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Biomedical subjects

E Fritz

Publications and source records attributed to E Fritz.

At least 55 records · Page 3Linked to original sources
PubMed1990

[Erythropoietin treatment of tumor-associated anemia in patients with multiple myeloma].

Anemia of malignancy is a complication of neoplastic disease which causes impairing symptoms and often requires blood transfusions. In this clinical trial, we have treated 13 patients suffering from chronic anemia of malignancy and multiple myeloma with recombinant human erythropoietin (rHuEPO) three times a week. Eleven patients responded to the treatment by appropriate increases of their hemoglobin levels and the eventual correction of the anemic state, one non-responding patient had to terminate the treatment early because of transfusion requirements. Under rHuEPO therapy, the evaluated parameters of iron metabolism indicated the enhanced synthesis of hemoglobin. The symptoms of anemia subsided in the responding patients and most of them reported a hightened subjective sense of well-being. No adverse side effects, particularly no episodes of hypertension, were observed in any patient.

Aged↗
PubMed1990

Long-term alpha-interferon therapy in myelodysplastic syndromes.

The myelodysplastic syndrome (MDS) is characterized by a high probability of leukemic transformation and frequently lethal infections or bleeding episodes. Up to now, no generally accepted form of therapy has been established for MDS. Previous trials with alpha-interferon (IFN-alpha) have shown some beneficial effects. We studied the effects of long-term application of IFN-alpha at higher dosages in patients with "low-risk" MDS. Ten patients were included in the study; eight were treated for a period of 6-36 months. IFN-alpha was administered at a median dosage of 9, 6, 4 mU/week during the first, second, and third year, respectively. Response was determined by the status of peripheral blood and bone marrow. Prolonged exposure to IFN resulted in a response rate of 3/10 (30%). In an additional case, disease progression was retarded during the third year of therapy. The incidences of infections and bleeding events subsided notably. After the withdrawal of IFN, hematological and clinical parameters rapidly deteriorated in some patients. The observed improvement of the patients' susceptibility to infections possibly prolongs their survival and seems to justify further trials on IFN treatment in patients with MDS.

Aged↗
PubMed1989

Long-term interferon therapy for thrombocytosis in myeloproliferative diseases.

31 patients with thrombocytosis associated with myeloproliferative disorders were included in a prospective trial of long-term interferon therapy. 6 patients (19%) had side-effects which required withdrawal of interferon within one year. 22 patients (71%) achieved and maintained a complete response (platelet count less than 440 x 10(9)/l) for at least twelve months, with reduction or abolition of symptoms associated with thrombocytosis and a significant fall in bone-marrow megakaryocytes. At twelve months, 25 patients were randomly allocated to maintenance or withdrawal of interferon. Thrombocytosis recurred rapidly when treatment was stopped, but a second remission could be achieved by resumption of interferon therapy.

Aged↗
PubMed1989

Early-onset thrombocytopenia during combination chemotherapy in testicular cancer is induced by vinblastine.

Platelet kinetics were studied in 70 patients with testicular cancer to elicit the agent responsible for chemotherapy-induced transient early-onset thrombocytopenia; 204 treatment courses were analyzed using three different therapy protocols, which contained vinblastine and bleomycin either alone or in combination with cisplatin. Platelet count decreased significantly from the start of vinblastine administration reaching its nadir on the third day of therapy in each of the three treatment groups. Between day 4 and day 10 of the treatment cycle, platelet counts steadily increased even in patients still receiving continuous bleomycin infusions. The conclusion that the observed early-onset thrombocytopenia was caused by vinblastine was substantiated by the outcome of two additional examinations. Platelet half-life was significantly shortened 24 hours after vinblastine administration and electron microscopy revealed a dissolution of cytoplasmatic microtubules with loss of the typical discoid shape of platelets within 15 minutes after the start of therapy. Both findings occurred irrespective of the specific treatment protocol, i.e., even after nothing but vinblastine had been given. These results strongly suggest that vinblastine is the main cytostatic agent responsible for the transient early-onset thrombocytopenia observed during chemotherapy of testicular cancer.

