Search PubMed⌕ Search

Biomedical subjects

D Huhn

Publications and source records attributed to D Huhn.

At least 199 records · Page 11Linked to original sources
PubMed1989

Immunocytochemical detection of p21ras expression in fresh human leukaemic cells and cell lines.

The expression of p21ras proteins was investigated by immunocytochemistry in permanent cell lines and in fresh human leukaemic cells. While high and low levels of p21ras could be detected in most of the cell lines, no significant p21ras immunoreactivity was noted in cells of ten human acute and chronic leukaemias. Thus, notwithstanding its possible role in the initial transformation process in human leukaemias, p21ras expression appears not to be an irrevocable requirement for the maintenance of the transformed state.

Antibodies, Monoclonal↗
PubMed1989

Accidental overdose of mitoxantrone in three patients.

Mitoxantrone is a new effective antineoplastic agent with activity against a wide range of tumors. Compared with the anthracycline drugs doxo- and daunorubicin, it exhibits a clearly lower toxicity and, most importantly, a reduced cardiotoxicity. The analysis of the side-effects recorded after accidental overdosage of the drug gives additional insight into its tolerability. Here we describe our observations in three patients who inadvertently received 100 mg m-2 (two pts) and 183 mg m-2 (one pt) as single slow bolus injections. The main side-effects were moderate nausea and vomiting, shaking chills, and profound but reversible neutro- and thrombocytopenia. There was no immediate cardiac toxicity. One patient with extensive previous daunomycin exposure developed congestive heart failure after 4 months. Two patients were not evaluable for late cardiac complications because of early death due to tumor progression.

Adult↗
PubMed1989

A flow cytometric assay for the determination of cell proliferation with a monoclonal antibody directed against DNA-methyltransferase.

The enzyme DNA-methyltransferase is responsible for the methylation of a newly synthesized DNA-strand. A monoclonal antibody directed against DNA-methyltransferase was used to determine cell proliferation by means of flow cytometry. The reactivity of DNA-methyltransferase antibody was compared with the known proliferation markers transferrin-receptor and Ki67. All three methods showed comparable reactivity with the erythroblastic cell line K562 (86%, 81%, 76% respectively). In a second set of experiments peripheral blood mononuclear cells were stimulated with phytohaemagglutinin; in three experiments, a mean of 63% of the cells reacted with DNA-methyltransferase antibody after 72 h of culture as compared to a mean of 6% in the case of unstimulated control cells. HL60 cells were incubated with DMSO and harvested on day 5 of culture. The results obtained show that in differentiated cells the fraction positive with DNA-methyltransferase antibody decreased to levels below 10%. It is concluded that the technique described is a fast and easy method for the flow cytometric determination of cellular proliferation.

Antibodies, Monoclonal↗
PubMed1989

[Risk-adapted therapy of highly malignant non-Hodgkin's lymphomas with COP-BLAM/IMVP-16: a prospective multicenter study].

In a prospective multicenter therapy trial the remission-inducing potential of the COP-BLAM (5 courses) and the possibly not cross-resistant IMVP-16 (2 courses) regimen for advanced diffuse large cell lymphomas were investigated. Inadequately responding patients were switched early after 2-3 courses to the IMVP-16 protocol. Between January 1986 and August 1988 349 previously untreated patients were recruited who fulfilled the entry criteria: age 15-75 (mean 56 years), stage II-IV. A first restaging after 3 courses of chemotherapy was documented for 280 cases, a second restaging following 7 courses of chemotherapy or a final report was available for 221 patients, 130 of which where in CR (59%). These figures include 29 cases who died already during induction-chemotherapy of progressive disease (n = 17) as well as of therapy-related complications in CR (n = 12). Thirty-three patients were switched early to IMVP-16 due to incomplete response at the first restaging; 13 of those achieved CR by the new regimen (39%), 9 achieved a partial remission which was turned into CR by additional radiotherapy in 5 cases. Dose reductions and interval prolongations were necessary at increasing rates with subsequent chemotherapy courses (20-50% of the cycles). Relapses have occurred in 32 patients so far (14 early, 18 after stop of treatment). The median survival was 24 months (n = 309 patients). These data show that this treatment strategy is effective in a large unselected group of patients of relatively high age. However, patients showing only delayed response with this protocol probably need more aggressive regimens to obtain durable remissions.

