Identification of salicylic acid-independent responses in an Arabidopsis phosphatidylinositol 4-kinase beta double mutant.

BACKGROUND AND AIMS: We have recently shown that an Arabidopsis thaliana double mutant of type III phosphatidylinositol-4-kinases (PI4Ks), pi4kß1ß2, constitutively accumulated a high level of salicylic acid (SA). By crossing this pi4kß1ß2 double mutant with mutants impaired in SA synthesis (such as sid2 impaired in isochorismate synthase) or transduction, we demonstrated that the high SA level was responsible for the dwarfism phenotype of the double mutant. Here we aimed to distinguish between the SA-dependent and SA-independent effects triggered by the deficiency in PI4Kß1 and PI4Kß2. METHODS: To achieve this we used the sid2pi4kß1ß2 triple mutant. High-throughput analyses of phytohormones were performed on this mutant together with pi4kß1ß2 and sid2 mutants and wild-type plants. Responses to pathogens, namely Hyaloperonospora arabidopsidis, Pseudomonas syringae and Botrytis cinerea, and also to the non-host fungus Blumeria graminis, were also determined. Callose accumulation was monitored in response to flagellin. KEY RESULTS: We show here the prominent role of high SA levels in influencing the concentration of many other tested phytohormones, including abscisic acid and its derivatives, the aspartate-conjugated form of indole-3-acetic acid and some cytokinins such as cis-zeatin. We show that the increased resistance of pi4kß1ß2 plants to the host pathogens H. arabidopsidis, P. syringae pv. tomato DC3000 and Bothrytis cinerea is dependent on accumulation of high SA levels. In contrast, accumulation of callose in pi4kß1ß2 after flagellin treatment was independent of SA. Concerning the response to Blumeria graminis, both callose accumulation and fungal penetration were enhanced in the pi4kß1ß2 double mutant compared to wild-type plants. Both of these processes occurred in an SA-independent manner. CONCLUSIONS: Our data extensively illustrate the influence of SA on other phytohormone levels. The sid2pi4kß1ß2 triple mutant revealed the role of PI4Kß1/ß2 per se, thus showing the importance of these enzymes in plant defence responses.

Glycerolipid analysis during desiccation and recovery of the resurrection plant Xerophyta humilis (Bak) Dur and Schinz.

Xerophyta humilis is a poikilochlorophyllous monocot resurrection plant used as a model to study vegetative desiccation tolerance. Dehydration imposes tension and ultimate loss of integrity of membranes in desiccation sensitive species. We investigated the predominant molecular species of glycerolipids present in root and leaf tissues, using multiple reaction monitoring mass spectrometry, and then analysed changes therein during dehydration and subsequent rehydration of whole plants. The presence of fatty acids with long carbon chains and with odd numbers of carbons were detected and confirmed by gas chromatography. Dehydration of both leaves and roots resulted in an increase in species containing polyunsaturated fatty acids and a decrease in disaturated species. Upon rehydration, lipid saturation was reversed, with this being initiated immediately upon watering in roots but only 12-24 hr later in leaves. Relative levels of species with short-chained odd-numbered saturated fatty acids decreased during dehydration and increased during rehydration, whereas the reverse trend was observed for long-chained fatty acids. X. humilis has a unique lipid composition, this report being one of the few to demonstrate the presence of odd-numbered fatty acids in plant phosphoglycerolipids.

Característica dos cateteres e de crianças portadoras de doença oncohematológica* / Characteristic of catheters and of children with oncohematological disease / Característica de los catéteresy de niños portadores de enfermedad onco-hematológica

O objetivo deste estudo foi identificar o perfil clínico de crianças/adolescentes com doença oncohematológica e as características dos cateteres utilizados por estes. Estudo descritivo, com abordagem quantitativa de 78 fichas de vigilância epidemiológica. O cenário foi um ambulatório de oncohematologia pediátrica, os dados foram coletados em agosto de 2015. Observou-se que 32 (59%) dos portadores de cateter totalmente implantado eram do sexo masculino, e sete (53%) dos portadores de cateter epicutâneo eram do sexo feminino, a idade variava entre 10 e 16 anos, o principal diagnóstico foi leucemia linfoide aguda em ambos. A média de utilização do cateter totalmente implantado foi 303 dias, enquanto do cateter epicutâneo foi 55 dias, o término do tratamento é o principal motivo de retirada de ambos. A falta de preenchimento de informações nas fichas foi limitador desta pesquisa. Concluímos que estes dispositivos são eficazes e seguros para tratamento quimioterápico (AU).

The objective in this study was to identify the clinical profile of children/adolescents with onco-hematological diseases and the characteristics of the catheters they use. Descriptive study with quantitative approach of 78 epidemiological surveillance forms. The scenario was a pediatric onco-hematology outpatient clinic. The data were collected in August 2015. It was observed that 32 (59%) of the patients using a totally implanted catheter were male, and seven (53%) patients with a peripherally inserted central venous catheter were female. Ages ranged between 10 and 16 years. The main diagnosis was acute lymphoid leukemia in both. The mean length of use of the totally implanted catheter was 303 days, against 55 days for the peripherally inserted central venous catheter. The end of the treatment is the main motive for the withdrawal of both. The lack of completed information in the forms limited this research. In conclusion, these devices are effective and safe for chemotherapeutic treatment (AU).

La finalidade del estudio fue identificar el perfil clínico de niños/adolescentes con enfermedad onco-hematológica, así como las características de los catéteres utilizados por ellos. Estudio descriptivo, con abordaje cuantitativo de 78 fichas de registro epidemiológicas. El contexto fue el de un ambulatorio de onco-hematología pediátrica y los datos fueron obtenidos en agosto de 2015. Se observó que 32 (59%) de los portadores de catéter totalmente implantado eran de sexo masculino, y que siete (53%) de los portadores de catéter epicutáneo eran de sexo feminino; la edad variaba entre 10 y 16 años; el diagnóstico principal fue el de leucemia linfoide aguda en ambos sexos. La media de utilización del catéter totalmente implantado fue de 303 días, mientras del catéter epicutáneo fue de 55 días; el término del tratamiento es el principal motivo de retirada de ambos. La falta de informaciones en las fichas de registro fue un factor limitador de esta investigación. Se concluye que estes dispositivos son eficaces y seguros para tratamiento quimioterápia (AU).