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Biomedical subjects

G Krieger

Publications and source records attributed to G Krieger.

At least 37 records · Page 2Linked to original sources

The growth capacity of hematopoietic progenitor cells in severe neutropenia induced by famotidine.

In four cases of severe neutropenia of unknown origin we found a strong inhibition of the growth of granulocyte-macrophage (GM) progenitor cells. The development of GM colonies in culture (GM-CFU-c) was more than 80% reduced in comparison to the control group. In particular, the interleukin 3-(IL-3) and granulocyte macrophage colony-stimulating factor-(GM-CSF) dependent growth was affected; a combination of growth factors (IL-3, GM-CSF, and G-CSF, the granulocyte colony-stimulating factor) resulted in a less reduced growth. The findings were primarily compatible with drug-induced bone marrow failure. Among the medications given to the patients, famotidine, an H2-receptor blocker, was discussed as an agent which possibly triggers off this process. After the withdrawal of famotidine, in three cases a continual increase of the growth of GM precursors was detected, reaching the normal level 7-17 days later. In one case, further investigations of the progenitor cells could not be carried out due to the death of the patient, but the rapid increase of neutrophils in the peripheral blood after withdrawal of famotidine pointed to the recovery of hematopoiesis. In vitro studies showed that famotidine, depending on the dose, inhibits the single growth factor-dependent colony growth (IL-3, GM-CSF, or G-CSF) of bone marrow progenitors from a concentration as low as 10 micrograms/ml. With the combination of all three growth factors only slight inhibitory effects were detectable (up to 150 micrograms/ml famotidine). These results indicate that famotidine, in common with other H2-receptor antagonists, can affect hematopoietic progenitor cells. However, the plasma concentration of famotidine normally used in ulcer therapy does not seem to influence the hematopoiesis. Apparently, the progenitor cells of only a few patients possess a higher sensitivity to the blockade of H2-receptors at this concentration of famotidine. This was demonstrated in one case (patient 3) 2 years after the patient had recovered from famotidine-induced neutropenia. The growth of peripheral myeloid, erythroid, and multilineage progenitor cells of this patient was remarkably reduced even at famotidine concentrations of 0.1-5.0 micron/ml whereas in the control group no inhibition was detected at these famotidine concentrations. Again, the IL-3-dependent colony formation was more affected than in the case of the combination of IL-3, GM-CSF, and G-CSF. After the removal of accessory cells the inhibitory effect of famotidine persisted, demonstrating that accessory cells do not play a major role in this process.

Adult↗

Frequency and structure of t(14;18) major breakpoint regions in non-Hodgkin's lymphomas typed according to the Kiel classification: analysis by direct DNA sequencing.

We have examined 165 unselected cases of non-Hodgkin's lymphomas for rearrangements involving the t(14;18) major breakpoint region using a polymerase chain reaction (PCR) and direct sequencing of amplified major breakpoint region bcl-2/JH junctional regions. The lymphomas, diagnosed according to the updated Kiel classification, consisted of 33 centroblastic-centrocytic, 37 centroblastic, 27 immunocytic, 10 immunoblastic, 10 centrocytic, 2 lymphoblastic, 2 Ki-1-positive anaplastic large cell, 14 peripheral T-cell, and 4 unclassified lymphomas. In addition 18 chronic lymphocytic leukemias, 2 hairy cell leukemias, and 6 plasmacytomas were studied. In 17 cases a bcl-2/JH gene fusion sequence was amplified by PCR. A bcl-2/JH gene fusion was detected only in three lymphoma subgroups: 13 of 33 centroblastic-centrocytic (39%), 2 of 37 centroblastic (6%), and 2 of 27 immunocytic (8%) were positive. In two cases, major breakpoint region bcl-2 rearrangements verified by genomic Southern analysis were not detected by PCR. Direct sequencing of all 17 PCR-amplified, previously uncharacterized t(14;18) junctional regions provided corroborating evidence for the specificity of the assay. The procedure gave sequencing results even from limited amounts of lymphoma cells as obtained by fine needle aspiration of lymph nodes or from clinically uninvolved sites. Clone-specific sequences were identified due to the involvement of different JH segments, the variations among the exact JH and bcl-2 breakpoint positions, and the extensive incorporation of junctional region (D-) N-nucleotides. These clone-specific sequences allow accurate identification of clinically occult lymphoma cells and reduce the threat of false positive results. The finding of exceptionally long intervening sequences in some of the junctions and the partial homology with published DH segments in three cases support the view that some of the putative N-regions harbor DH regions.

Antigens, CD↗

Clinical characteristics of high-grade lymphomas with immune genes in germline configuration.