Adolescent↗
PubMed1989

VMCP chemotherapy with or without interferon-alpha-2 in newly diagnosed patients with multiple myeloma.

Fifty-two previously untreated patients with multiple myeloma were randomized to either a combination of recombinant interferon (rIFN) alpha-2 and chemotherapy or chemotherapy alone. Patients were treated with vincristine, melphalan, cyclophosphamide and prednisolone every 4-6 weeks. In the combined treatment arm rIFN was administered concurrently with chemotherapy as well as during chemotherapy free intervals. The combined regimen effected 17/21 (80.9%) responses as compared to 19/27 (70.4%) responses in VMCP treated patients. Addition of rIFN to chemotherapy did not enhance hematologic toxicity. These findings suggest a somewhat higher rate of objective response in the VPMC + rIFN group, although a significant improvement in median survival by adding rIFN to conventional first line polychemotherapy in myeloma patients has not yet been achieved.

Adult↗
PubMed1989

Combined alpha-2C-interferon/VMCP polychemotherapy versus VMCP polychemotherapy as induction therapy in multiple myeloma: a prospective randomized trial.

Thirty-three previously untreated patients with multiple myeloma were randomized to either a combination of recombinant interferon-alpha-2C (rIFN-alpha-2C) plus vincristine/melphalan/cyclophosphamide and prednisone (VMCP) or VMCP chemotherapy alone. The combined regimen effected 67% responses and 26% minor responses, while 35 and 47% of VMCP-treated patients had a pathologically documented remission, respectively. Despite the somewhat earlier achievement and duration (12.0 vs. 8.0 months) of objective response, and the marginal survival benefit observed in the rIFN-alpha-2C + VMCP treatment arm, a significant improvement in therapeutic gain by adding a biologic response modifier to conventional first-line polychemotherapeutic drug treatment in myeloma patients has not yet been achieved. The combined regimen was well tolerated without unusual or unexpected toxic effects.

Adult↗
PubMed1988

Aluminum toxicity and forest decline.

The rate of root elongation in seedlings of Picea abies was drastically inhibited by exposure to AlCl(3) at 800 or 1200 mumol/dm(3) in nutrient solutions. A 35-day exposure to Al at 700 mumol/dm(3) reduced Mg and Ca in roots and needles of the seedlings. The Mg content of needles was reduced to levels considered to be critical for Mg deficiency. In investigations of (45)Ca uptake into roots, exposure to Al at 100-800 mumol/dm(3) reduced (45)Ca uptake by 77-92%, respectively. By using x-ray microanalysis, the distribution of Al, Mg, Ca, and K was found to be similar in roots of Picea abies seedlings grown in solution culture and in roots collected from declining spruce stands at Solling, F.R.G. In solution culture Al displaced Mg and Ca in the root cortex. A mechanism of Al toxicity for root growth and ion uptake is proposed, and its relevance to forest decline is discussed.

Journal Article↗
PubMed1988

Localization and toxic effects of cadmium, copper, and uranium in azolla.

The storage and distribution of copper, cadmium, and uranium and their effects on ionic contents in roots and shoots of Azolla filiculoides has been studied by x-ray microanalysis. The relative content of copper was eightfold higher in the root than in the shoot, suggesting low mobility of this metal in Azolla plant. Cadmium relative content in the shoot was similar to its content in the root, hence its mobility was relatively high. The absence of significant uranium quantities in the shoot and its relative high content in the root suggest the immobility of this metal from Azolla root. Cadmium formed precipitates with phosphate and calcium in xylem cells of the shoot bundle and caused a two- to threefold increase in the content of phosphate in the root. Uranium in roots and cadmium in shoots were associated with calcium. All three treatments caused losses of potassium, chloride, and magnesium from Azolla roots. Accumulation of heavy metals in Azolla and their mobility from the root to the shoot can be correlated with damage caused by the loss of essential nutrients.

