17 research outputs found
Improvement of pain experience and changes in heart rate variability through music-imaginative pain treatment
Music-imaginative Pain Treatment (MIPT) is a form of music therapy addressing pain experience and affective attitudes toward pain. It includes two self-composed music pieces: one dedicated to the pain experience (pain music, PM) and the other to healing imagination (healing music, HM). Our non-experimental study addresses patients with chronic somatoform pain disorders participating in MIPT. The goal is to gain insight into the direct effect mechanisms of MIPT by combining outcome measures on both the objective physiological and subjective perception levels. The research questions are directed toward changes in pain experience and heart rate variability and their correlations. Thirty-seven hospitalized patients with chronic or somatoform pain disorders receiving MIPT participated in this study. Demographic data and psychometric measures (Symptom Check List SCL90, Childhood Trauma Questionnaire CTQ) were collected to characterize the sample. Subjective pain experience was measured by McGill Pain Questionnaire (SF-MPQ), and Heart Rate Variability by 24 h-ECG. Data analysis shows a reduction of reported pain from MT1 = 19.1 (SD = 7.3) to MT2 = 10.6 (SD = 8.0) in all dimensions of the SF-MPQ. HRV analyses shows a reduced absolute power during PM and HM, while a relative shift in the autonomic system toward higher vagal activity appears during HM. Significant correlations between HRV and MPQ could not be calculated. Findings are interpreted as a physiological correlate to the psychological processes of the patients. Future studies with more participants, a control-group design, and the integration of medium- and long-term effects are recommended
Characterization of Cytokinin and Adenine Transport in Arabidopsis Cell Cultures1[OA]
Cytokinins are distributed through the vascular system and trigger responses of target cells via receptor-mediated signal transduction. Perception and transduction of the signal can occur at the plasma membrane or in the cytosol. The signal is terminated by the action of extra- or intracellular cytokinin oxidases. While radiotracer studies have been used to study transport and metabolism of cytokinins in plants, little is known about the kinetic properties of cytokinin transport. To provide a reference dataset, radiolabeled trans-zeatin (tZ) was used for uptake studies in Arabidopsis (Arabidopsis thaliana) cell culture. Uptake kinetics of tZ are multiphasic, indicating the presence of both low- and high-affinity transport systems. The protonophore carbonyl cyanide m-chlorophenylhydrazone is an effective inhibitor of cytokinin uptake, consistent with H+-mediated uptake. Other physiological cytokinins, such as isopentenyl adenine and benzylaminopurine, are effective competitors of tZ uptake, whereas allantoin has no inhibitory effect. Adenine competes for zeatin uptake, indicating that the degradation product of cytokinin oxidases is transported by the same systems. Comparison of adenine and tZ uptake in Arabidopsis seedlings reveals similar uptake kinetics. Kinetic properties, as well as substrate specificity determined in cell cultures, are compatible with the hypothesis that members of the plant-specific purine permease family play a role in adenine transport for scavenging extracellular adenine and may, in addition, be involved in low-affinity cytokinin uptake
Overexpression of GLUTAMINE DUMPER1 leads to hypersecretion of glutamine from Hydathodes of Arabidopsis leaves.
Secretion is a fundamental process providing plants with the means for disposal of solutes, improvement of nutrient acquisition, and attraction of other organisms. Specific secretory organs, such as nectaries, hydathodes, and trichomes, use a combination of secretory and retrieval mechanisms, which are poorly understood at present. To study the mechanisms involved, an Arabidopsis thaliana activation tagged mutant, glutamine dumper1 (gdu1), was identified that accumulates salt crystals at the hydathodes. Chemical analysis demonstrated that, in contrast with the amino acid mixture normally present in guttation droplets, the crystals mainly contain Gln. GDU1 was cloned and found to encode a novel 17-kD protein containing a single putative transmembrane span. GDU1 is expressed in the vascular tissues and in hydathodes. Gln content is specifically increased in xylem sap and leaf apoplasm, whereas the content of several amino acids is increased in leaves and phloem sap. Selective secretion of Gln by the leaves may be explained by an enhanced release of this amino acid from cells. GDU1 study may help to shed light on the secretory mechanisms for amino acids in plants