Search PubMed⌕ Search

Biomedical subjects

Sonja Fischer

Publications and source records attributed to Sonja Fischer.

5 recordsLinked to original sources

Coordination-driven self-assemblies with a carborane backbone.

The design and self-assembly of five new supramolecular complexes (a rectangle, a triangle, a hexagon, and two squares) are described. These assemblies incorporate carborane building blocks and were prepared in excellent yields (>85%). The assemblies and building blocks were characterized with multinuclear NMR spectroscopy, electrospray ionization mass spectrometry, and elemental analysis. Isotopically resolved mass spectrometry data confirm the existence of the rectangle, triangle, and hexagon, and NMR data are consistent with the formation of all five assemblies. The X-ray structures of two linear carborane building blocks, 1,12-(4-CC(C(5)H(4)N)(2)-p-C(2)B(10)H(10) (1) and 1,12-(trans-(Pt(PEt(3))(2)I)CC)(2)-p-C(2)B(10)H(10) (2), are reported: 1 is monoclinic, P2(1)/c, a = 10.6791(4) A, b = 8.0091(14) A, c = 11.6796(4) A, beta = 107.8461(15) degrees , V = 950.89(5) A(3), Z = 2; 2 is monoclinic, C2/c, a = 62.1128(10) A, b = 22.0071(3) A, c = 14.0494(2) A, beta = 89.9411(8) degrees , V = 19204.4(5) A(3), Z = 16. Crystals of the linear linker 1 exhibit close pi-pi pyridine and pyridine-B(carborane) interactions, which are discussed.

Boranes↗

Awareness of activity limitations and prediction of performance in patients with brain injuries and orthopedic disorders.

The aim of this study was to compare the accuracy of performance predictions in experimental tasks with patients' awareness of activity limitations. Participants were 24 patients with brain injuries (i.e., traumatic brain injury and cerebrovascular disorders) and 22 patients with orthopedic disorders. Prediction of performance was examined in a memory task (word list learning) and a motor task (finger tapping). Awareness of activity limitations was measured by comparing patients' self-ratings and staff ratings in the Patient Competency Rating Scale (PCRS). Results for the PCRS showed that patients with orthopedic disorders underestimated and patients with brain injuries (i.e., patients with TBI) overestimated their level of functioning in the total scale and the social/emotional subscale in comparison to staff ratings. Both patient groups agreed with staff ratings in physical/basic self-care items. In the predicted performance tasks a similar pattern could be observed: None of the groups showed an overestimation of performance in the motor task, whereas patients with brain injuries overestimated their competency in the memory task. However, the agreement between both awareness measures (PCRS, predicted performance) was only low, which indicates that they might measure different aspects or levels of self-awareness.

Awareness↗

Awareness of activity limitations, goal setting and rehabilitation outcome in patients with brain injuries.

PRIMARY OBJECTIVE: To examine the relationship between self-awareness, goal setting ability (i.e. ability to set realistic goals) and performance/outcome in a cognitive task and for rehabilitation. RESEARCH DESIGN: Regression analyses were conducted to compare the predictive power of self-awareness and demographic/neuropsychological variables on goal setting ability and performance/outcome. METHODS AND PROCEDURES: Self-awareness of 63 patients with brain injuries was measured by direct clinicians' rating and the difference between patient and staff ratings in a questionnaire. RESULTS: The awareness measures predicted 32% of the variance for goal setting ability in the rehabilitation context but only 4% of the goal setting variance in the cognitive task. Similarly, self-awareness predicted 33% of the variance for rehabilitation outcome but only 5% of the performance in the cognitive task. CONCLUSIONS: Self-awareness seems to be related to goal setting ability and outcome in a long-term rehabilitation process but less in short-term experimental tasks.

Adult↗

Synergism between lectins and vesicles of Viscum album L.- detection by biochemical and immunological methods.

Mistletoe (Viscum album L.) extracts, used in cancer therapy, contain several antitumor and immunologically active ingredients of which the cytotoxic mistletoe lectins and the immunoactive vesicles of chloroplast membranes are particularly important. We have investigated interactions between vesicles and lectins with respect to the question of synergistic or antagonistic effects. First we used biochemical methods. Lectin binding to vesicles was dependent on the pH-value and ionic strength of the buffers used. The strongest interaction was observed at low pH-values and at low ionic strength. Using immunological methods, we found that the combination of lectins and vesicles showed a strong amplifying synergistic effect on the stimulation of lymphocyte proliferation. We found an antagonistic effect in terms of cytotoxicity. In summary, these results demonstrate a significant influence of vesicles on all commonly used methods of determination of mistletoe lectins.

Journal Article↗