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Biomedical subjects

K Havemann

Publications and source records attributed to K Havemann.

At least 199 records · Page 11Linked to original sources

Production of five human lymphokines (granulocyte-macrophage colony stimulating factor, interferon-gamma, interleukin 2, macrophage cytotoxicity factor and macrophage migration inhibitory factor) from Con A stimulated lymphocyte cultures in bioreactors.

Cultivation parameters for the production of five lymphokines, granulocyte-macrophage colony stimulating factor (GM-CSF), interferon-gamma (IFN-gamma), interleukin 2 (IL-2), macrophage cytotoxicity factor (MCF), and macrophage migration inhibitory factor (MIF) from human spleen cells or peripheral blood lymphocytes were optimized. Cultivation was done in bioreactors containing up to 200 ml of medium, usually serum-free. The reactors were equipped with surface aeration facilities, stirrers and oxygen electrodes. Whereas stirring speed alone did not influence the yields of lymphokines, good aeration was especially beneficial for high IL-2 yields. However, all lymphokines were also produced under anaerobic conditions. The concentration of the mitogen concanavalin A was mainly critical for optimal IL-2 release. Optimal cell concentrations varied from 5 X 10(6)/ml (for GM-GSF and MCF) to 10 X 10(6)/ml (for IL-2 and IFN-gamma). It was possible to increase the yields of individual lymphokines 3 to 10-fold per batch of lymphocytes by a reinduction procedure which involved a change of medium and mitogen every 24 hrs. Reinduction was possible up to 4 times, especially when serum was present in the culture media.

Cells, Cultured↗

[Localized edema following cytostatic therapy].

In a phase II trial for non-small cell carcinoma of the lung and squamous cell carcinoma of the head and neck 16 patients were treated with a 3 drug combination chemotherapy: Cis-platinum, VP16, and vindesine. During therapy 4 patients suffered from localized transitory edema. This side effect has not been reported yet.

Adult↗

[3 multicenter phase II studies of the treatment of small cell bronchogenic carcinoma (incl. AIO studies BI + BII)].

Between March 1979 und January 1983 122 patients with small-cell carcinoma of the lung were treated with different polychemotherapy regimen. 33 patients received VP-16-213 (etoposid), ifosfamide and vindesine (VPIV). 37 patients were treated with adriamycin, cisplatin and vincristine (APO). A third 3-drug combination, cyclophosphamide, methotrexate and CCNU (CMCC), was given to the remaining 52 patients alternating with the two other regimen. Response rates varied between 61% for the APO regimen and 85% for the VPIV regimen. The median survival was 10 months for patients treated with VPIV or APO and 12 months for patients treated with alternating drug combinations. This difference was not statistically significant. The rate of long-term survivors (longer than 2 years after diagnosis) was 9.9%. Side effects were seen more frequently in the group treated with APO.

Adolescent↗

Acute allergic reaction due to vincristine sulfate. A case report.

A patient suffering from Hodgkin's disease exhibiting acute allergic reaction to vincristine sulfate with mild to moderate dermatologic and cardiovascular signs is described. The change of therapy to vindesine sulfate led to relief of all symptoms. The therapeutic effectiveness of the altered protocol remained unchanged and no other or amplified side effects appeared.

Adult↗

Alpha 2-plasmin inhibitor inactivation by human granulocyte elastase.

Plasminogen-binding human alpha 2-plasmin inhibitor is converted by human granulocyte elastase into its non-plasminogen-binding and finally into the inactive form of the inhibitor. This degradation of the plasmin inhibitor, described earlier as "spontaneously" occurring conversion, is shown in dodecyl sulfate polyacrylamide gel electrophoresis, in two-dimensional immunoelectrophoresis and by measuring the kinetics of plasmin inhibition. Experiments in the presence of normal human plasma required unphysiologically high concentrations of elastase to inactivate alpha 2-plasmin inhibitor, suggesting a role of elastase in this type of indirect fibrinolysis in a microenvironment only and not in systemic events.

Electrophoresis, Polyacrylamide Gel↗

Cytochemical determination of granulocyte elastase and chymotrypsin in human myeloid cells and its application in acquired deficiency states and diagnosis of myeloid leukemia.

Two cytochemical methods for detection of granulocytic elastase and chymotrypsin employing alanine and phenylalanine naphthyl esters were developed. Specificity of reaction with the ester substrates was proven by chloromethyl ketone inhibitors. The results of both staining methods were almost identical with the staining for naphthol AS-D chloroacetate (Cl Ac-O Nap AS-D) esterase, since Cl Ac-O Nap AS-D also reacts with granulocyte elastase and chymotrypsin. Mature neutrophils and myeloid precursors except myeloblasts are stained with all three substrates in peripheral blood and bone marrow. Mast cells, however, only react with Cl Ac-O Nap AS-D and the chymotrypsin substrate and not with the elastase substrate. In acute myeloid leukemia the three esterases appear in parallel at a somewhat later stage of maturation than myeloperoxidase. In blood smears from 380 hospital patients no hereditary elastase or chymotrypsin deficiency could be demonstrated. Staining for elastase and chymotrypsin was also normal in hereditary myeloperoxidase deficiency and chronic granulomatous disease. On the other hand 6% of the hospital patients and about two-thirds of patients with acute myeloid leukemia showed a partial elastase deficiency in more than 25% of the peripheral neutrophils.

Chymotrypsin↗

Fibronectin and factor VIII-related antigen in acute leukaemia.