Adolescent↗
PubMed1989

Flow-cytometric determination of intracellular pH, esterase activity and cell volume in human leukemic cell lines following in vitro incubation with cytostatic drugs.

A recently developed flow cytometric assay method using patient tumor cells allows the determination not only of their sensitivity to cytostatic drugs but also of biochemical and biophysical parameters after treatment, such as esterase concentration and intracellular pH of the living cells. DNA-content of the dead cells and cell volume of living and dead cells. The T-cell lines CEM, Molt4, Jurkat, the B-cell lines RPMI1788, Daudi, Raji and the promyelocytic line HL60 were incubated with: cytosine arabinoside (ara-C), L-asparaginase, daunorubicin, vincristine and prednisone for 48 h. Living cells then stained with esterase and pH-dye 1,4-diacetoxy-2,3-dicyanobenzene (ADB) and dead cells with DNA-dye propidium-iodide (PI). The esterase concentration, an index of metabolic activity, decreased in the T-cell lines under the influence of ara-C, daunorubicin and vincristine, whereas in the B-cell lines smaller changes in esterase concentration were observed (P less than 0.001). A decrease in intracellular pH was seen in the ara-C and daunorubicin-incubated cells Molt4, CEM and HL60, whereas in the B-cell lines no significant change in intracellular pH was found. In all lines except Jurkat the cell volume of the surviving cells increased under the influence of certain drugs (primarily ara-C and daunorubicin); B-cell lines showed a greater swelling than T-cell lines (P = 0.001).

Antineoplastic Agents↗
PubMed1989

Immunoelectron microscopic identification of human AA-type amyloid: exploration of various monoclonal AA-antibodies, methods of fixation, embedding and of other parameters for the protein-A gold method.

Using the postembedding protein-A gold technique ten monoclonal antibodies directed against amyloid-A protein (AA) were examined by immunoelectron microscopy to identify amyloid-A (AA) amyloid fibrils in plastic-embedded renal tissue of five patients and two controls. Two monoclonal antibodies (mc1, mc20) specifically labeled these amyloid deposits; two additional ones (mc4, mc13) bound with an intermediate rabbit anti-mouse IgG antiserum. These monoclonal anti-AA antibodies clearly separate amyloid fibrils from morphologically similar fibrils in the vicinity. Employing varying embedding media, fixation techniques, as well as etching and staining protocols, we adapted this method for the immunoelectron microscopic identification of AA-type amyloid fibrils and for the antigenic diagnosis of AA-type amyloid on routinely processed ultrathin sections.

Amyloidosis↗
PubMed1988

HIV-related malignant lymphomas. A clinical and pathological study of 13 cases.

The clinical and laboratory records of 13 patients with HIV-related lymphomas diagnosed between 1983 and 1987 are reviewed. 8 cases were classified as high-grade Non-Hodgkin-lymphomas (NHL), 4 as low-grade NHL (including 2 plasmocytomas), and one as Hodgkin's disease (HD). 11 of the 12 NHL were of the B-cell lineage. The mean patient's age was 39 years. At initial staging evaluation extranodal disease was present in 10 patients, in one of them as primary central nervous system (CNS) lymphoma; 9 patients presented with stage III or stage IV involvement. 9 patients were eligible for multidrug chemotherapy. In 5 cases an initial complete remission (CR) was observed, followed, however, by CNS relapse within a few months in 3 patients. 3 patients did not respond to chemotherapy and died within 4 to 6 weeks. Of the 9 patients treated chemotherapeutically, 5 died within 1 to 5 months, 1 is still alive in CR and 3 are still alive in partial remission (PR).

Acquired Immunodeficiency Syndrome↗
PubMed1988

The value of immunocytochemical staining of lymph node aspirates in diagnostic cytology.

