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Biomedical subjects

D Nachbaur

Publications and source records attributed to D Nachbaur.

46 records · Page 3Linked to original sources
PubMed1993

Cytokine serum levels during treatment with high-dose recombinant human IL-3 in a patient with severe aplastic anemia.

A 37-year-old woman with severe aplastic anemia (SAA), who had relapsed 6 years after antilymphocyte globulin therapy, was treated with intravenous recombinant human IL-3 (4 micrograms/kg/d) for 21 days. Subsequently, long-term therapy with subcutaneous rhIL-3 at the highest dose level tested so far (16 micrograms/kg/d) was initiated in order to maintain growth-factor response. Therapy was discontinued on day 73 due to progressive thrombocytopenia and increased petechial bleeding. Both treatment schedules resulted in a transient increase in leukocytes (twofold) due to an increase in monocytes, neutrophils, and eosinophils. RhIL-3 had no effect on hemoglobin values or platelet counts and only marginally improved colony formation of bone marrow CFU-GM in response to rhGM-CSF. Side effects of both treatment schedules were mild and did not exceed WHO grade II. Steady-state serum concentrations of IL-3, which are able to stimulate hematopoiesis in vitro (i.e. > 1 ng/ml), were achieved by both low- and high-dose treatment, although high-dose treatment resulted in markedly higher serum levels of IL-3. On measuring cytokine serum levels (neopterin, IL-1 beta, IL-6, sIL-2R, GM-CSF, TNF-alpha, IFN-gamma) we noticed a different cytokine pattern with both treatment modalities, resulting in a moderate induction of TNF-alpha and IFN-gamma during low-dose, intravenous treatment, whereas during subcutaneous, high-dose treatment a profound increase of IL-6, sIL-2R, and, to a lesser extent, neopterin was detected. These results in a single patient with SAA indicate that further studies on IL-3 serum levels and IL-3-induced secondary cytokines in a larger group of patients are needed to optimize growth-factor treatment and to better understand the in vivo biological activity of IL-3.

Adult↗
PubMed1991

Phenotype and topography of human thymic B cells. An immunohistologic study.

Using single and double labeling immunohistochemical techniques and a large panel of monoclonal antibodies against B-cell differentiation antigens, including those newly defined at the Fourth International Leucocyte Typing Workshop, we have examined the immunophenotype and tissue distribution of human thymic B-cells. The existence of a distinct B-cell population as a constant constituent of the thymic microenvironment has been noted only recently. We found a significant population of B-lymphocytes in the thymic medulla expressing the B-cell restricted antigens CD19, CD20, CD22, CD37, CD72, CD76 and IgM and IgD. As with other extrafollicular B-lymphocytes, they differ significantly from both follicle mantle and germinal center cells in morphology and immunophenotype, which points to alternative modes of B-cell differentiation. Thymic B-cells themselves show considerable heterogeneity and a subpopulation with dendritic features and the expression of CD23 has been referred to as "asteroid" cells. Their close association with T-cells and medullary epithelial cells points to a functional role for B-cells in the thymus. A second population of B-lymphocytes together with frequent lymph follicles is found within the extrathymic perviascular space. Though separated from the medulla by a layer of epithelial cells, a clear distinction between the B-cells of these two compartments is not always possible. The intramedullary B-cell compartment shows a parallel numeric increase with the occurrence of germinal centers in the perivascular space, mostly due to an accumulation of B-cells in the medulla adjacent to these lymph follicles. Thus a close relationship between the intra- and extramedullary B-cell population of the thymus seems likely.

Adolescent↗
PubMed1991

Interferon alfa-2b with VMCP compared to VMCP alone for induction and interferon alfa-2b compared to controls for remission maintenance in multiple myeloma: interim results.

The present trial was designed to evaluate whether interferon (IFN) combined with standard induction chemotherapy and/or interferon remission maintenance treatment improve treatment results in patients with multiple myeloma. Up to now 89 patients have received IFN plus vincristine/melphalan/cyclophosphamide/prednisolone (VMCP) as induction therapy, and 86 conventional VMCP. The proportion of patients with progressive disease was significantly lower (P less than 0.005) under IFN + VMCP as compared to the VMCP treatment group. Survival times were significantly longer (P less than 0.02) after IFN + VMCP induction therapy than after VMCP alone. In the second phase of this investigation, 33 progression-free myeloma patients were assigned to receive IFN as maintenance therapy, and 41 patients served as untreated controls. Patients maintained with IFN showed a tendency towards increased progression-free survival. Haematological side effects were observed significantly more often in patients receiving IFN, with more severe haematological toxicity in patients on the combined IFN + VMCP regimen and an increased number of patients with mild haematological toxicity in the group maintained with IFN. Other side effects, such as fever and fatigue, remained within tolerable limits. In conclusion, the preliminary results of this current clinical trial indicate significant advantages of combined IFN + VMCP induction treatment in terms of reduced disease progression and prolonged survival and possible benefits of IFN maintenance therapy in patients with multiple myeloma.

Adult↗
PubMed1991

Thymic B cells.

Explore the source record for details and available documents.

B-Lymphocytes↗
PubMed1991

Bone marrow diagnosis in lymphoproliferative disorders: comparison of results obtained from conventional histomorphology and immunohistology.

