Biomedical subjects

A Büssing

Publications and source records attributed to A Büssing.

62 records · Page 4Linked to original sources

PubMedDate not supplied

Release of interleukin-6 in cultured B-chronic lymphocytic leukaemia cells is associated with both activation and cell death via apoptosis.

BACKGROUND: There is growing evidence that some cytokines promote B cell survival, while others enhance cell death. Interleukin-6 was reported to induce proliferation of chronic lymphocytic leukaemia (B-CLL) cells, and to enhance survival of these cells through inhibition of spontaneous apoptosis. MATERIALS AND METHODS: To more clearly define the effects of an in vitro stimulation of B-CLL cells, lymphocytes from 13 patients with B-CLL and from 6 healthy individuals were incubated for 7 d with immunomodulators such as interleukin-6 (IL-6), pokeweed mitogen (PWM), lipopolysaccharides (LPS), and extracts from Viscum album L. (VAL; Helixor), which were recognised to induce apoptosis but also to induce a release of pro-inflammatory cytokines such as IL-1, IL-6, and tumour necrosis factor-alpha. RESULTS: Although both, IL-6 and PWM induced a release of IL-6 and expression of the activation markers CD25 and CD71 on the surface of B-CLL cells, IL-6 did not increase or accelerate the proliferation of these cells. In contrast, VAL extracts did not result in an upregulation of activation markers or proliferation of B-CLL cells but induced both, cell death via apoptosis and IL-6 release. In response to PWM, only few clones of leukemic B cells incorporated the thymidine-analogue 5-bromo-2'-deoxyuridine. Moreover, a remarkable response of B-CLL cells towards the immunomodulators was observed only in one patient with an advanced stage. CONCLUSIONS: These preliminary results do not support theoretical objections of a B-CLL stimulation via induction of IL-6 in vitro.

Aged↗

PubMedDate not supplied

Differential binding of toxic lectins from Viscum album L., ML I and ML III, to human lymphocytes.

The killing capacity of extracts from Viscum album L., widely used as an adjuvant in complementary cancer therapy, is dependent on the content of toxic proteins, especially the mistletoe lectins (ML). Although one may expect a homogeneous distribution of 'receptors' for these proteins on the cell surface, the sensitivity of cells to the ML-mediated cytotoxicity obviously differs, as the galNAc-binding ML III in contrast to the gal-binding ML I selectively killed CD8+ lymphocytes with a 'memory' phenotype (CD62Llo), while CD19+ B cells remained almost unaffected. B cells hardly bind ML III but did bind the gal-specific ML I. In accordance with these observations, in leukaemic B cells from patients with B chronic lymphocytic leukaemia and the human IgE-secreting myeloma cell line U-266 a strong induction of apoptosis-associated mitochondrial Apo2.7 molecules was observed after treatment with ML I and less effectively by ML III, while in the leukaemic T cell line Molt-4 both ML were strong inductors of apoptosis. In the light of these findings, the possible impact of ML I- and ML III-rich mistletoe extracts in the treatment of B cell neoplasia has to be carefully investigated.

Apoptosis↗

PubMedDate not supplied

Toxic proteins from European mistletoe (Viscum album L.): increase of intracellular IL-4 but decrease of IFN-gamma in apoptotic cells.

BACKGROUND: Mistletoe lectins (ML), the major biologically active components of mistletoe extracts, which are used for adjuvant cancer therapy, induce apoptosis in lymphocytes and tumor cells. In addition, ML at toxic concentrations induce the release of cytokines, but it remains unclear as to whether dying or activated cells are responsible. MATERIALS AND METHODS: By flow cytometry, expression of IFN-gamma, IL-4, apoptosis marker Apo2.7 and anti-apoptotic Bcl-2 proteins were analyzed in response to ML or viscotoxins (VT) in PBMC from controls and plasmocytoma cells (U-266). RESULTS: While ML inhibited PMA/Ca-ionophore/monensin co-stimulated IFN-gamma production, they increased IL-4 expression in CD8+ and CD4+ T-cells. Thereby, IL-4 was mainly expressed in apoptotic cells with a low level of Bcl-2 proteins. In contrast, the cell membrane permeabilising VT induced complete loss of Bcl-2 proteins but did not stimulate IL-4 production within 24 hours, indicating that IL-4 expression is related to apoptosis but not to necrosis. CONCLUSION: Despite the role of IL-4 during activation of type2 T-helper cells, IL-4 expression may play an important yet undefined role during apoptosis of normal and tumor cells.

Apoptosis↗

PubMedDate not supplied

Intracellular expression of IL-4 and inhibition of IFN-gamma by extracts from European mistletoe is related to induction of apoptosis.

