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Biomedical subjects

M Schaadt

Publications and source records attributed to M Schaadt.

At least 19 recordsLinked to original sources
PubMed2000

Patients with fibromyalgia have normal serum levels of hyaluronic acid.

OBJECTIVE: To investigate the levels of hyaluronic acid (HA) in Danish patients with fibromyalgia (FM). METHODS: Serum levels of HA were determined in 53 patients with established FM and 55 control samples using a radiometric assay. Values were correlated to clinical disease severity variables (duration of disease, tender point scales, visual analog scales). RESULTS: There were no differences in HA levels between patients and controls. HA levels of all patients except one were within the reference ranges. There was no association between HA levels and clinical findings. CONCLUSION: Patients with FM do not generally have increased serum levels of HA.

Aging↗
PubMed1991

Expression of interleukin-6 and interleukin-6 receptor in Hodgkin's disease.

Interleukin-6 (IL-6) is a multipotent lymphokine that can mediate differentiation of B cells into Ig-secreting cells, stimulate the growth of plasmacytomas, hybridomas, and T cells, and induce acute-phase proteins in liver cells. It has been suggested that IL-6 is involved in the pathogenesis of several diseases by autocrine or paracrine pathways. To examine whether IL-6 is possibly involved in the pathophysiology of Hodgkin's disease (HD), we analyzed the expression of IL-6 and IL-6 receptor mRNA and protein in cell lines and primary specimens from patients with HD. IL-6-specific transcripts were detected in three of six HD-derived cell lines by Northern blot analysis. In the culture supernatants of four HD-derived cell lines, IL-6 was detected by radioimmunoassay. Biologic activity of IL-6 was confirmed by proliferation of an IL-6-dependent cell line. In situ hybridization experiments showed IL-6-specific transcripts in Hodgkin (H) and Reed-Sternberg (RS) cells in primary tissues of two patients. In addition, mRNAs specific for the IL-6 receptor were detected in five HD-derived cell lines. Immunostaining experiments showed expression of IL-6 receptor molecules on H and RS cells in 8 of 16 cases with HD. Thus, our data suggest that IL-6 might be involved in the pathophysiology of HD.

Antibodies, Monoclonal↗
PubMed1990

L428 cells derived from Hodgkin's disease produce E rosette-inhibiting factor.

Diminished rosetting capacity of T cells is a well-known phenomenon in Hodgkin's disease, and inhibitors of E rosette formation have been reported to be present in the plasma of patients with Hodgkin's disease. The cell line L428, representing an in vitro counterpart of Hodgkin and Sternberg-Reed cells, could be shown to release a factor capable of suppressing the binding of sheep red blood cells (SRBC) to normal peripheral-blood T lymphocytes or to a T-cell line (L735). At maximally effective concentrations, RIF (rosette inhibiting factor) inhibited T lymphocyte rosetting by approximately 40% (mean from 184 healthy controls). The diminished E rosetting of T lymphocytes from Hodgkin's patients was not further suppressed by added RIF. This factor inhibited binding of SRBC to their target cells at 37 degrees C but not at 4 degrees C. The factor could be stored lyophilized at -20 degrees C and was stable at 56 degrees C (30 minutes). RIF was inactive below pH 6 and above pH 9 or after trypsin digestion. Purification by affinity, ion exchange, and molecular sieve chromatography showed activity peaks at 12.5 Kd, 25 Kd, 50 Kd, and 100 Kd.

Cell Line↗
PubMed1990

Phase II study of recombinant human tumor necrosis factor in colorectal carcinoma.

Fifteen patients with colorectal carcinoma received a 30-min intravenous infusion of recombinant human tumor necrosis factor (rHuTNF) to investigate the value of rHuTNF in the treatment of colorectal carcinoma. Patients received 5 x 10(5) U/m2 (217 micrograms/m2) on day 1, and in the absence of serious side effects 10 x 10(5) U/m2 (435 micrograms/m2) on day 3 and 15 x 10(5) U/m2 (652 micrograms/m2) on day 5. The cycle was repeated on day 28. Full dose escalation was possible in all patients. There was a minor response in one patient (disappearance of retroperitoneal lymph nodes). All other patients showed progressive disease. At the dose and schedule used, rHuTNF had minimal therapeutic activity in colorectal carcinoma.

Adolescent↗
PubMed1990

Monitoring of tumor necrosis factor therapy with neopterin.

