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Biomedical subjects

K Havemann

Publications and source records attributed to K Havemann.

At least 73 records · Page 4Linked to original sources
PubMed1991

Combined chemo- and radiosensitivity testing with ifosfamide and ACNU in human lung cancer cell lines.

The combination of radiotherapy and cytostatic drugs is of interest in the treatment of several solid tumors. In these preclinical investigations we tested whether ifosfamide and ACNU are able to enhance radiation effects. The experiments were performed by using the MTT assay. Two small cell and 2 non small cell lung cancer cell lines were involved. Ifosfamide, ACNU or both drugs together were tested in 6 different concentrations adjusted to the peak blood level. During the 1 hour drug incubation time, the cell lines were either irradiated with a single dose of 4 Gy or not. The main results were that ACNU possessed only little cytostatic activity in the cell lines under examination. In contrast, ifosfamide caused a dose related cytostatic activity in all cell lines. Concentrations of 26 micrograms/ml (NCC-SCLC H 82) or 10-12 micrograms/ml (3 other cell lines) were able to reduce the surviving cell fraction to less than 50% (IC50). While ACNU showed no clear outlined radiosensitizing properties, ifosfamide reinforced the radiation effects in 3 out of 4 cell lines indicating radiosensitizing properties of this drug. Synergistic effects of ifosfamide and ACNU have not been noticed. These preclinical investigations may constitute the basis for combined ifosfamide and irradiation therapy in future clinical trials.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

Effect of rhGM-CSF on haematopoietic reconstitution after chemotherapy in small-cell lung cancer.

In three consecutive pilot studies the effect of recombinant human granulocyte/macrophage-colony-stimulating factor (rhGM-CSF) on haematopoetic recovery after chemotherapy in patients with small-cell lung cancer was investigated. In study I, 20 patients received AIO chemotherapy (A, Adriamycin 25 mg/m2 on days 1 + 2; I, ifosfamide 2 g/m2 on days 1-5; O, vincristine 2 mg on day 1) at 4-week intervals either with or without rhGM-CSF (250 micrograms/m2 sc) from day 8 until recovery of leucocytes. Neither the degree nor the duration of myelosuppression was markedly influenced by rhGM-CSF. Suggesting that these disappointing results were caused by the late onset of GM-CSF application, in the following study we shortened chemotherapy to 3 days and started with GM-CSF on day 4. The main objective of this study was to test whether the earlier administration of GM-CSF allowed treatment intervals to be reduced or the dose to be escalated. After 10 patients had received a starting dose of AIO (A, 50 mg/m2 on day 1; I, 2 g/m2 on days 1-3; 0,2 mg on day 1) alternating with cisplatin (90 mg/m2 on day 1) and etoposide (150 mg/m2 on days 1-3), the dose of ifosfamide and etoposide was escalated to 2.5 g/m2 on days 1-3 and 200 mg/m2 on days 1-3 in the next 10 patients. Treatment was given at 2-week intervals when leucocytes were greater than 3500/mm3 and thrombocytes were greater than 100,000 mm3 on day 14. At each dose level patients were randomized to receive either rhGM-CSF 250 micrograms/m2 s.c. on days 4-12 or no GM-CSF. In this study, rhGM-CSF markedly shortened the duration of leukopenia. Reinstitution of chemotherapy on day 15 was possible at dose level 1 in 1/4 patients without and in 3/4 patients with GM-CSF, and at dose level 2 in 0/5 patients without and in 5/5 patients with GM-CSF. However, the degree of myelosuppression was not improved by GM-CSF. In a third study we tried to apply rhGM-CSF simultaneously with chemotherapy. After 3 patients had received GM-CSF starting on day 1 concurrent to AIO chemotherapy, we noticed an increase of myelosuppression with prolonged neutropenia and thrombocytopenia and stopped this investigation. Considering all patients included in these three consecutive pilot studies, there is no difference in response rates and survival between patients with and without rhGM-CSF treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1991

Hematopoietic reconstitution after high-dose chemotherapy and autologous nonfrozen bone marrow rescue.

