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H Pralle

Publications and source records attributed to H Pralle.

At least 37 records · Page 2Linked to original sources

Expression of the nerve growth factor receptor c-TRK in human myeloid leukaemia cells.

Nerve growth factor (NGF) is of major importance for the survival, development and maintenance of peripheral sympathetic and central neuronal tissue. Most of the cellular effects are mediated by binding to their high-affinity receptor c-TRK, a transmembrane receptor tyrosine kinase. C-TRK protein has been detected in neuronal tissue and also in mast cells, monocytes and some haemopoletic progenitor cells. Here we report c-TRK gene expression in myeloid leukaemic cell lines (HEL, K562 and KG-1) and for the first time in the primary leukaemic cells of 44% (n = 59) of patients with acute myelogenous leukaemia (AML). Moreover, in the human promyelocytic cell line HL-60, c-TRK expression was inducible by differentiation induction with tetradecanoyl-phorbol 13-acetate (TPA). In c-TRK gene-expressing cells the transmembrane receptor tyrosine kinase was detectable by Western blotting and by in vitro kinase assay. In the AML group, c-TRK expression was not correlated to the FAB-classified morphology or any other clinical parameter. In all cases tested we could not detect NGF mRNA by means of reverse transcriptase PCR, excluding an autocrine loop involving the TRK/NGF receptor-ligand system in leukaemogenesis. Our results show another example of possible communication between neuronal and haemopoietic tissue. However, we still lack positive evidence of a c-TRK function in haemopoiesis.

Blotting, Western↗

Bronchoalveolar and systemic cytokine profiles in patients with ARDS, severe pneumonia and cardiogenic pulmonary oedema.

The aim of this study was to investigate whether bronchoalveolar lavage (BAL) and serum levels of proinflammatory cytokines discriminate between different entities of patients with acute respiratory failure. BAL and circulating concentrations of interleukin-6 (IL-6), interleukin-8 (IL-8) and tumour necrosis factor-alpha (TNF-alpha) were measured in 74 mechanically-ventilated patients and 17 healthy controls. Patients were classified as cardiogenic pulmonary oedema (CPO), acute respiratory distress syndrome (ARDS), primary severe pneumonia (PN) and a combined group (PN+ARDS). In all patients with ARDS and/or PN, markedly elevated BAL levels of IL-6 and IL-8 were detected, which were significantly greater than levels in CPO and healthy controls. Absolute quantities and time-course of these cytokines did not differentiate between the absence and presence of lung infection, or different categories of PN. Similarly, circulating IL-6 levels were comparably elevated in patients with ARDS and/or PN, whereas circulating IL-8 concentrations were inconsistently increased. TNF-alpha was rarely detected in BAL samples, but increased serum concentrations were measured in ARDS and/or PN patients. Bronchoalveolar lavage levels of interleukin-6 and interleukin-8, but not tumour necrosis factor-alpha, and serum concentrations of interleukin-6 are consistently elevated in acute respiratory distress syndrome and/or severe pneumonia, discriminating these entities from cardiogenic pulmonary oedema. Alveolar and systemic cytokine profiles do not differentiate between acute respiratory distress syndrome in the absence of lung infection and states of severe primary or secondary pneumonia, which evidently present with comparable local and systemic inflammatory sequelae.

Acute Disease↗

Randomized study of the combination of hydroxyurea and interferon alpha versus hydroxyurea monotherapy during the chronic phase of chronic myelogenous leukemia (CML Study II). The German CML Study Group.

It is the long-term goal of the German CML Study Group and of the Süddeutsche Hämoblastosegruppe (SHG) to improve survival of patients with chronic myelogenous leukemia (CML). In a first randomized study (CML Study I) monotherapies with hydroxyurea or interferon alpha (IFN-alpha) were compared with a standard busulfan regimen with regard to duration of the chronic phase and survival. The main results of this study were published, 1-3 and a long-term follow up is planned. In a second randomized study the effect of the combination of IFN-alpha and hydroxyurea versus hydroxyurea monotherapy on survival is being investigated. This paper provides a first preliminary report on the study concept, patient recruitment, state of documentation and initial patients' characteristics 9 months after closure of the study.

Adult↗

Clinical experience with fludarabine and its immunosuppressive effects in pretreated chronic lymphocytic leukemias and low-grade lymphomas.