BACKGROUND: Extracts from European mistletoe are used for adjuvant cancer treatment. Their influence on the intracellular expression of cytokines of the T-helper cells type-1 (Th1; IFN-gamma) or type-2 (Th2; IL-4) is still unknown. MATERIALS AND METHODS: Lymphocytes from controls were incubated with mistletoe extracts (ME) and mistletoe lectins (ML) for 24 hours and co-stimulated with PMA/Ca-ionophore/monensin during the last 6 hours. Apoptosis and intracellular cytokine expression were detected by flow cytometry, the cytokine release into the supernatants by ELISA. RESULTS: ME and ML significantly inhibited intracellular expression of IFN-gamma but stimulated IL-4. Thereby, IL-4 was mainly expressed in apoptotic (Apo2.7+) cells. However, IFN-gamma secretion into the supernatants of the cells was dose-dependently inhibited by ME and ML, while IL-4 was not detected at all. CONCLUSION: The intracellular expression of the 'Th2-cytokine' IL-4 in ME- and ML-exposed cells may not be related to a typical Th2-response but rather to cell death. This effect might be of great relevance e.g. after intratumoural injection of the mistletoe extracts and, in general, for the inhibition of an inflammatory response during apoptosis.

Apoptosis↗

PubMedDate not supplied

Recent developments of care information systems in Germany.

The authors describe recent developments in the German health care system. A taking stock of the current state of hospital information system implementations in Germany leads to the conclusion that up to now no integrated hospital information system can be found, but that the awareness for the necessity of such a system is growing. Anticipated challenges and risks of care information systems are examined on grounds of an exemplification by the German care information system PIK (Pflegedienst im Krankenhaus--Nursing service in hospital). With regard to the shift from functional to holistic nursing in Germany it is argued that the consequences of the implementation of a care information system are intertwined closely with the nursing model.

Computer Communication Networks↗

PubMedDate not supplied

The challenges of a care information system reflecting holistic nursing care.

In this article two recent developments in the German health care system are outlined. On one side, an increasing economic pressure and legal changes on the German health care system lead to growing computerization in German hospitals. On the other side, a shift from functional to holistic nursing is observed. The question is raised if within the paradigm of holistic nursing computer support is an adequate way to organize and design work. The newly developed German care information system, PIK (Pflegedienst im Krankenhaus--Nursing service in hospital), serves as an example for a program that is structured according to the nursing process. On the grounds of this exemplification it is argued that within the concept of "technology as an option" not only is the design of a program important but also its basic work organization and design. The authors come to the conclusion that computer support of holistic nursing is possible. However, it is shown that some aspects of nursing (for example, intuitive knowledge, which has been identified as an integral part of expert nursing) cannot be formalized and thus cannot be supported by computer systems.

Germany↗

PubMedDate not supplied

Mistletoe in immunology and the clinic (short review).

The recent meeting of the AGMIF (Working Group for Mistletoe Therapy and Immunological Research) held in Herdecke, Germany, on October, 3rd, 1997, covered recent developments in the field of immunological and biological properties of Viscum album L., the European mistletoe, which is used for adjuvant cancer treatment. So far, one extract component, the mistletoe lectin (ML)-1, was propagated by some researchers to be the only relevant substance within the extracts. However, immunological activities of other extract components such as polysaccharides, vesicles, chitin-binding lectin and their interactions discussed in the first part, underline the significance of the other components as well. In the second part, clinical evidence for the beneficial effects of subcutaneous and intratumoral application of mistletoe therapy was presented by different working groups. However, further research is of great importance to carefully analyse and characterize the involved molecules and exact mechanisms underlying the beneficial effects reported in this meeting.

Animals↗

PubMedDate not supplied

Generation of reactive oxygen intermediates (ROI) by the thionins from Viscum album L.

BACKGROUND: Extracts from Viscum album L. are widely used as an adjuvant in complementary cancer therapy. While the mechanisms of mistletoe lectin (ML) cytotoxicity are well described, the viscotoxin (VT) effects are unclear at present. Thus, we treated human lymphocytes with VT and measured cell death-associated changes by flow cytometry. RESULTS: Treatment of lymphocytes with VT for 2 hours resulted in the binding of Annexin-V, permeabilisation of cell membranes, and generation of ROI. Apart from interindividual differences in response to VT, the number of intracellulary Bcl-2 proteins increased only marginally. The VT A1, A2, A3 and 1-PS were similar in their ROI-inducing potencies, while other cationic and/or amphipathic substances such protamine sulfate, VT B, purothionin or wasp venom peptides mastoparan I and II were less effective. However, the cytotoxic properties of VT-rich whole plant extracts from mistletoe grown on different host trees (Iscador), correlated with the content of ML rather than VT. CONCLUSIONS: Permeabilisation of lymphocytes cell membranes by VT was associated with generation of ROI within 2 hours indicating accidental cell death. VT cannot be ignored any longer as they posses both immunomodulating and cytotoxic properties, which both might be of clinical relevance.

Antimicrobial Cationic Peptides↗