The kinetics of marrow engraftment were analyzed in 50 patients with acute leukemia (21), malignant lymphoma (15), and solid tumors (14) after high-dose multiagent chemotherapy followed by autologous bone marrow transplantation (ABMT) with nonfrozen bone marrow. Unseparated heparinized whole bone marrow was stored in 10% CPDA1 at 4 degrees C for 72 h, then filtered and reinfused. The median number of nucleated cells reinfused was 1.6 x 10(8)/kg (range 0.5-3.8 x 10(8)/kg). All patients had a full hematopoietic reconstitution. Median time to achieve a neutrophil count greater than 500/microliters was 20 days (range 12-39) and median time to achieve an unsupported platelet count greater than 20,000/microliters was 20 days (range 10-55). The main factor associated with delayed engraftment was the number of prior chemotherapy cycles. We conclude that high-dose chemotherapy with nonfrozen ABMT is a safe procedure, without the requirement for costly cryopreservation facilities.

Acute Disease↗
PubMed1991

Insulin-like growth factor binding protein expression in human small cell lung cancer cell lines.

Insulin-like growth factor binding proteins (IGF-BP) are secreted by several human small cell lung cancer cell lines (SCLC). In order to identify the IGF-BPs from SCLC cell lines the RNA from 10 different SCLC cell lines was analyzed by Northern blot analysis with the probes for three different IGF-BPs, IGFBP-1, IGFBP-2, and IGFBP-3. No hybridization signal could be detected with the probes encoding for IGFBP-1 and IGFBP-3. The hybridization with different IGFBP-2-specific oligodeoxynucleotide probes and with the corresponding full-length cDNA showed that all SCLC cell lines which secreted IGF-BPs express IGFBP-2.

Base Sequence↗
PubMed1991

Analysis of prognostic factors in 766 patients with small cell lung cancer (SCLC): the role of sex as a predictor for survival.

The data of 766 patients participating in three German multicentre trials were analysed with regard to the relationship between baseline characteristics and prognosis in small cell lung cancer (SCLC). The central aim of this analysis has been to evaluate the role of gender as an independent prognostic factor in SCLC. The minimum follow-up period for the 652 male and 114 female patients was 36 months. Female patients were shown to have a higher complete remission rate (35% vs 25%), a superior median survival (ms) (12.1 months (mo) vs 9.8 mo), and a favourable 2-year survival rate (2ys) (19% vs 8%) to male ones. Various other prognostic factors have been proved to be significant, such as extent of disease, clinical performance status, and history of smoking, whereas weight loss prior to chemotherapy and age have been less important factors. We have been able to ascertain that women's responses were better than those of male patients independent of any other relevant prognostic variable. Furthermore, results were found to be even more advantageous for female patients with additional favourable prognostic parameters, i.e. for patients with limited disease (ms 15.2 mo vs 12.0 mo; 2ys 29% vs 9%) or with good performance status (ms 13.4 mo vs 10.4 mo; 2ys 24% vs 7%). A most remarkable observation was made in that the favourable prognostic effect of the female gender was restricted to patients aged less than 60 years (ms 13.3 mo vs 10.1 mo; 2ys 26% vs 5%), whereas for older women no advantages over men's results were established (ms 9.3 ml vs 9.1 mo; 2ys 8% vs 7%). A proportion of 32% of female patients with limited disease aged less than 60 years achieved a 3-year survival rate. We conclude (a) that sex constitutes a major prognostic factor in SCLC and is especially useful as a predictor for long-term survival, and (b) that the favourable prognostic value of the female sex is restricted to younger patients.

Age Factors↗
PubMed1991

Determining carboplatin/etoposide dosage in extensive stage small-cell lung cancer (SCLC).

In order to define the maximum tolerance level of combined carboplatin/etoposide dosage, patients with extensive stage small-cell lung cancer (SCLC) were treated with a fixed dose of carboplatin (300 mg/m2 iv on day 1) and escalating doses of etoposide starting with 80 mg/m2 iv on days 1-3. Five patients were given this starting and every following dose level. The daily dose of etoposide was increased in increments of 20 mg/m2 iv until severe myelosuppression occurred in 3 of 5 patients. Leuko- or thrombocytopenia WHO grade 3 or 4 occurred in 0/5 of the patients at the dose levels of 80 and 100 mg/m2, in 1/4 of the patients at the level of 120 mg/m2, in 2/5 of the patients at a level of 140 mg/m2, and 3/5 patients at a level of 160 mg/m2. Thus, increase in dosage was stopped at an etoposide dose of 160 mg/m2. Other side effects were mild and consisted predominantly of nausea and vomiting in 14/25 of the patients. The overall response rate was 40% with a 12% complete remission rate, median survival was 9.3 months and median progression-free survival totalled 4.3 months. These results indicate that combined carboplatin/etoposide is a well tolerated regimen in extensive-stage SCLC, with response rates comparable to those of other standard protocols. Using treatment intervals of 4 weeks the recommended dose of etoposide in combination with 300 mg/m2 carboplatin was identified as 140 mg/m2 iv for 3 consecutive days.