In this study we have investigated 313 bone marrow biopsies from 280 patients with lymphoproliferative disorders. Trephines were sectioned transversely to obtain one cylinder for cryostat sectioning and immunostaining and a second for histomorphological evaluation using a plastic-embedding technique. The results obtained by histomorphological and immunohistological evaluation were compared for their contribution to staging and classification. Using both techniques, bone marrow involvement was seen in 3/43 (7.0%) biopsies from patients with Hodgkin's disease and in 193/270 (71.5%) cases with non-Hodgkin's lymphoma, including multiple myeloma and acute lymphocytic leukaemia. Immunohistology proved superior in detecting minimal mainly interstitial bone marrow infiltration in 15 leukaemia/lymphoma cases. Biopsies showing infiltration with both methods (n = 157) were re-examined for classification of lymphomatous infiltrates. Whereas immunohistology did not provide additional information in cases with Hodgkin's disease and myeloma, this method was crucial for establishing the definitive diagnosis in a number of cases with acute lymphocytic leukaemia and non-Hodgkin's lymphoma. In all of six leukaemia cases, in which no or inadequate material was available for immunophenotyping of cell suspensions, immunohistology clearly defined the subtype. In the 140 cases of non-Hodgkin's lymphoma the majority of cases (76.4%) were identically classified. In some cases, with important prognostic and therapeutic implications, immunohistology alone provided the definitive diagnosis: T-cell lymphoma (n = 2), hairy cell leukaemia (n = 2) and centrocytic non-Hodgkin's lymphoma (n = 3). Bone marrow immunohistology is, therefore, an important supplement for classical lymphoma/leukaemia diagnosis. The differences observed between histomorphology and immunohistology emphasize the importance of lymph node biopsy in lymphoma classification.

Biomarkers↗
PubMed1990

Stimulation of colony formation of various human carcinoma cell lines by rhGM-CSF and rhIL-3.

We studied the effects human recombinant granulocyte-macrophage colony-stimulating factor and human recombinant interleukin-3 on the colony formation of three human solid tumor cell lines. Using a modified double-layer soft agar clonogenic assay rhGM-CSF enhanced colony formation of all cell lines tested in a dose dependent manner (up to twofold for the breast cancer cell line BT-20, up to 163% of the control for the hypernephroma cell line C 94 and up to 147% for the non-small cell lung cancer cell line CCL 185 at a concentration of 100 ng/ml). RhIL-3 stimulated colony formation of the cell lines C 94 and BT-20, whereas on the cell line CCL 185 rhIL-3 had no effect even at the highest dose level tested (100 ng/ml). Combinations of growth factors showed subadditive stimulation on two cell lines tested (BT-20, C 94). These data indicate that haematopoietic growth factors exert a growth promoting activity on certain solid tumor cells in vitro at physiological concentrations. Therefore our results suggest that the application of these factors in immuno- and myelosuppressed cancer patients after high dose chemotherapy should be seen in light of a possible co-stimulation of the malignant cells.

Agar↗
PubMed1990

Value of urinary neopterin in the differential diagnosis of bacterial and viral infections.

Neopterin is released by stimulated macrophages. In this study we analyzed the diagnostic potential of urinary neopterin concentrations in patients with bacterial and viral infection. All but one of 17 patients with viral infection had increased urinary neopterin concentrations. Patients with bacterial urinary tract infection also showed increased neopterin concentrations, whereas patients with bacterial pneumonia had significantly lower neopterin levels. In addition, patients with acute bacterial pneumonia had lower neopterin levels than patients with protracted infection. A significant inverse correlation between urinary neopterin and hemoglobin concentrations was found. Neopterin concentrations could serve as a helpful additional marker of infectious diseases. Combined with other clinical and laboratory parameters it is a useful parameter for distinguishing between viral and bacterial origins of infection, as was shown by multivariate stepwise linear discriminant analysis.

Adult↗
PubMed1990

Correlation between neopterin, interferon-gamma and haemoglobin in patients with haematological disorders.

In this study, we further investigated a possible link between activation of cell-mediated immunity and anaemia in patients with haematological neoplasias. We compared serum concentrations of interferon-gamma and neopterin with haemoglobin levels. Significantly increased interferon-gamma and neopterin concentrations indicated persistent activation of cell-mediated immunity. Neopterin levels correlated significantly to interferon-gamma concentrations and inversely to haemoglobin levels. The data indicate an association between activated macrophages and the development of anaemia in patients with haematological neoplasias.

Adult↗
PubMedDate not supplied

Time after bone marrow transplantation as an important variable for quality of life: results of a cross-sectional investigation using two different instruments for quality-of-life assessment.

Quality of life (QoL) was investigated in 56 BMT recipients. The objective was to compare QoL in terms of physical, emotional, and social functioning between patients within the first year after BMT (n = 15) and patients who were alive more than 1 year after BMT (n=41). The Functional Assessment of Cancer Therapy Scale (FACT-BMT) and the EORTC-Quality of Life Questionnaire (EORTC-QLQ C30) were used to evaluate QoL as perceived by the patients. Results show a significantly reduced general QoL in patients within the first year after BMT. Specific differences were identified on the dimensions of physical and emotional well-being and the symptom scales of appetite loss, fatigue, pain, dyspnea, and nausea and vomiting. QoL improves significantly with time after BMT. We suggest that there should be more integration of QoL expectancy into the pre-BMT information process. Patients should be informed about potential deficits in physical and emotional well-being within the first year after BMT. This could enhance insight and compliance in the critical period early after BMT.

Adult↗