As neopterin is only secreted by stimulated macrophages, serum neopterin levels are an important marker for cellular immunity. Daily determinations of serum neopterin were performed in five patients with advanced colorectal carcinoma receiving a therapy with tumor necrosis factor (TNF). 24 h after every TNF infusion a significant, but only short-lasting increase of neopterin was observed. This effect was dependent on the applicated TNF dose. These results prove that determinations of serum neopterin levels are a helpful parameter for monitoring an immunomodulating therapy with TNF.

Biopterins↗
PubMed1989

Effects of recombinant tumor necrosis factor (rHuTNF alpha) on human neutrophils and monocytes: in vitro, ex vivo and in vivo.

In in vitro experiments, tumor necrosis factor (rHuTNF alpha) was found to inhibit spontaneous and directed migration of normal human neutrophils and monocytes. RHuTNF alpha showed no chemoattractant activity. In conjunction with a Phase-2 clinical trial, we also studied in vivo rHuTNF alpha effects on neutrophil and monocyte number and function. At the time of maximal plasma TNF levels (30 min), marked neutropenia and monocytopenia were observed. Isolated neutrophils were activated for superoxide production but were unable to migrate. Monocyte migration was inhibited at later times. Neutrophil migratory function recovered between 4 and 8 h but was again depressed at 24 h. The data demonstrate the complexity of the response to TNF, comprising direct and indirect effects which are concentration-, time- and place-dependent. They further suggest that the only neutrophils and monocytes available for participation in an anti-tumor activity of TNF in vivo are those present in the tumor at the outset.

Chemotaxis, Leukocyte↗
PubMed1989

[Mechanism of resistance to tumor necrosis factor].

To find clues as to the possible mechanisms of resistance against the cytotoxic activity of tumor necrosis factor (TNF), we developed TNF-resistant and TNF-sensitive subclones of the human cervic carcinoma cell line ME 180 and the mammary carcinoma cell line BT-20. Resistant subclones were selected by gradually increasing the TNF concentration in the culture medium over 4 months or 20 passages. Resistance to TNF was conserved in the absence of TNF after nearly 3 years and less than 100 passages. There were no differences in the number and affinity of TNF receptors between the sensitive and resistant clones. Similarly, SDS-PAGE of cell lysates showed identical bands. Sensitivity to actinomycin D, mitomycin C, and interferon-gamma was the same. No TNF message could be demonstrated in either subclone. As tumors grown in nude mice derived from the sensitive and resistant clones responded equally well to an intratumoral injection of TNF, we conclude that different mechanisms are responsible for sensitivity and resistance to the cytotoxic effect of TNF in vitro and in vivo.

Animals↗
PubMed1989

European experience with ifosfamide in lymphomas.

In malignant lymphomas, ifosfamide-containing regimens were at first used mainly in second-line therapy and response-adapted protocols. Currently, in combination with other drugs, ifosfamide is being used in several phase-III trials. As salvage therapy in non-Hodgkin's lymphoma (NHL), IMV-Bleo (ifosfamide, methotrexate, etoposide, bleomycin) produced a complete remission (CR) rate of 41% and seemed to be particularly effective in patients with suboptimal response to first-line treatment. IBEP (ifosfamide, bleomycin, etoposide, procarbazine), in combination with procarbazine and bleomycin was an effective non-cross-resistant alternative in CHOP (cyclophosphamide, hydroxydauomycin/doxorubicin, vincristine, prednisone)-refractory NHL. In a trial of response-oriented therapy in high-grade malignant lymphoma patients, the investigators concluded that consolidation therapy was necessary even in patients with rapid response to CHOP. Patients with NHL resistant to or relapsing from conventional chemotherapy or with MOPP-ABVD (mechlorethamine, vincristine, procarbazine, prednisone, doxorubicin, bleomycin, vinblastine, decarbazine)-resistant Hodgkin's disease (HD) were treated with BMV-VIP [bleomycin, plus high-dose methylprednisolone plus ifosfamide, etoposide, plus methylprednisolone]. In high-grade malignant NHL, patients received three cycles of COP-BLAM (cyclophosphamide, vincristine, procarbazine, prednisone, bleomycin, doxorubicin). Those who achieved CR received two more cycles of COP-BLAM and IMV (ifosfamide, methotrexate, etoposide) as consolidation therapy. Patients in partial remission (PR) or with less of a response to COP-BLAM were switched to IMV. After reaching CR, patients received two additional cycles as consolidation therapy. After the second restaging, patients were randomized to observation v additional radiotherapy. Of 191 patients, 148 have passed first restaging with 51% in CR; 85 went through the second restaging with 61% in CR. Of 32 patients who only reached PR after the first restaging, 15 (47%) achieved CR with IMV. For primary treatment of HD, the German Hodgkin Study Group added a third non-cross-resistant regimen, IMEP (ifosfamide, methotrexate, etoposide, prednisone), to supplement COPP (cyclophosphamide, vincristine, procarbazine, prednisone) and ABV in the primary treatment of HD. In a pilot study, 87% of 63 evaluable patients reached CR. The current phase-III protocol is comparing COPP/ABVD with fast alternating cycles of COPP/ABV/IMEP.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1988

Inhibition of human neutrophil migration by supernatants from Hodgkin's disease-derived cell lines.