Aged↗
PubMed1991

Inhibition of neutrophil chemotaxis by elastase-generated IgG fragments.

IgG1 is cleaved in vitro by granulocyte elastase into Fc and Fab fragments. The elastase-specific Fc fragment has been previously detected in vivo. Biological activity of the fragments has been described in modulating neutrophil oxidative metabolism and enzyme release. To investigate further effects granulocyte chemotaxis (CT) was tested. The CT was assayed in Boyden chambers and the chemotactic index (CI) was calculated which represents the mean distance travelled by the activated cells. Stimulation of leucocyte CT by casein, activated serum and FMLP gives maximal values of delta CI = 46.7, 26.4 and 7.2 microns, respectively. Native IgG1 and the elastase-produced IgG fragments do not stimulate leucocyte CT. FMLP-stimulated CT is specifically inhibited by the elastase-produced Fc fragments. Addition of 7 nmol Fc to stimulus concentrations of 16 to 125 nM FMLP results in total inhibition of chemotaxis demonstrated by CI values which are lower than those for unstimulated cells. The inhibition of CT is concentration dependent in the range of 2 to 7 nmol Fc/10(6) PMN. Number and affinity of FMLP receptors are not influenced by Fc fragments, so Fc binds neither to FMLP nor the FMLP receptor. CT stimulated by casein shows a large portion of chemokinesis. Only at suboptimal casein concentrations do Fc and IgG have an inhibitory effect on CT (0.63 mg casein/ml, 10 nmol peptide/10(6) PMN). C5a-stimulated CT is not influenced by IgG or IgG fragments which indicates that the samples are not cytotoxic. So the FMLP and casein-stimulated CT is specifically inhibited by the elastase-produced Fc fragments in a low concentration range.

Binding Sites↗
PubMed1991

Gingival crevicular fluid elastase-inhibitor complex: correlation with clinical indices and subgingival flora.

This investigation analyzed, in a cross-sectional study, the possible relationship between gingival crevicular fluid (GCF) elastase-like protease (ELP) levels and the periodontal clinical parameters or the presence of specific bacteria in subgingival plaque. A total of 388 periodontal sites from 8 adult periodontitis patients were examined for plaque index (PII), gingival index (GI), pocket depth (PD) and alveolar bone loss (ABL). GCF ELP levels were determined as ELP alpha-1 protease inhibitor (ELP-alpha 1-PI) complex levels with a commercially available ELISA. Subgingival plaque samples were tested for the presence of Bacteroides gingivalis, B. intermedius and Actinobacillus actinomycetemcomitans by indirect immunofluorescence (IF) microscopy. GCF ELP-alpha 1-PI levels were then correlated with clinical periodontal indices and proportions of IF-positive bacteria per site. Statistically significant positive correlations were found between GCF ELP-alpha 1-PI concentrations and subgingival Bacteroides proportions. When the sites examined were analyzed depending on the level of each clinical parameter, the levels of these correlations changed. A. actinomycetemcomitans correlated highly (r = 0.716) with ABL for sites with low GI score. The correlations between GCF ELP-alpha 1-PI and B. gingivalis (r = 0.642) or B. intermedius (r = 0.774) were the highest for ABL less than or equal to 20% and PD less than or equal to 3 mm, respectively. The strong association between GCF ELP-alpha 1-PI concentrations and subgingival bacteria previously associated with advancing periodontitis indicates that measurement of GCF ELP-alpha 1-PI concentrations may be useful in the evaluation of periodontal sites, especially those with very little or no tissue destruction.

Actinobacillus↗
PubMed1991

The role of membrane contact in hemodialysis-induced granulocyte activation.

