1,271 research outputs found

    Leaf morphological characteristics and stilbene production differently affect downy mildew resistance of Vitis vinifera varieties grown in Italy

    Get PDF
    The degree of resistance to downy mildew of grape varieties belonging to the oenological tradition of Central Italy was evaluated by the analysis of plant responses to pathogen infections carried out in natural and controlled environments. Leaf morphological traits, such as hair and stornata! density, were determined for each variety, and the percentage of infected stornata and pathogen colonization of host mesophyll at 24, 48, and 72 hours post inoculation were assessed by epifluorescence microscopy. Furthermore, stilbene production at the site of Plasmopara viticola infection was analyzed at 72 hours post inoculation. Results indicate differences in resistance to downy mildew among selected varieties. Different significant values were detected among grapevines in the percentage of infected stornata and average number of successfully penetrated zoospores per stornata and per leaf surface unit. Differences also emerged in the rate of pathogen growth and stilbene production, signifying that defence mechanisms involved or induced during pathogen infection could be differentially effective among grapevine cultivars in limiting disease progression.Peer reviewe

    Ex vivo innate immune cytokine signature of enhanced risk of relapsing brucellosis.

    Get PDF
    BackgroundBrucellosis, a zoonotic infection caused by one of the Gram-negative intracellular bacteria of the Brucella genus, is an ongoing public health problem in Perú. While most patients who receive standard antibiotic treatment recover, 5-40% suffer a brucellosis relapse. In this study, we examined the ex vivo immune cytokine profiles of recovered patients with a history of acute and relapsing brucellosis.Methodology/principal findingsBlood was taken from healthy control donors, patients with a history of acute brucellosis, or patients with a history of relapsing brucellosis. Peripheral blood mononuclear cells were isolated and remained in culture without stimulation or were stimulated with a panel of toll-like receptor agonists or heat-killed Brucella melitensis (HKBM) isolates. Innate immune cytokine gene expression and protein secretion were measured by quantitative real-time polymerase chain reaction and a multiplex bead-based immunoassay, respectively. Acute and relapse patients demonstrated consistently elevated cytokine gene expression and secretion levels compared to controls. Notably, these include: basal and stimulus-induced expression of GM-CSF, TNF-α, and IFN-γ in response to LPS and HKBM; basal secretion of IL-6, IL-8, and TNF-α; and HKBM or Rev1-induced secretion of IL-1β, IL-2, GM-CSF, IFN-Υ, and TNF-α. Although acute and relapse patients were largely indistinguishable by their cytokine gene expression profiles, we identified a robust cytokine secretion signature that accurately discriminates acute from relapse patients. This signature consists of basal IL-6 secretion, IL-1β, IL-2, and TNF-α secretion in response to LPS and HKBM, and IFN-γ secretion in response to HKBM.Conclusions/significanceThis work demonstrates that informative cytokine variations in brucellosis patients can be detected using an ex vivo assay system and used to identify patients with differing infection histories. Targeted diagnosis of this signature may allow for better follow-up care of brucellosis patients through improved identification of patients at risk for relapse

    Hacia un modelo teórico explicativo de la innovación en los distritos de turismo cultural

    Get PDF
    This paper presents a theoretical model that analyses the direct effect of social capital on innovation, as well as the mediating effect of acquisition of knowledge between both variables in firms in a cultural tourist district. We analyse the bidimensional nature of social capital —bonded capital and bridging capital—. It is an approach to the context and characteristics of cultural tourist districts. We point out several future investigation lines related to the differentiation between types of knowledge and innovation. We propose recommendations about the orientation of relations between companies and institutions of cultural tourist districts.En este trabajo se plantea un modelo teórico que analiza el efecto directo, y mediado por la adquisición de conocimiento, del capital social sobre la innovación desarrollada por las empresas pertenecientes a un distrito turístico cultural. Se analiza el carácter bidimensional del capital social —bonded capital y bridging capital—. Se realiza una aproximación al contexto y las caracteristicas de los distritos turísticos culturales. Se establecen diversas líneas futuras de trabajo vinculadas a la diferenciación entre tipos de conocimiento y de innovación. Se proponen recomendaciones sobre la orientación de las relaciones entre las empresas y con las instituciones de los distritos turísticos culturales