Journal Article↗
PubMed1988

[Interferon therapy in multiple myeloma].

Natural leukocyte interferon and recombinant interferon alpha-2 have effected remission rates between 10 and 20% in the treatment of multiple myeloma. Response rates have been higher in untreated patients than in relapsing or primarily refractory cases. Patients with slowly proliferating tumors, early tumor stage or IgA-monoclonal protein seem to show increased sensibility to interferon as compared to patients without those characteristics. First trials using combined interferon chemotherapy regimens suggest that the toxicity associated with this treatment modality remains acceptable. At present, however, one cannot definitely decide whether and to which degree the combination therapy will improve the response rates.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1987

Magnetic resonance imaging of the spine in multiple myeloma.

The lower thoracic and lumbar spine of patients with multiple myeloma was examined by magnetic resonance imaging (MRI), plain radiography, and bone scintigraphy. Three independent investigators evaluated the power of these diagnostic methods to detect bone lesions in 192 vertebrae from 18 patients and in 60 vertebrae from 7 controls. 41 foci with abnormal signal intensity were detected by MRI; X-ray films showed osteolytic lesions in 4 vertebral bodies; and bone scanning was positive in 2 cases. The superiority of MRI in detecting myeloma-associated focal bone lesions was statistically significant, and in one case the lesions were confirmed at necropsy. Deviations in shape and height of vertebral bodies were slightly more easily visible on radiographs. Early detection of imminent medullary compressions in 2 patients led to successful radiotherapy before symptoms appeared.

Adult↗
PubMed1987

Interferon-alfa corrects thrombocytosis in patients with myeloproliferative disorders.

During previous therapeutic trials with interferon, decreased levels of peripheral platelet counts have been observed. Taking advantage of this effect, we investigated the efficacy of recombinant interferon (rec-IFN) in the treatment of thrombocytosis in myeloproliferative diseases. A total of 15 patients with polycythemia vera, essential thrombocytosis, or chronic myeloid leukemia received rec-IFN-alfa at initial doses of 25-70 x 10(6) units/week; maintenance therapy following week 8 of treatment consisted of 20-35 x 10(6) units/week rec-IFN. Observation periods ranged from 24 to 48 weeks. Significant reductions in the number of platelets were noted in all cases; 12/15 patients achieved platelet counts below 440 x 10(9)/l and maintained those normal values for at least 4 weeks. The number of bone marrow megakaryocytes, which had been increased prior to treatment, diminished during rec-IFN therapy, while the previously shortened platelet half-life further decreased with rec-IFN treatment. During rec-IFN-induced remission, the plasma levels of platelet factors, the activity of natural killer cells, and platelet aggregation showed changes between slight improvement and normal values. Severe side effects were only observed with the highest rec-IFN doses; dosage adjustments were effective in improving or eliminating all treatment-related symptoms. Rec-IFN may prove to be a valuable therapeutic alternative to cytostatic treatment of thrombocytosis in myeloproliferative disorders.

Aged↗
PubMed1986

Shortened platelet half-life in multiple myeloma.

Various defects in platelet function have been reported as being associated with multiple myeloma. In 30 myeloma patients and 15 healthy controls, we investigated platelet survival using in vitro labeling of autologous platelets with 111indium-oxine and measuring the in vivo kinetics of the radioisotope. Significantly shortened platelet half-life in patients averaged 73 hours, while platelet half-life in the healthy controls averaged 107 hours. In myeloma patients, serum levels of thromboxane B2, beta-thromboglobulin, and platelet factor 4 were significantly elevated; aggregation indices were within the pathological range; platelet counts and spleen-liver indices, however, were comparable to those of the healthy control group. No statistical correlation was found between platelet half-life and paraprotein concentrations. Our findings suggest an initial--so far unexplained--intravascular process of platelet activation and consumption that finally manifests in shortened platelet half-life. It seems that overt thrombocytopenia develops only when the compensatory capacity of the bone marrow finally becomes exhausted. Further studies should be able to elucidate the pathophysiologic processes involved.