Fludarabine monophosphate (FAMP) is a new adenine nucleoside analogue with a promising efficacy in B-cell chronic lymphocytic leukemia (B-CLL) and low-grade non-Hodgkin lymphomas (NHLs). Here, the clinical experience and side effects with FAMP are reported in 77 patients with pretreated CLL (59 B-CLL, 2 T-CLL) and low-grade NHLs (9 immunocytic lymphomas including 5 Waldenström's macroglobulinaemia, 2 centrocytic (cc) and 5 centroblastic-centrocytic (cb-cc) NHLs). 70/77 patients are evaluable for response. All except 8 patients were pretreated with one to four different regimens and had progressive disease. FAMP was administered at a dosage of 25 mg/m2 daily for 5 days as 30 minute infusion every fifth week. Partial (PR) or complete remission (CR) was achieved in 38/56 (68%) and 3/56 (5%) of evaluable patients with CLL, respectively. In 7/8 (1 x CR, 6 x PR) evaluable patients with immunocytic lymphoma and in 3/6 (3 x PR) patients with cc or cb-cc lymphoma remissions were obtained. The probability of progression-free survival was 66% and the event-free survival was 25% and 22% at 12 and 18 months. The median progression-free survival until relapse or death, however, was only 7 months (2-20+). Major toxic effects included infections in 22 patients (grade 3 and 4 WHO), granulocytopenia (mainly grade 3) and nausea in 8 patients (mainly grade 1). 19/22 patients were in PR at the time of occurrence of infectious complications. Meanwhile, 14 patients died due to septicaemia, pneumonia or other infections. Nine patients developed severe septicaemia, 4 patients had pneumocystis carinii or aspergillus pneumonias. The high infection rate may not only be due to hypogammaglobulinaemia and granulocytopenia induced by FAMP but also to a remarkable decrease of CD4+ cells from a median of 2479 to 241 CD4+ cells/microliters after 6 cycles of FAMP. In one case a tumor lysis syndrome was observed. No CNS toxicity was noted. It is concluded that FAMP is effective even in patients with advanced CLL and low-grade NHLs refractory to multiple chemotherapy regimens. However, FAMP has a marked suppressive effect on granulocytes and T-lymphocytes, predominantly CD4+ lymphocytes.

Adult↗

Randomized comparison of interferon-alpha with busulfan and hydroxyurea in chronic myelogenous leukemia. The German CML Study Group.

As curative bone marrow transplantation is available only to a minority of patients with chronic myelogenous leukemia (CML), drug therapy remains of central interest. Several nonrandomized studies have suggested that interferon-alpha (IFN) may prolong survival in CML. In a randomized multicenter study the influence of IFN versus busulfan or hydroxyurea (HU) on survival of Philadelphia-positive (Ph+) CML was examined. A total of 513 Ph+ patients were randomized for treatment as follows: 133 for IFN, 186 for busulfan, and 194 for HU. IFN-treated CML patients have a significant survival advantage over busulfan-treated (P = .008), but not over HU-treated patients (P = .44). The longer survival is due to slower progression to blast crisis. Median survival of IFN-treated patients is 5.5 years [5-year survival, 59%; 95% confidence interval (CI), 48%-70%], of busulfan-treated patients, 3.8 years (5-year survival, 32%; CI, 24%-40%), and of HU-treated patients, 4.7 years (5-year survival, 44%; CI, 36%-53%). Patients who continue on IFN survive longer than those in whom IFN is discontinued before blast crisis (P = .007). Complete hematologic IFN-responders have a survival advantage over partial responders or nonresponders (P = .02). Cytogenetic IFN-responders have no significant survival advantage over nonresponders (P = .2). Patients who attain white blood cell (WBC) counts of 10 x 10(9)/L or less have a survival advantage in the IFN (P = .007) and HU (P = .05) groups. Whereas toxicity in the IFN group was considerably higher than in the busulfan or HU groups, long-lasting cytopenias necessitating discontinuation of therapy as observed with busulfan have not been seen with IFN or HU. The problems of conventional prognostic scores (Sokal's score, Score 1) that we observed in IFN-treated patients support the idea that IFN changes the natural course of CML. We conclude that, with regard to survival of CML in the chronic phase, IFN is superior to busulfan and as effective as HU. Whether and to what extent IFN is superior to HU appears to depend, at least in part, on the degree of WBC suppression by HU-therapy and on the risk profile of the patients.