Besides complement, interleukin-1 and beta 2-microglobulin, activation of granulocyte function has been found out to be the major parameter in the determination of dialyzer biocompatibility. Unfortunately, the term 'granulocyte activation' has been widely used without restriction to distinct functions or definition of the related metabolic pathways. Therefore, the present study aims to elucidate the influence of hemodialysis (HD) pure membrane contact on granulocyte O2- release. The activation of this metabolic pathway which is also known as the so-called oxidative burst has been generally accepted as the initial signal in the granulocyte inflammatory activation cascade. Two membranes which have been previously shown to differ most widely in biocompatibility, cuprophane and polysulfone, have been selected. During HD with cuprophane the stimulatable O2- release was initially decreased, whereas polysulfone HD was effectless on granulocyte oxidative metabolism. The inhibition was due to a prestimulation of the granulocyte by pure interaction of the cell with the surface of the dialyzer membrane which could be proved by evaluating a plasma-free model. Activation of oxidative metabolism was strongly correlated with granulocyte adherence, showing a significantly higher rate of cell adherence in the case of cuprophane. Nevertheless, sheer forces were able to prevent granulocytes becoming adherent directly to the dialyzer membrane, but sheer forces were not able to influence the oxidative burst reaction, suggesting that the membrane-related stimulation of oxidative metabolism occurs immediately after a very short, possibly a single and hasty contact of the cell to the surface of the dialyzer membrane.

Aged↗
PubMed1991

Hemodialysis and blood coagulation: the effect of hemodialysis on coagulation factor XIII and thrombin-antithrombin III complex.

Blood membrane interaction during hemodialysis (HD) regularly leads to stimulation of leukocyte function and related release of granular enzymes. The present study aimed to investigate the possible influence of an HD-induced release of granulocyte elastase on blood coagulation. Therefore a highly sensitive substrate of polymorphonuclear elastase, the plasma coagulation factor XIII and its subunits A and S were determined in the course of HD. Consumption of both subunit A and S have been previously shown to be due to proteolysis by elastase, whereas a decrease in subunit A will be typical for thrombin activation. Furthermore, the thrombin-antithrombin III complex (TAT) acting as a predisposition parameter for thrombotic events was measured during HD treatment. Apart from a virtual fall in factor XIII total activity simulated by heparin, no significant HD-induced consumption of factor XIII could be observed. There was also no indication of an elastase- or thrombin-related change in subunit concentrations. Predialysis values of the TAT complex were generally elevated in HD patients, but only patients with acute renal failure showed a constant increase of TAT during HD. These findings suggest that HD patients are exposed to a latent activation of coagulation resulting in an elevated thrombogenetic risk mainly due to the underlying disease. An additional coagulatory stimulation by the HD procedure seems to be restricted to cases of acute renal failure.

Acute Kidney Injury↗
PubMed1991

Protein C degradation in vitro by neutrophil elastase.

Purified protein C is completely degraded into small peptides by in vitro incubation with purified elastase. Protein C is a rather sensitive substrate as degradation is already accomplished by low elastase concentrations (molar enzyme-to-substrate ratio 1:510) and short incubation periods (5 min-60 min). Protein C in a PPSB coagulation factor concentrate is equally degraded and similar split products are detected by blotting techniques. The protein C activity (measured by a chromogenic substrate) is faster reduced by elastase than the protein C concentration (measured by an ELISA). Incubation of normal plasma with high elastase concentrations (5.7 nmol/ml plasma) results in reduction of the protein C band while no split products are detectable. The pathophysiologic significance of the effects of elastase on protein C remains to be elucidated.

Blood Coagulation Factors↗
PubMed1991

Focal involvement of malignant lymphoma in the liver.

In this study the sonographic findings of 30 patients with hepatic lymphoma have been reviewed. Lesions have been confirmed by autopsy (n = 1), laparatomy (n = 1), sonographically guided biopsy (n = 15), and during long-term follow-up (n = 13). Ten patients had Hodgkin's disease (HD) and 20 non-Hodgkin lymphomas (NHL). Focal lesions, less than 3 cm in diameter, were seen in 20 patients. The remaining ten cases presented large-nodule transformation of the parenchymal texture. All lesions were predominantly hypoechoic with a halo sign in two cases. No diffuse involvement of the liver was observed, and no correlation between histological lymphoma subtyping and patterns of hepatic infiltration was found.

Adolescent↗
PubMed1990

Growth regulation by insulin-like growth factors in lung cancer.

