The Arabidopsis mutant eer2 has enhanced ethylene responses in the light

By screening for ethylene response mutants in Arabidopsis, a novel mutant, eer2, was isolated which displays enhanced ethylene responses. On a low nutrient medium (LNM) light-grown eer2 seedlings showed a significant hypocotyl elongation in response to low levels of 1-amino-cyclopropane-1-carboxylate (ACC), the precursor of ethylene, compared with the wild type, indicating that eer2 is hypersensitive to ethylene. Treatment with 1-MCP (1-methylcyclopropene), a competitive inhibitor of ethylene signalling, suppressed this hypersensitive response, demonstrating that it is a bona fide ethylene effect. By contrast, roots of eer2 were less sensitive than the wild type to low concentrations of ACC. The ethylene levels in eer2 did not differ from the wild type, indicating that ethylene overproduction is not the primary cause of the eer2 phenotype. In addition to its enhanced ethylene response of hypocotyls, eer2 is also affected in the pattern of senescence and its phenotype depends on the nutritional status of the growth medium. Furthermore, linkage analysis of eer2 suggests that this mutant defines a new locus in ethylene signalling

Adherence to HAART:processes explaining adherence behavior in acceptors and non-acceptors

In order to explore and clarify the underlying processes which lead to (non)-adherence behavior in patients treated with highly active antiretroviral therapy (HAART), a qualitative study was conducted. Thirty-seven in-depth interviews were held with 30 Caucasian HIV-positive patients. Additional data were collected by diaries kept by some participants. The analysis took place in a cyclic process; selection of themes was alternated with input of new material. Adherence to HAART is mainly influenced by the experience of being HIV positive. Acceptance or non-acceptance of HIV leads to one of two basic stances toward adherence: being determined to be adherent or medication is subordinate to other priorities in life. This stance determines the commitment to therapy and influences how patients cope with adherence. Patients who are determined to be adherent find solutions to adherence problems. Patients who are not determined to be adherent solve problems only if the solution does not compromise important aspects of their lives. Insight is provided into the manner in which prevalent themes; start of HAART, attitude toward medication, HAART in daily life, contextual factors, health and HAART and being informed, influence adherence behavior. Before starting HAART the focus should be on helping the patient to accept HIV as a part of life. The findings need to be taken into account in adherence-promoting interventions