Adolescent↗

Multiparameter flow cytometric analysis of inflammatory cells contained in bronchoalveolar lavage fluid.

Quantitative analysis of surface molecule expression on viable alveolar macrophages (AM) by use of flow cytometry is hampered by non-specific antibody binding to various AM FcIgG receptors as well as extensive and heterogeneous autofluorescence of this cell type. The following approaches were undertaken to circumvent these obstacles. FcIgG receptors were blocked by excess human immunoglobulin. The use of a long wave-emitting dye (phycoerythrin/cyanine-5 tandem conjugate) permitted avoidance of the peak (green) AM autofluorescence range. Moreover, a cell-by-cell compensation for the remaining red autofluorescence background was employed. This was based on two facts: (i) strict correlation between green (F488/530) and red autofluorescence (F488/660) for all AM populations investigated; and (ii) neglectable overlap of the antibody-associated red fluorescence into the 530 nm autofluorescence detection wavelength. A fraction of the green autofluorescence (F488/530; channel 1) was then subtracted from the red fluorescence (F488/660; channel 2) on a cell-by-cell basis using standard two colour fluorescence compensation circuits. The validity of this FACS technique was confirmed by comparison with immunocytochemical staining and a reverse rosetting method. On AM lavaged from carcinoma-bearing but otherwise disease-free human lungs, the pattern of surface antigen expression was assessed with a panel of monoclonal antibodies. When applying to complex mixtures of bronchoalveolar lavage cells, the autofluorescence was employed to separate AM from granulocytes and lymphocytes. In conclusion, the presently described FACS technique allows quantitative immunostaining of surface molecules on AM, even when present in low copy numbers on highly autofluorescent cells originating from smokers.

Bronchoalveolar Lavage Fluid↗

Immune electron-microscopy study of the trimeric glycoprotein (CD 103) of hairy cell leukemia using the Ber-ACT8 monoclonal antibody.

We describe a method which makes it possible to study the expression of the trimeric glycoprotein (TGP, CD 103) on the surface of hairy cells (HCs) by electron microscopy (e.m.). The monoclonal antibody (mAb) Ber-ACT8 was used to identify the TGP. By testing mucosa of the small intestine, we found that a prefixation incubation with Ber-ACT8 was necessary. After isolation with a density gradient, Ber-ACT8 incubation, and fixation, the peroxidase-anti-peroxidase (PAP) method was used to make the TGP visible. The HCs showed a clearly discernible stain on their surface, a fairly constant distribution of the TGP, and a very good ultrastructural preservation. This method makes it possible to demonstrate the TGP or other unfixable antigens by e.m.

Aged↗

Phagocytosis of viable Candida albicans by alveolar macrophages: flow cytometric quantification.

The phagocytic capacity of blood leukocytes may be assessed by flow cytometric techniques using fluorochrome-labeled particles including viable microorganisms. Application of this approach to alveolar macrophages (AM) is hampered or even rendered impossible by the strong autofluorescence of this cell type, superimposing the fluorescence intensity of the labeled phagocytic targets. Viable Candida albicans were loaded with the membrane-permeable fluorescent dye carboxy-seminaphtorhodafluor 2/acetoxymethylester (carboxy-SNARF 2-AM), which is cleaved intracellularly to generate the membrane-impermeable derivative carboxy-SNARF 2. Fluorescence was excited with the 488-nm line of an argon-ion laser, and the emission peak at 633 nm was used for quantification of dye-associated fluorescence. Rabbit and human AM were labeled with fluorescein isothiocyanate-coupled monoclonal mouse anti-macrophage antibodies. After coincubation of macrophages and yeast, 4% paraformaldehyde plus 0.5% EDTA in phosphate-buffered saline was used to stop the phagocytic process and detach adherent yeast from the AM surface. Macrophages loaded with yeast displayed a shift from monochromatic (green) to dual (green and red) fluorescence. The percentage of yeast-positive AM and red fluorescence intensity of phagocytosing macrophages were quantified. Yeast opsonization with serum or anti-Candida immunoglobulins was a prerequisite for phagocytosis. Under optimized conditions (0.5-10% serum; 60 min yeast-AM incubation; yeast-AM ratio 8:1 to 12:1), 71-91% of the AM were involved in the phagocytic process. Yeast engulfment was completely inhibited by N-ethylmaleimide and iodoacetic acid.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Unmodified phosphodiester antisense oligodeoxynucleotides to the BCR-ABL junction do not suppress Philadelphia-positive clonogenic cells.