Blood Platelets↗
PubMed1985

Treatment with recombinant interferon-alpha-2C: multiple myeloma and thrombocythaemia in myeloproliferative diseases.

Forty-two patients with multiple myeloma were allocated to two groups to receive either polychemotherapy with vincristine, melphalan, cyclophosphamide and prednisolone, or recombinant interferon-alpha 2C monotherapy. The response rate of 43% in the interferon group was significantly lower than that in the chemotherapy group (89%). Patients with stage I disease showed better response rates than those with stage II or stage III disease. Eleven patients with thrombocythaemia due to polycythaemia vera, chronic myeloid leukaemia or essential thrombocythaemia were treated with recombinant interferon-alpha 2C and complete remissions were achieved in 7 of the 8 evaluable patients. Side-effects were common on interferon therapy, but could be reduced by dose reduction and were reversed by cessation of treatment.

Adult↗
PubMed1984

A plasma clot culture system for growing and antiproliferative drug sensitivity testing of myeloma stem cells.

An easy-to-perform clonogenic culture system for myeloma stem cells is presented which approaches the patient's in vivo situation more closely and therefore seems particularly well-suited for antiproliferative drug sensitivity assays. Bone marrow cells are propagated in clotted autologous or allogenic plasma that is enriched with 2-mercaptoethanol, insulin, and synthetic nucleotides and co-factors for nuclear synthesis, no feeder layer or conditioned medium is necessary. Clusters and colonies consisting of between 8 and 60 cells readily formed within 6-8 days after cloning yielding a plating efficiency between 0.12 and 2.16%. A linear relationship between the number of cells plated and colony formation was found from 10(5) through 2 X 10(6) cells plated. The successful growth rate for 65 tests from 53 patients amounted to 90.8%. Morphological and histochemical examination of the clusters revealed lymphoid cells at various stages of maturation ranging from lymphocytic and lymphoblastoid to lymphoplasmacytic and plasma cells. Tumor origin of the clones was demonstrated by immunofluorescence studies in which Ig-positive cells stained only for the heavy and light chain isotypes identical to those of the patient's serum paraprotein. Anti-idiotypic antisera confirmed the patient's specific malignant phenotype of the colonies formed. The technique of the assay is described in detail.

Cell Division↗
PubMed1984

Prognostic relevance of cellular morphology in multiple myeloma.

Morphological characteristics of tumor cells have been employed in the prognosis of lymphomas and solid tumors. This report documents an attempt to predict survival from the known cytologic heterogeneity in multiple myeloma. Myeloma cells in bone marrow smears from patients at diagnosis were evaluated by assigning them to morphologically defined categories. Cox's multivariate regression model for censored survival data was used to generate optimal weights, which served as coefficients in two regression equations to estimate death risk from cellular morphology. Step-wise procedures excluded redundant parameters. "Myeloma morphology score" (MMS) discriminates significantly (p less than 0.0001) among 3 stages, with median survival times of 42.5, 30.7, and 9.1 mo. For clinical routine application, "myeloma progression score" (MPS), the weight sum of the proportion of plasmablasts and the extent of bone marrow plasma cell infiltration, is suggested as a simple prognostic tool. Its discriminative power is very high [p less than 10(-9)]. Median survival times of greater than 71.5, 23.4, and 6.1 mo were found for good, moderate, and poor risk groups, respectively. However, staging is not confined to three subgroups, grouping is flexible, and pairs of data can be matched. This fact may prove to be valuable in designing prognosis-controlled clinical trials or theoretical studies on cellular differentiation. Preliminary results suggest changes in morphology due to disease progression and/or the effect of therapy on tumor kinetics. Most importantly, staging according to MPS or MMS may facilitate the adaption of therapy to the current state of the disease in patients with multiple myeloma.

Austria↗