A Mathematical Submodel for the Planktonic Rotatoria in the Ecosystem of the Barther Bodden (Southern Baltic Sea)

Of the rotifers inhabiting the shallow eutrophic Barther Bodden, the pelagic species feeding on fresh detritus comprising dead diatoms and green algae are of particular importance in terms of biological production. The submodel presented here refers only to this functional group (Filinia longiseta, Brachionus quadridentatus and Keratella cochlearis). The biological situation, the working hypotheses, the equation system, the measured values and coefficients used and the wiring diagram are given. The curves obtained with the model are shown in detail and tested against various criteria. Agreement between the model curves and the measured data is good.     

Probability landscapes for integrative genomics

Background  

The comprehension of the gene regulatory code in eukaryotes is one of the major challenges of systems biology, and is a requirement for the development of novel therapeutic strategies for multifactorial diseases. Its bi-fold degeneration precludes brute force and statistical approaches based on the genomic sequence alone. Rather, recursive integration of systematic, whole-genome experimental data with advanced statistical regulatory sequence predictions needs to be developed. Such experimental approaches as well as the prediction tools are only starting to become available and increasing numbers of genome sequences and empirical sequence annotations are under continual discovery-driven change. Furthermore, given the complexity of the question, a decade(s) long multi-laboratory effort needs to be envisioned. These constraints need to be considered in the creation of a framework that can pave a road to successful comprehension of the gene regulatory code.     

Suspension cultures of human malignant lymphoma in the leukocyte migration test

The effects of supernatants of primary and secondary malignant human lymphoma cell cultures were analyzed as parameters of spontaneous secretion of factors by these cells using the leukocyte migration test (LMT). Spontaneous cultivation for up to five weeks was successful in four cases. The postulated production of mediators, i.e. the inhibitory and stimulating effects on leukocyte migration were characterized by testing the influence of (a) concentration, (b) temperature and (c) absorption with normal blood leukocytes on the effect. Reproducible stimulatory and inhibitory effects on the migration of normal leukocytes were dependent on concentration and temperature and were apparently mediated by one or more factors. The supernatants of a lymphoblastic lymphosarcoma of the T-cell type and of a lymphoblastic lymphosarcoma clearly revealed congruous and reproducible inhibitory effects. A further case of lymphoblastic lymphosarcoma that could not exactly be defined with immunological methods either and a case of centroblastic/centrocytic lymphosarcoma exhibited stimulating effects which could be reduced in a time-dependent manner through preincubation with blood leukocytes. The results of these studies support the assumption that malignant lymphoma cells are capable not only of secreting immunoglobulin, but also of other biologically effective secretion. The effects of such secretion are differentiated into stimulating and inhibitory ones. They might be important for the spreading of a tumor or for resistance of the organism to the disease.     

The synthesis of prostaglandin analogs containing hydroxycyclohexenyl rings.

The synthesis of prostaglandin analogs incorporating the 3-hydroxycyclohexenyl moiety in place of the natural C13-C20 side-chain has been accomplished via copper-assisted conjugate addition of the cycloalkenyllithium 2 to the cyclopentenous intermediates 4, 7 and 10.