The BCR-ABL fusion gene is directly involved in the pathogenesis of chronic myeloid leukemia (CML). Specific inhibition of the BCR-ABL gene expression with antisense oligodeoxynucleotides has been shown to have profound effects on cell growth in vitro. We examined antisense phosphodiester oligonucleotides (16-mers at a concentration of 60 micrograms/ml) spanning the two possible junction sites K28 (b3a2) and L6 (b2a2) in a clonogenic assay. Single colonies from 9 patients with CML and from patients with normal bone marrow were screened for BCR-ABL expression with a new 'single-tube nested PCR' method. There was a marked reduction in colony number in the CML group and a lesser growth inhibition in the control group. The number and percentage of BCR-ABL-positive colonies, however, was not reduced in the CML group. This indicates a nonspecific growth inhibition only.

Base Sequence↗

Blastic phase chronic myeloid leukemia with a four-break rearrangement: t(11;9)(9;22)(q23;p22q34;q11).

Chromosome analysis of bone marrow (BM) aspirate from a 36-year-old man with chronic myeloid leukemia (CML) in blastic phase (BP) showed a four-break rearrangement t(11;9)(9;22)(q23; p22q34;q11), which can be considered a t(9;22)(q34;q11) and a secondary t(9;11)(p22;q23). It is not surprising that additional chromosome abnormalities occur in patients with Ph-positive CML in BP, but it is of interest that t(9;11)(p22;q23), characteristic of acute myeloid leukemia French-American-British (FAB) type M5 (ANLL-M5) was observed. The possible meaning of this additional change in BP of CML is discussed.

Adult↗

Randomized comparison of busulfan and hydroxyurea in chronic myelogenous leukemia: prolongation of survival by hydroxyurea. The German CML Study Group.

In a randomized multicenter study the influence of hydroxyurea versus busulfan on the duration of the chronic phase and on survival of chronic myelogenous leukemia (CML) was determined. In addition cross resistance and adverse reactions of the drugs were analyzed. From July 1983 to January 1991, 441 CML patients were randomized to receive hydroxyurea or busulfan. Of these, 90.7% were Philadelphia positive; 25.7% were low, 38.2% intermediate, and 36.2% high risk patients according to Sokal's score. The median survival of the busulfan treated Philadelphia-positive patients is 45.4 months and of the hydroxyurea group 58.2 months (P = .008). The survival advantage for the hydroxyurea treated patients is recognized in all risk groups. Sixty four patients reached therapy resistance before blast crisis and were crossed over to the alternative drug. The 23 patients with primary hydroxyurea had a median survival of 5.6 years, the 41 patients with primary busulfan therapy a median survival of 2.7 years (P = .02). Adverse reactions were less frequent with hydroxyurea with no severe adverse effects (lung fibrosis, long lasting bone marrow aplasia). The analysis of white blood cell counts in the course of treatment showed lower counts in the hydroxyurea patients. We conclude that hydroxyurea is superior to busulfan in therapy of CML in chronic phase and should be used as first line therapy. Busulfan may have a role as secondary therapy after hydroxyurea resistance or intolerance.

Blast Crisis↗

Increased risk of acute myelogenous leukemia (AML) and chronic myelogenous leukemia (CML) in a county of Hesse, Germany.

The incidence of acute and chronic myelogenous leukemia has been compared for the two neighbouring regions of Marburg and Giessen in Hesse (Germany). The investigation was based on the incident cases of the years 1983-1989 which have been diagnosed in the hematological departments of the universities of the two regions. The epidemiological evaluation of the data has been carried out in terms of a historical follow-up study, and shows an increased relative risk for the region around Marburg with a particular elevation for one community within this region. Potential determinants are discussed and focus on trinitrotoluene (TNT) and decomposition products which are known to contaminate the soil of this community, in some places severely, due to insufficient removal of remnants of the TNT production in large underground plants during World War II.

