBL1 (Fragaria × ananassa MBL 1a), was undertaken to monitor its expression profile in white and red fruits at early interaction times: FaMBL1 was expressed exclusively in white fruit after 24 h, when the pathogen was quiescent. Agrobacterium-mediated transient transformation was used to silence and overexpress the FaMBL1 gene in 24-h-infected white and red strawberries, respectively. FaMBL1-silenced unripe fruits showed an increase in susceptibility to C. acutatum. These 24-h-infected tissues contained subcuticular hyphae, indicating pathogen penetration and active growth. In contrast, overexpression of FaMBL1 in ripe fruits decreased susceptibility; here, 24-h-infected tissues showed a high percentage of ungerminated appressoria, suggesting that the growth of the pathogen had slowed. These data suggest that FaMBL1 plays a crucial role in the resistance of unripe strawberry fruits to C. acutatum.

Leukocyte filtration ameliorates the inflammatory response in patients with mild to moderate lung dysfunction.

BACKGROUND: Chronic obstructive pulmonary disease is a risk factor for postoperative lung injury. Contradictory results have been published about leukocyte filtration (LF) because of the heterogeneity of patients and interventions, type of LF, and comorbidities. METHODS: Sixty patients with mild moderate chronic obstructive pulmonary disease (forced expiratory volume in 1 second 40% to 80%) undergoing aortic valve surgery were randomly assigned to receive systemic arterial and cardioplegic LF during cardiopulmonary bypass (group L, 30 patients) or standard cardiopulmonary bypass (group S). Perioperative interleukin-6, interleukin-8, and tumor necrosis factor-alpha were sampled at different time points. The PaO2/inspired oxygen fraction (FiO2) and alveoloarterial oxygen gradient (AaDO2) were measured preoperatively, at intensive care unit arrival, and at 24, 48, and 72 hours postoperatively; lung compliance was measured after intubation, at intensive care unit arrival, and at 4 and 8 hours postoperatively; and radiographic lung injury score was determined preoperatively and at 24, 48 and 72 hours. Length of intubation, intensive care unit stay, hospital stay, need for noninvasive positive-pressure ventilation, acute lung injury, and pneumonia were recorded. Repeated-measures analysis of variance assessed group, time, and group by-time interactions. RESULTS: Preoperative and intraoperative data were comparable. Proinflammatory cytokine leakage was reduced by LF. Group L showed shorter intubation time (median 9.5 hours versus group S, 15.0 hours; p=0.0001), and intensive care unit length of stay (median 19.0 hours versus group S, 24.5; p=0.0001), lower need for noninvasive positive-pressure ventilation (5 of 30, 16.7%, versus 12 of 30, 40%; p=0.042). The AaDO2, PaO2/FiO2, lung compliance, and radiographic lung injury score worsened early postoperatively, followed by progressive improvements (time p≤0.001 for all). Such decline of AaDO2, PaO2/FiO2, lung compliance, and radiographic lung injury score was significantly attenuated by LF (group by-time p=0.0001 for AaDO2, PaO2/FiO2, and lung compliance; p=0.004 for radiographic lung injury score). CONCLUSIONS: Arterial plus cardioplegic LF significantly reduced proinflammatory cytokine release after cardiopulmonary bypass, thus ameliorating postoperative indexes of lung function and overall respiratory outcome.

The RNA hydrolysis and the cytokinin binding activities of PR-10 proteins are differently performed by two isoforms of the Pru p 1 peach major allergen and are possibly functionally related.

PR-10 proteins are a family of pathogenesis-related (PR) allergenic proteins playing multifunctional roles. The peach (Prunus persica) major allergen, Pru p 1.01, and its isoform, Pru p 1.06D, were found highly expressed in the fruit skin at the pit hardening stage, when fruits transiently lose their susceptibility to the fungal pathogen Monilinia spp. To investigate the possible role of the two Pru p 1 isoforms in plant defense, the recombinant proteins were expressed in Escherichia coli and purified. Light scattering experiments and circular dichroism spectroscopy showed that both proteins are monomers in solution with secondary structures typical of PR-10 proteins. Even though the proteins do not display direct antimicrobial activity, they both act as RNases, a function possibly related to defense. The RNase activity is different for the two proteins, and only that of Pru p 1.01 is affected in the presence of the cytokinin zeatin, suggesting a physiological correlation between Pru p 1.01 ligand binding and enzymatic activity. The binding of zeatin to Pru p 1.01 was evaluated using isothermal titration calorimetry, which provided information on the stoichiometry and on the thermodynamic parameters of the interaction. The structural architecture of Pru p 1.01 and Pru p 1.06D was obtained by homology modeling, and the differences in the binding pockets, possibly accounting for the observed difference in binding activity, were evaluated.

Early mitral deceleration and left atrial stiffness.

Left ventricular (LV) filling deceleration time (DT) is determined by the sum of atrial and ventricular stiffnesses (KLA + KLV). If KLA, however, is close to zero, then DT would reflect KLV only. The purpose of this study was to quantify KLA during DT. In 15 patients, KLV was assessed, immediately after cardiopulmonary bypass, from E wave DT as derived from mitral tracings obtained by transesophageal echocardiography and computed according to a validated formula. In each patient, a left atrial (LA) volume curve was also obtained combining mitral and pulmonary vein (PV) cumulative flow plus LA volume measured at end diastole. Time-adjusted LA pressure was measured simultaneously with Doppler data in all patients. KLA was then calculated during the ascending limb of the V loop and during DT. LA volume decreased by 7.3 +/- 6.5 ml/m2 during the first of mitral DT, whereas LV volume increased 9.4 +/- 8.4 ml/m2 (both P < 0.001). There was a small amount of blood coming from the PV during the same time interval, with the cumulative flow averaging 3.2 +/- 2.4 ml/m(2) (P < 0.001). Mean LA pressure was 10.0 +/- 5.1 mmHg, and it did not change during DT [from 7.8 +/- 4.3 to 8.0 +/- 4.3 mmHg, not significant (NS)], making KLA, which averaged 0.46 +/- 0.39 mmHg/ml during the V loop, close to zero during DT [KLA(DT): from -0.002 +/- 0.08 to -0.001 +/- 0.031 mmHg/ml, NS]. KLV, as assessed noninvasively from DT, averaged 0.25 +/- 0.32 mmHg/ml. In conclusion, notwithstanding the significant decrement in LA volume, KLA does not change and can be considered not different from zero during DT. Thus KLA does not affect the estimation of KLV from Doppler parameters.