W. Albert

Young patients who undergo heart transplantation in their early childhood or adolescence are confronted with typical developmental problems, which affect their specific adjustment to heart transplantation. This study aims at evaluating patients' health related quality of life and at determining the degree and sources of non-compliant behavior with its somatic and psychosocial consequences. The study sample consists of 38 patients, who received heart transplantation between the age of 1 and 18 and are now between 16 and 34 years old. All participants received self-rating instruments: The Short-Form Health Survey (SF-36), Giessen Subjective Complaints List (GBB), Medication Experience Scale for Immunosuppressants (MESI), and Health Questionnaire for Children and Young People (KIDSCREEN-27). Patient´s scores were compared to the scores of the specific norm sample. Further assessment was done by semi-structured interviews directed at psychosocial outcome, compliance, relationship to...

An assay of adenosine(5')tetraphospho(5')adenosine (Ap4A), based on the luciferin/luciferase method for ATP measurement, was developed, which allows one to determine picomolar amounts of unlabeled Ap4A in cellular extracts. In eukaryotic cells this method yielded levels of Ap4A varying from 0.01 microM to 13 microM depending on the growth, cell cycle, transformation, and differentiation state of cells. After mitogenic stimulation of G1-arrested mouse 3T3 and baby hamster kidney fibroblasts the Ap4A pools gradually increased 1000-fold during progression through the G1 phase reaching maximum Ap4A concentrations of about 10 microM in the S phase. Quiescent 3T3 cells reach a high level of Ap4A (1 microM) in a 'committed' but prereplicative state if exposed to an external mitogenic stimulant (excess of serum) and simultaneously to a synchronizer which inhibits entry into the S phase (hydroxyurea). When the block for DNA replication was removed at varying times after removal of the stimulant decay of commitment to DNA synthesis was found correlated with a shrinkage of the Ap4A pool. Cells lacking a defined G1 phase (V79 lung fibroblasts, Physarum) possess a constitutively high base level of Ap4A (about 0.3 microM) even during mitosis. From this high level, Ap4A concentration increases only about tenfold during the S phase. Temperature-down-shift experiments, using chick embryo cells infected with transformation-defective temperature-sensitive viral mutants(td-ts), have shown that the expression of the transformed state at 35 degrees C is accompanied by a tenfold increase of the cellular Ap4A pool. Treatment of exponentially growing human cells with interferon leads, concomitantly with an inhibition of DNA syntheses, to a tenfold decrease in intracellular Ap4A levels within 20 h. The possibility of Ap4A being a 'second messenger' of cell cycle and proliferation control is discussed in the light of these results and those reported previously demonstrating that Ap4A is a ligand of mammalian DNA polymerase alpha, triggers DNA replication in quiescent mammalian cells and is active in priming DNA synthesis.

Using a technique developed recently to detect DNA polymerase activity in situ after NaDodSO4 gel electrophoresis (Spanos, A., Sedgwick, S. G., Yarranton, g. T., Hübscher, U. & Banks, G. R. (1981) Nucleic Acids Res. 9, 1825-1839), we present evidence that a high Mr (greater than or equal to 125,000) polypeptide is responsible for chromosomal DNA replication in prokaryotes, lower eukaryotes and high eukaryotes. Not only extracts from Escherichia coli, Ustilago maydis, Drosophila melanogaster, rat neurones, calf thymus, human fibroblast, and HeLa cells possess such high Mr activities, but also highly purified E. coli DNA polymerase III core enzyme, U. maydis DNA polymerase, and D. melanogaster embryo and calf thymus DNA alpha polymerases. The evidence that these activities are responsible for chromosomal DNA replication is genetical (E. coli, U. maydis, and D. melanogaster); also, the high Mr activity disappears from rat neurones during differentiation from an actively dividing precursor cell to a postmitotically mature neurone. Furthermore, when limited proteolysis is allowed to occur, a defined and remarkably similar pattern of intermediate Mr activities is generated in lower eukaryotic and high eukaryotic extracts and, to some extent, in prokaryotic extracts. In higher eukaryotic extracts, a low Mr activity of approximately 35,000 is also generated. Protease inhibitors can retard formation of these catalytically active proteolytic fragments. We propose that the replicative DNA polymerase complex of both prokaryotes and eukaryotes contains a high Mr polypeptide responsible for chain elongation which might be conserved during evolution and which is extremely sensitive to proteolytic cleavage.

A panel of 12 hybridoma cell lines secreting monoclonal antibodies against alpha-polymerase were prepared by fusion of mouse myeloma cells and spleen cells of a rat immunized with homogeneous calf thymus alpha-polymerase. Hybridomas were selected and cloned on the basis of immunobinding to pure alpha-polymerase in solid phase radioimmunoassay. Antibodies secreted by these cells eventually were purified in milligram quantities from ascites fluids. These antibodies, all of the rat immunoglobulin M class, cross-reacted with alpha-polymerases from calf and monkey cells as revealed by immunobinding in radioimmunoassay and by immunoprecipitation of DNA polymerase activity. The antibodies were not capable of neutralizing the enzyme activity. With the methods described these antibodies may be used to immunoprecipitate alpha-polymerase from crude extracts of mammalian cells and to measure levels of the enzyme protein.

The goal of the current investigation was to propose and evaluate a method for estimating cumulative spinal loading based on the hypothesis that cumulative loading for a single task will be linearly proportional to its cycle time. The association between cumulative spinal ...