Adult↗

The German CML study, comparison of busulfan vs. hydroxyurea vs. interferon alpha and establishment of prognostic score 1.

From July 1983 to January 1991 a total of 622 patients were randomized (585 eligible) to compare the effects of hydroxyurea, interferon alpha (IFN), and busulfan on the duration of chronic phase, and survival. Further goals included the determination of prognostic parameters. 598 CML patients were documented and 575 evaluable. The Ph-status was known for 547 patients. 89.4% of the patients were Ph-positive (+). 11% had additional chromosome aberrations. The median survival of Ph+ patients by now is 4.2 years, that of Ph-patients 1.4 years. Ph-negative patients are older, tend to have lower cell counts and, as a group are more ill at diagnosis. A survival difference of about one year is expected between busulfan and hydroxyurea treated patients. Prospectively evaluated age, organomegaly related symptoms, Karnofsky index, extramedullary manifestations, number of erythroblasts and percent of circulating blasts proved to be of prognostic significance. A prognostic score (score 1) was determined which was superior to Sokal's score in the study population. 164 patients were randomized to receive IFN. In 54 patients (33%) IFN had to be terminated because of adverse effects, therapy resistance or other reasons. Clinically relevant neutralizing antibodies were detected in 9 cases. Most frequent adverse events were flu-like symptoms in 74%, gastrointestinal symptoms in 52%, and neurologic-psychiatric symptoms in 30% of patients. Reduction of the Ph-chromosome was observed in 13% of evaluable patients (10 of 75). In 4 patients complete cytogenetic remissions were observed, in three of these ongoing. Cytogenetic responders have a survival advantage. Interferon treated Philadelphia-negative CML patients have no survival disadvantage. The study is expected to allow statements as to the advantages or disadvantages of the use of busulfan, hydroxyurea and IFN in the treatment of CML as well as to the reliability of prognostic markers.

Adult↗

Effective natural interferon-alpha therapy in recombinant interferon-alpha-resistant patients with hairy cell leukemia.

To explore the relationship between anti-interferon-alpha (anti-IFN-alpha) antibodies and loss of clinical responsiveness to IFN-alpha treatment, we examined sera from 59 patients with hairy cell leukemia who responded to therapy with recombinant IFN-alpha-2a (rIFN-alpha-2a). During the first 2 years of therapy, 10 patients developed rIFN-alpha-2a-neutralizing and 15 rIFN-alpha-2a-binding antibodies. Nine of the 59 initially responding patients became resistant to rIFN-alpha-2a and suffered a relapse of the disease at 7 to 24 months of treatment. All nine relapsing patients tested positive for both neutralizing and binding antibodies with titers above 400 INU/mL, while none of the antibody-negative patients relapsed. Six patients with detectable binding antibody titers below 400 INU/mL continued to respond to treatment. By measuring the IFN kinetics and the levels of the IFN-induced Mx-homologous protein in mononuclear cells after a single injection each of rIFN-alpha-2a and nIFN-alpha the IFN antibodies of eight of the nine resistant rIFN-alpha patients were found to be highly specific for rIFN-alpha-2a. Therefore, these eight patients were switched to natural IFN-alpha (nIFN-alpha) therapy at doses of 3 million IU, three times a week. All eight patients responded to treatment with nIFN-alpha, achieving durable objective responses similar to those obtained previously with rIFN-alpha-2a. These data clearly demonstrate that rIFN-alpha antibody-positive patients can effectively be treated with nIFN-alpha.

Adult↗

[Immunologic studies in patients with ovarian carcinoma during radio-chemotherapy. I. Studies of lymphocyte subpopulations].

In this article we have studied the behaviours of different lymphocyte subpopulations (T11, T8, T4, B4 and B1) in the peripheral blood of 60 patients suffering from ovarian cancer during radio- and chemotherapy with the APAAP-technique. The most important results of our study are that compared with the chemotherapy the radiotherapy causes greater lymphocyte depression, that the subpopulations of T-lymphocyte with the exception of T8 show greater radio-sensitivities than B-lymphocyte, that T8-subpopulation is not radio-sensitive, and that the T11-, T4-, B4- and B1-subpopulations of the patients at stage I and II can recover from the depression caused by radiation much better than the corresponding subpopulations of the patients at stage III and IV.

Adult↗