Lung cancer is a major health problem, with over 38,000 new cases expected every year in West Germany. A more complete understanding of the biology of lung cancer will hopefully lead to therapeutic modalities. The possible autocrine growth regulation in small-cell lung cancer and non-small-cell lung cancer has been demonstrated for bombesin/GRP, vasopressin, neurotensin, EGF/TGF alpha, transferrin-related peptides and insulin-like growth factors. This contribution concentrates on recent data concerning binding sites, growth promoting effects and secretion of IGFs in lung cancer cell lines. The production of IGF-binding proteins which were also produced by lung cancer cell lines modifies the autocrine/paracrine model for IGFs since then proteins can either enhance or inhibit the effect of IGFs on tumor growth.

Humans↗
PubMed1990

Multiple myeloma of the bladder and vagina.

A case is described of multiple myeloma with involvement of the urinary bladder and vagina. The patient was admitted with hematuria and postrenal obstruction. She was treated successfully with local radiotherapy and combination chemotherapy with vincristine, Adriamycin (doxorubicin), and dexamethasone (VAD).

Aged↗
PubMed1990

NCAM: a surface marker for human small cell lung cancer cells.

Immunocytochemical and immunochemical techniques were used to study the expression of the neural cell adhesion molecule (NCAM) by human lung cancer cell lines. Intense surface staining for NCAM was found at light and electron microscopic levels on small cell lung cancer cells. The NCAM polypeptide of Mr 140,000 (NCAM 140) was detected by immunoblotting in all of 7 small cell lung cancer cell lines examined and in one out of two of the closely related large cell cancer cell lines: it was not detected in cell lines obtained from one patient with a mesothelioma, in two cases of adenocarcinoma, nor in two cases of squamous cell cancer. In contrast, neuron-specific enolase was found by immunoblotting in all the lung cancer cell lines tested and synaptophysin in all but the adenocarcinoma cell lines. These antigens were localized intracellularly. The specific expression of NCAM 140 by human small and large cell lung carcinomas suggests its potential as a diagnostic marker.

Biomarkers, Tumor↗
PubMed1990

Differentiation capacity of human non-small-cell lung cancer cell lines after exposure to phorbol ester.

Three cell lines of squamous-cell carcinoma and 3 of large-cell carcinoma origin were investigated for the expression of differentiation markers and functional parameters (proliferation, morphology, cornified envelope formation, involucrin staining, transglutaminase activity, adhesiveness and migration) under normal cell culture conditions and after treatment with the tumor promoter phorbol-12-myristate-13-acetate (PMA). Although all original tumors had been described as poorly differentiated by histological grading, we found significant heterogeneity in the expression of differentiation markers in cell culture. A systematic grading of the cell lines became possible only after PMA stimulation. PMA generally increased expression of differentiation markers in cell lines of comparably low grades of differentiation, as indicated by dose-dependent inhibition of proliferation and cloning efficiency, induction of squamous markers, and decreased adhesiveness and cell motility. In contrast, cell lines of apparently higher differentiation by these criteria showed little response to PMA. The results presented show that the assessment of differentiation capacity by comparison of differentiation markers under normal cell culture and PMA-stimulated conditions in established NSCLC cell lines allows for a refined cell culture grading, which might advance the classification and characterization of such cell lines which, otherwise, appear to be very heterogeneous. It may also help to correlate cellular functions with various states of differentiation in vitro.

Biomarkers, Tumor↗
PubMed1990

Sonographic patterns of the affected spleen in malignant lymphoma.

Sonographic examination showed spleen involvement in 43 patients with histological evidence of malignant lymphoma. In 23% of these cases the spleen was of normal size and 77% exhibited variable splenomegaly. Focal lesions could be seen in 27 patients, 16 exhibiting diffuse, small-nodule transformation of the sonographic parenchymal texture. Hodgkin lymphomas caused both focal (7 of 16) and diffuse (9 of 16), splenic lesions. All non-Hodgkin lymphomas of high-grade malignancy exhibited focal lesions, which are larger than 3 cm in diameter in 11 out of 13 patients. In non-Hodgkin lymphomas of low-grade malignancy, focal sites and diffuse destruction of splenic tissue texture were found, lesions of under 3 cm in diameter (11 of 13) being characteristic of this subtype.

Adult↗