This study investigates the applicability of immunocytochemical techniques towards improving the cytological diagnosis of lymph node disorders. Cytocentrifuge preparations of fine needle aspirates were examined using an indirect immunoperoxidase method and the alkaline phosphatase-antialkaline phosphatase method. 36 reactive lymph nodes were evaluated. 23 patients showed T cell predominance as assessed by the presence of CD3+ cells. 13 patients showed an excess of CD24+ cells over CD3+ cells. In all patients the B cell population showed no light chain class restriction. 48 aspirates from patients with B-non-Hodgkin's lymphoma of low malignancy were investigated. The majority of the cells in each of these cases expressed CD24 and 47 cases were monoclonal with respect to their light chain determinants. In 37/48 cases the antibody OKT9 reacted with less than 15% of cells. 18 aspirates were obtained from patients with B-non-Hodgkin's lymphoma of high malignancy. 17 patients showed light chain class restriction and a high percentage of CD24+ (greater than 80%) and OKT9+ (greater than 40%) cells. 8 malignancies were considered to be of T-cell origin. A low percentage (less than 15%) of Ig+CD24+ cells with a high number of CD3+ and/or CD4+ cells suggests a T-cell lymphoma. The majority of neoplastic cells in peripheral T-cell lymphomas (excluding mycosis fungoides) expressed OKT9 and CD3 expression was found to be variable. In 15 cases of Hodgkin's disease, there were 11 correct cytologic diagnoses. A significant number of BerH2 (CD30)+ cells having the morphology of Sternberg-Reed cells supports this diagnosis. 25 aspirates were obtained from patients with metastatic malignant tumours. Marker studies in eight cases helped in distinguishing metastatic malignant tumours from malignant lymphomas. Our findings indicate that the immunocytochemical technique is applicable to cytological material and that the simplicity of the procedure merits application to routine diagnostic cytology.

Antibodies, Monoclonal↗
PubMed1988

[Multicenter prospective risk-adapted study on the therapy of non-Hodgkin's lymphomas of high malignancy. Use of COP-BLAM/IMVP-16 and randomized adjuvant radiotherapy--study concept and preliminary results].

In a multicenter prospective randomized therapeutic trial in advanced (stage II-IV disease, Ann Arbor classification) high-grade malignant non-Hodgkin's lymphomas (NHL, Kiel classification) a sequential combination of the COP-BLAM (5 cycles) and the IMVP-16 (2 cycles) protocols was employed. Response was first determined after 2-3 cycles. In a response-adapted manner the therapy was immediately switched to IMVP-16 if only a partial remission or no response was obtained as evidenced by the first restaging. The aim of the study is the investigation of the efficiency of this concept to induce stable remissions. In an additional randomized trial, involving all patients reaching complete remissions after chemotherapy (second restaging), the prognostic relevance of adjuvant radiotherapy as compared to therapy-free follow-up is evaluated. Eighty percent of the 191 recruited qualified patients have so far become evaluable. Complete clinical remissions were achieved in 76/148 (51%) of the patients up to the first, in 52/85 (61%) of the patients up to the second restaging. Only in a few cases did the expected toxicity of intensive polychemotherapy reach WHO grade 3-4, including nausea and diarrhea, infections, septic complications, myelotoxicity, and stomatitis. Four of the 29 deaths recorded so far occurred in complete remission due to treatment-related complications, whereas 22/29 (76%) died in progression and 3 of unrelated causes.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1988

Treatment of advanced, progressive epidemic Kaposi's sarcoma (EKS): a phase-II study.

The design of a prospective phase-II study on the treatment of Kaposi's sarcoma (KS) in patients with HIV infection is described. In this study the toxicity and antineoplastic activity of high-dose alpha-interferon (20 x 10(6) U/m2 s.c. daily) will be investigated in patients with advanced and progressive KS. Patients with progressing KS during IFN treatment or with relapsing KS after IFN will be treated with vinblastine (4 mg/m2 i.v., days 1, 8, and 15) and bleomycin (15 mg i.v., days 1 + 8). The study was only recently activated; results are so far not available.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Evidence of cross-reactivity of 'carcinoma-specific' KC4 monoclonal antibody with activated mesothelial cells and phytohemagglutinin-stimulated lymphocytes.

Carcinoma-specific antibodies would be a useful tool in immunocytology of serous effusions. We tested the carcinoma-'specific' monoclonal antibody KC4 with cells obtained from pleural effusions evaluated by thoracoscopy and pleural biopsies. KC4 reacted most strongly with carcinoma cells. However, activated mesothelial cells also expressed this marker strongly. Lymphocytes stimulated with phytohemagglutinin were also stained by KC4. Thus KC4 appears to detect a proliferation antigen rather than a carcinoma-specific antigen.

Antibodies, Monoclonal↗