    Organisational Culture and Workplace Corruption in Government Hospitals

    Get PDF
    This study examines corruption attitudes and norms in government hospitals in the Philippines. It tests a culture-building model that advocates communication of desired values, leadership role modelling, employee role modelling, alignment of systems and structures, training and evaluation, and reinforcement. Results reveal components that influence corruption attitudes and norms. Communication predicted individual attitudes or acceptability of corrupt acts. Leadership, systems, and controls predicted the prevalence of corrupt acts. Employee role modelling predicted both acceptability of and the prevalence of corrupt acts. In addition, there is a positive relationship between individual attitudes and organisation norms reinforcing the dyadic relationship between the two

    The threat of the ambrosia beetle Megaplatypus mutatus (Chapuis) (=Platypus mutatus Chapuis) to world poplar resources

    Get PDF
    We describe the life cycle of Megaplatypus mutatus (Chapuis) (=Platypus mutatus) and the damage it causes to poplar resources in Argentina. This insect, native to the subtropical and tropical areas of South America, has extended its range into temperate regions, reaching as far south as Neuquén in Argentinean Patagonia. The damage is caused by the adult insects, which bore large gallery systems into living poplars (Populus spp.), willows (Salix spp.) and many other broadleaf species, including important fruit trees species such as apples (Malus spp.), walnuts (Juglans spp.) and avocados (Persea spp.). The galleries degrade the lumber and weaken the tree stems, which often then break during windstorms. A recent introduction of M. mutatus to Italy demonstrates that this insect can be transported long distances between countries, and therefore presents a threat worldwide - particularly to poplar cultivation. We review the taxonomic nomenclature for this pest, provide a summary of the life cycle, hosts and damage and summarize actions taken to reduce the risk of introduction of M. mutatus to Canada.Facultad de Ciencias Agrarias y Forestale

    Total fatty acid quantification as an estimator of total body fat content in broilers fed unsaturated diets

    Get PDF
    An experiment was designed to determine the effect of dietary fat unsaturation level on the fat content of the body of broilers, measured as hydrolysed crude fat (CF) and total fatty acid (TFA) content. Ninety-six female broiler chickens were fed with 4 experimental diets (with 15, 34, 45 and 61 g of polyunsaturated fatty acids (PUFA)/kg of diet) for 6 weeks. As dietary PUFA increased from 15 to 61 g PUFA/kg the fat content of the animals decrease was 55% and 15% when measured as CF and TFA content respectively. As we did not find any differences between treatments in crude protein (CP) and ashes (A) content, the total chemical composition (CF, CP and A as a percentage of Dry Matter (DM)) was close to 100% in the animals fed the saturated diets, reaching only 80% when the dietary unsaturation level was maximum. When using TFA instead of CF, the total chemical composition was close to 95% of DM in all treatments.Une expérience a été effectuée pour déterminer l'effet du niveau de la graisse insaturée dans l'aliment sur le contenu de la graisse corporelle des poulets mesuré par la teneur en graisse brute hydrolysée (CF) et par la teneur en acides gras totaux (TFA). Quatrevingt seize femelles broilers ont été alimentés avec 4 régimes expérimentaux (contenant 15, 34, 45 ou 61 g d'acides gras polyinsaturés (PUFA)/kg d'aliment) pendant six semaines. Quand la teneur en PUFA du régime augmente de 15 à 61 g/kg l'engraissement des animaux diminue de 55% et 15% quand il est mesuré par la teneur en CF et TFA respectivement. Comme on n'a pas trouvé de différences entre les traitements pour la teneur en protéines brutes (CP) et en cendres (A), la composition totale chimique (CF, CP et A exprimés en pourcentages de la matière 265 4 'i iHfnTT'ii Tli*nm I sèche (DM)) était près de 100% chez les animaux alimentés avec le régime riche en AG saturés, et seulement de 80% quand le niveau d'insaturation du régime était maximal. En utilisant le TFA au lieu de CF, la composition totale chimique était près de 95 % de la DM pour les 4 traitements
    corecore