Search

In this review, we summarise the current knowledge on three pathogens that exhibit distinct tissue specificity and modes of pathogenesis in citrus plants. Xanthomonas axonopodis pv . citri causes canker disease and invades the host leaf mesophyll tissue through natural openings and can also survive as an epiphyte. Xylella fastidiosa and Candidatus Liberibacter are vectored by insects and proliferate in the vascular system of the host, either in the phloem ( Candidatus Liberibacter) or xylem ( X. fastidiosa) causing variegated chlorosis and huanglongbing diseases, respectively. Candidatus Liberibacter can be found within host cells and is thus unique as an intracellular phytopathogenic bacterium. Genome sequence comparisons have identified groups of species-specific genes that may be associated with the particular lifestyle, mode of transmission or symptoms produced by each phytopathogen. In addition, components that are conserved amongst bacteria may have diverse regulatory actions underpinning the different bacterial lifestyles; one example is the divergent role of the Rpf/DSF cell–cell signalling system in X. citri and X. fastidiosa. Biofilm plays a key role in epiphytic fitness and canker development in X. citri and in the symptoms produced by X. fastidiosa. Bacterial aggregation may be associated with vascular occlusion of the xylem vessels and symptomatology of variegated chlorosis. [ABSTRACT FROM AUTHOR]

Obesity is a growing concern world wide, due to the progressive raise of overweight individuals, particularly adolescents, and due to its health consequences. A descriptive correlational study was conducted with the aim of determining the prevalence of obesity among high school students and its relation with some factors. A non probability sample is constituted by 197 students drawn from two high schools of the district of Coimbra. The results showed, according to the classification of obesity recommended by the Direcção Geral de Saúde (2005) a prevalence of obese individuals of 3,55% and 10,15% of overweight students. The influence of age, sex and physical activity on the percentage of the students' fat mass was statistically confirmed. There was a statistically significant relation between the BMI of the students and their respective parents. [ABSTRACT FROM AUTHOR]

Information and Communication Technology (ICT) Governance is increasingly necessary and present in organizations aiming to improve the maturity of their ICT processes. This paper presents an analysis of the ICT Governance processes of a Brazilian Federal Public Administration agency. To assess the maturity of the ICT Governance processes, we surveyed and diagnosed the processes performed by the agency and organized a series of meetings/discussions to assist in the improvement and modeling of the processes related to the ICT Contract Planning process. As a result, we proposed improvements and identified the maturity level of the existing ICT processes, also assessing the awareness of employees of the General Coordination of Information Technology regarding these processes. Our findings reveal that the agency still needs to implement the following processes: (1) ICT People Management; (2) Business Process Modeling (Automated/to Automate); (3) Change Management; (4) Execution Monitoring of the ICT Projects and Services Portfolio; and (5) ICT Service Continuity Management. We also identified several artifacts that need to be implemented by the agency in different processes and collected survey participants' suggestions about new processes to improve the maturity in ICT Governance. [ABSTRACT FROM AUTHOR]

Objective: analyze the publications of Twitter users directed to the campaign of valuation of Nursing, driven by the terms #LuteComoUmaEnfermeira and #EnfermagemEuValorizo. Method: quantitative research, based on digital methods. The search was realized using the hashtags #LuteComoUmaEnfermeira and #EnfermagemEuValorizo for tweets extraction. 2,613 tweets were selected for analysis. Results: 22.5% of publications are located in the Brazilian Southeast region and 9.3% in the Northeast region. There were more than 18,000 interactions (likes and shares), and the authors of the posts reach an estimated audience of about 7 million people). The content of the posts mainly related to the regulation of working hours, Personal Protective Equipment, the fight against COVID-19, the defense of the majority female workforce and the fight for rights. Conclusion: the realization of the virtual campaign had important visibility in the national territory and presented great visibility to the profession in number and reach on the Internet. [ABSTRACT FROM AUTHOR]

Xanthomonas citri ssp. citri ( Xcc) is the causal agent of citrus canker. This bacterium develops a characteristic biofilm on both biotic and abiotic surfaces. A biofilm-deficient mutant was identified in a screening of a transposon mutagenesis library of the Xcc 306 strain constructed using the commercial Tn 5 transposon EZ- Tn 5 < KAN-2> Tnp Transposome ( Epicentre). Sequence analysis of a mutant obtained in the screening revealed that a single copy of the EZ- Tn 5 was inserted at position 446 of hrp M, a gene encoding a putative enzyme involved in glucan synthesis. We demonstrate for the first time that the product encoded by the hrp M gene is involved in β-1,2-glucan synthesis in Xcc. A mutation in hrp M resulted in no disease symptoms after 4 weeks of inoculation in lemon and grapefruit plants. The mutant also showed reduced ability to swim in soft agar and decreased resistance to H2 O2 in comparison with the wild-type strain. All defective phenotypes were restored to wild-type levels by complementation with the plasmid p BBR1- MCS containing an intact copy of the hrp M gene and its promoter. These results indicate that the hrp M gene contributes to Xcc growth and adaptation in its host plant. [ABSTRACT FROM AUTHOR]

Background: Citrus Bacterial Canker (CBC) is a major, highly contagious disease of citrus plants present in many countries in Asia, Africa and America, but not in the Mediterranean area. There are three types of Citrus Bacterial Canker, named A, B, and C that have different genotypes and posses variation in host range within citrus species. The causative agent for type A CBC is Xanthomonas citri subsp. citri, while Xanthomonas fuscans subsp. aurantifolii, strain B causes type B CBC and Xanthomonas fuscans subsp. aurantifolii strain C causes CBC type C. The early and accurate identification of those bacteria is essential for the protection of the citrus industry. Detection methods based on bacterial isolation, antibodies or polymerase chain reaction (PCR) have been developed previously; however, these approaches may be time consuming, laborious and, in the case of PCR, it requires expensive laboratory equipment. Loop-mediated isothermal amplification (LAMP), which is a novel isothermal DNA amplification technique, is sensitive, specific, fast and requires no specialized laboratory equipment. Results: A loop-mediated isothermal amplification assay for the diagnosis of Citrus Bacterial Canker (CBC-LAMP) was developed and evaluated. DNA samples were obtained from infected plants or cultured bacteria. A typical ladder-like pattern on gel electrophoresis was observed in all positive samples in contrast to the negative controls. In addition, amplification products were detected by visual inspection using SYBRGreen and using a lateral flow dipstick, eliminating the need for gel electrophoresis. The sensitivity and specificity of the assay were evaluated in different conditions and using several sample sources which included purified DNA, bacterium culture and infected plant tissue. The sensitivity of the CBC-LAMP was 10 fg of pure Xcc DNA, 5 CFU in culture samples and 18 CFU in samples of infected plant tissue. No cross reaction was observed with DNA of other phytopathogenic bacteria. The assay was capable of detecting CBC-causing strains from several geographical origins and pathotypes. Conclusions: The CBC-LAMP technique is a simple, fast, sensitive and specific method for the diagnosis of Citrus Bacterial Canker. This method can be useful in the phytosanitary programs of the citrus industry worldwide. [ABSTRACT FROM AUTHOR]