The glycoprotein fibronectin is, as well as by various other cells, also produced in leucocytes and is said to play an important role in malignant transformation of cells. Therefore, the behaviour of plasma fibronectin and of factor VIII R:AG was investigated in acute leukaemia in order to prove their significance as prognostic and therapeutic markers (method: electroimmunoassay). In patients with acute myeloid leukaemia (n = 29) and acute lymphoblastic leukaemia (n = 11) no significant changes in fibronectin concentration could be evaluated. Fibronectin levels declined significantly only during therapy with asparaginase in patients with acute lymphoblastic leukaemia, probably as a result of disturbed synthesis in the liver. Using crossed immunoelectrophoresis against fibronectin antiserum, one normal and one slower migrating antigen (FN:C) could be observed in nearly all plasma samples in patients with acute leukaemia. By means of in vitro tests with highly purified substances and intermediate gel electrophoresis it could be shown that FN:C represents fibronectin which has bound fibrinogen, probably crosslinked by activated factor XIII. Factor VIII R:AG was found to be greatly raised in patients with acute leukaemia--up to 1400% of the normal level. Increased levels correlated well with a worsening of the disease. The protein seems to be suitable for estimating the activity and prognosis of acute leukaemia.

Antigens↗

Immunochemical discrimination of leukocyte elastase from plasmic degradation products of fibrinogen.

A rabbit antiserum was elicited to the D-like fragment (De) generated by cleavage of human fibrinogen with isolated leukocyte elastase. After absorption with intact fibrinogen and plasmic degradation products, the antiserum retained its capacity to recognize the De fragment in radioimmunoassays. Plasmic digests of fibrinogen, produced at various enzyme-to-substrate ratios, and purified plasmic degradation products of fibrinogen reacted poorly with the absorbed antiserum. In contrast, elastase digests of fibrinogen and purified elastase degradation products reacted well, although earlier derivatives expressed the recognized epitopes less well than the De fragment. These observations indicated the recognition of an elastase-elicited neoantigen that was not expressed by plasmic degradation products of fibrinogen. When elastase degradation products were added to normal plasma, the elastase-elicited neoantigen could be quantitatively detected in radioimmunoassay. Normal plasma was negative (less than or equal to 5 nM) for the elastase-elicited neoantigen. Of 30 pathological plasmas containing high concentrations of leukocyte elastase, four contained low levels of the elastase-elicited neoantigen (greater than 15 nM). These results suggest that under most circumstances the fibrinolytic activity of leukocyte elastase is well regulated but that under certain pathophysiological conditions, the leukocyte protease may participate in the fibrinolytic process.

Antibody Specificity↗

Degradation of human plasma fibrin stabilizing factor XIII subunits by human granulocytic proteinases.

Decreased activity of fibrin stabilizing factor XIII may occur in diseases with enhanced destruction of granulocytes. Haemorrhage and impaired wound healing may result. It has been shown by means of SDS-polyacrylamide gel electrophoresis that the neutral proteinases from human polymorphonuclear granulocytes, the Elastase Like Proteinase (ELP), and the Chymotrypsin Like Proteinase (CLP), are able to digest purified human plasma factor XIII. Both subunits, a and b, are affected at concentrations which might locally or systemically occur under pathophysiological conditions. Higher concentrations are required for the degradation of subunit b. Depending on the proteinases, the concentration used and the time of incubation, numerous split products were formed. To obtain comparable effects, the concentration of CLP had to be about twice that of ELP. Aprotinin had only a slight inhibitory effect on the two leukocyte proteinases. The results presented indicate that factor XIII is degraded and inactivated by granulocytic proteinases, both subunits being altered by these proteinases. Therefore the determination of subunit b may be helpful in differentiating between the proteolytic effect of thrombin which degrades only subunit a, and the granulocyte proteinases.

Aprotinin↗

Ectopically produced calcitonin in human hemoblastoses.

The incidence of elevated serum levels of immunoreactive calcitonin (CT) in human myeloproliferative and lymphoproliferative disorders was investigated. On the basis of twice the normal range, about 45% of patients with acute leukemia and blast crisis of chronic myelocytic leukemia (CML) showed elevated serum levels of CT. Markedly elevated levels (greater than 1,000 pg/ml) were only found in this group. Since immunoreactive CT dropped to normal or only slightly elevated levels in remission and increased again before or during relapse, serum CT levels seem to reflect the activity of the disease. However, in patients with chronic leukemia, Hodgkin's and non-Hodgkin's lymphoma, a lower incidence and only slightly elevated serum levels were found. In addition, the molecular weight of the proteohormone in serum specimen and cell extracts was investigated by gel chromatography. Besides physiological CT, different high-molecular weight forms of the hormone could be demonstrated in serum and in cell extracts. Extracts of leukemic cells revealed higher molecular forms only. It is suggested that the proteohormone is ectopically produced by leukemic cells.

Calcitonin↗

[Antidiuretic hormone in patients with bronchial carcinoma (author's transl)].

Antidiuretic hormone (ADH) was determined by radioimmunoassay in 139 patients with bronchial carcinoma. Serum ADH levels, compared with a control group, were increased in 30% of patients with small-cell and 21% of patients with large-cell bronchial carcinoma. Patients with squamous carcinoma or adenocarcinoma had normal ADH values. There was no correlation between serum ADH levels and stage of tumour. Serial ADH measurements during chemotherapy provided good correlation between ADH and response to treatment. ADH was also demonstrable by immunohistology in the tumour cells of one patient with increased serum levels.

Adenocarcinoma↗