The contribution of defective neutrophil function to the increased susceptibility to infection observed in patients with Hodgkin's disease is unclear. We describe cell-directed inhibition of normal human neutrophil migration by serum-free culture supernatants of the Hodgkin-derived cell line L428 KSA, tentatively termed Hodgkin-derived leucocyte factor (HDLF). This factor inhibits both random migration and migration toward different chemoattractants, appears to bind to the cell surface and is stable at 56 degrees C but destroyed at 100 degrees C. Hodgkin-derived leucocyte factor also stimulates basal neutrophil superoxide production but the cells remain fully responsive to n-formyl-methionylleucylphenylalanine. Gel filtration chromatography shows a single peak of migration-inhibitory and superoxide-stimulatory activity at approximately 70,000 g mol-1. Hodgkin-derived leucocyte factor migration inhibition persists in neutrophils from a patient with chronic granulomatous disease. Activity of HDLF is completely destroyed by trypsin but unaffected by the protease inhibitor phenyl-methylsulphonylfluoride. Hodgkin's factor appears to be different from previously described neutrophil migration inhibitory factors.

Cell Migration Inhibition↗
PubMed1988

Phase I study of 24-hour continuous intravenous infusion of recombinant human tumor necrosis factor.

Sixteen patients with cancer were treated with a 24-h continuous intravenous infusion of recombinant human tumor necrosis factor (rHuTNF) to investigate the spectrum of side-effects, the maximum tolerated dose, the pharmacokinetics, and possible antitumor effects. Fever, chills, and flu-like symptoms were the most common side-effects. The maximum tolerated dose was 6 x 10(5) U/m2 (261 micrograms/m2). Severe hypotension, fluid retention, watery diarrhea, and central nervous deficits culminated in a profound prostration as the dose-limiting toxicity. No allergic reactions, positive skin tests, or antibodies against rHuTNF were observed. Plasma levels of rHuTNF were detected at doses of greater than or equal to 3 x 10(5) U/ml2. Maximal plasma levels were 19 U/ml (8.2 ng/ml). No objective tumor responses were observed.

Adult↗
PubMed1987

Lectin binding pattern of Hodgkin disease-derived cell lines in comparison to other human cell lines.

The three Hodgkin disease-derived cell lines L 428, L 540, and L 591 were characterized in their carbohydrate epitope composition by a panel of lectins. Nine other human cell lines were tested in comparison to the Hodgkin (H) and Sternberg Reed (SR) cells: promyelocytic (HL 60), lymphoblastoid, myeloma, histiocytic lymphoma (U 937), and other non-Hodgkin lymphoma cell lines. Twenty-four different fluoresceinated lectins bound to the Hodgkin and other cell lines in different percentages of positive cells and with varying intensities. Lotus lectin and a monoclonal anti-Lewis blood group X antibody showed very similar binding patterns (L 428, L 540, HL 60, U 937). Soybean agglutinin stained only L 428 and L 540, although nearly all were positive after neuraminidase treatment. Cell lysis of the three H cell lines resulted in a very similar electrophoretic mobility pattern of proteins. In addition, staining of transblotted glycoproteins with biotinylated concanavalin A by avidin peroxidase reaction revealed corresponding bands. Differences were seen with Lotus staining. In summary, the origin of H cells is still unknown, but there is obviously some relationship in the glycoconjugate profile to the myelohistiocytic lineage.

Cell Line↗
PubMed1986

Cytogenetic investigations in Hodgkin's disease: I. Involvement of specific chromosomes in marker formation.

Cytogenetic studies were performed in five Hodgkin-derived permanently growing cell lines, as well as in bone marrow cells from two Hodgkin patients, one of which suffering from acute myeloid leukemia after Hodgkin's disease. No consistent and common marker chromosome was found, but certain chromosome regions seemed to be nonrandomly involved in marker formation. These are chromosome bands 7q22, 7q32, 7q36, 2q33, 1p22, 11q21/23, 14q32, 15p12, and 21q21. The importance and significance of these chromosomal findings are discussed in reference to data from the literature.

Chromosome Aberrations↗