In a prospective study of 42 high-grade lymphomas which were categorized according to the Kiel classification, the clinical significance of immune genotyping was studied. Immunoglobulin (Ig) and T-cell receptor (TCR) gene rearrangements were investigated. In 33 cases the immune genotype confirmed the phenotype. In one case with equivocal phenotype a TCR beta-chain rearrangement proved the T-cell origin of the lymphoma. None of the cases showed a bigenotype. There were eight lymphomas with immunoglobulin and TCR beta-chain and gamma-chain genes in germline configuration, which were divided into a group of immature lymphomas and a group of lymphomas with a more mature phenotype. The immature lymphomas had widespread disease, rapid progression, and favorable prognosis after intensive chemotherapy. The group of T-cell and Ki-1 lymphomas with null-cell genotype was clinically heterogeneous. Three of four cases were secondary lymphomas after lymphomatoid papulosis, lymphomatoid granulomatosis, or Hodgkin's disease. All cases presented with extranodal involvement. Only one of these patients is in continuous remission. In conclusion, the lack of immunoglobulin and TCR beta-chain and gamma-chain gene rearrangements does not exclude the diagnosis of high-grade malignant lymphoma, especially in cases with unusual extranodal involvement. However, the DNA analysis identifies a null-cell genotype subset of high-grade lymphomas which may have clinical significance.

Adolescent↗

Heterogeneity of immunoglobulin gene rearrangements in B-cell lymphomas.

We have examined 69 B-cell non-Hodgkin's lymphomas (NHL) for rearrangements of the immunoglobulin (Ig) or T-cell antigen receptor (TCR) genes. The lymphomas were assigned to the categories of the Kiel classification and their B-cell nature was confirmed by immunostaining. Only 2 cases (with CLL) displayed clonal T beta-chain TCR gene rearrangements together with rearranged heavy- and light-chain Ig genes. The remaining 67 lymphomas had a germline beta-chain TCR-gene configuration. Three different patterns of Ig gene rearrangements were identified; (A) presence of both heavy- and light-chain rearrangements (H+L+); (B) rearrangement of heavy-chain gene only (H+L-); (C) heavy- and light-chain genes in germline configuration (H-L-). All the 45 low-grade NHLs and the 4 immunoblastic lymphomas exhibited pattern A and all had their kappa gene rearranged or deleted. Of 24 low-grade lymphomas tested, 13 (54%) had an addition rearrangement of the lambda light-chain gene. In contrast, the 19 high-grade centroblastic (cb) B-NHLs had distinct patterns of Ig-gene rearrangement: 12 with pattern A, 4 with B and 2 with C. In this group only 2 of 17 (12%) cases analyzed had evidence of lambda light-chain rearrangement whereas 12 of 18 (67%) had a kappa gene rearrangement or deletion. In one case expressing sIgM/lambda and with heavy chain Ig-rearrangement, no DNA was available for Ig light-chain analysis.

Adolescent↗

Sequence analysis of amplified t(14;18) chromosomal breakpoints in B-cell lymphomas.

We have explored different strategies for sequencing of major breakpoint (mbr) junctional regions in t(14;18) chromosomal translocations--the most frequent chromosomal abnormality observed in B-cell lymphomas. We demonstrate that coupling of the preparation of single-stranded DNA by asymmetric polymerase chain reaction (PCR) and direct sequencing is the method of choice for the rapid and precise determination of clone-specific bcl-2/JH fusion gene sequences. The rapidity, relative ease, and accuracy of the technique, described for the nucleotide sequence analysis of mbr t(14;18) breakpoints, permits the analysis of a relatively large number of samples and should be considered as part of the clinical evaluation of lymphoma patients. Furthermore, by providing sequence information of clone-specific DNA regions, the procedure should reduce the risk of false-positive results from PCR.

Base Sequence↗

[Mucin-like carcinoma-associated antigen: sensitivity and specificity in metastatic breast cancer].

The clinical usefulness of a tumor marker essentially depends on its sensitivity and specificity for a certain tumor. To prove, wheather the new tumor marker 'mucin-like carcinoma-associated antigen' could be used for the management of breast cancer patients, we determined its serum concentration in 50 healthy blood donors, 130 patients with various non-malignant diseases, 138 patients with different metastazised tumors and 137 breast cancer patients. 78 of the breast cancer patients had known metastases while 59 had no evidence of disease after initial surgical and adjuvant therapy. Only 2% of the blood donors and 3% of the patients with non-malignant diseases exceeded the cut-off level of 15 U/ml. In contrast to these findings, 28% of patients with various metastazised tumors and 77% of patients with metastazised breast cancer had serum levels above 15 U/ml. Breast cancer patients without evidence of disease had elevated marker values in only 3%. In breast cancer the serum levels of this antigen depends on the type of metastases. Maximal concentrations were found in mixed metastases while cutaneous or lymph-node metastases showed the lowest rate of positivity. Furthermore a good correlation of serial determined marker levels with the course of the disease was observed, so that we conclude, that mucin-like carcinoma-associated antigen can be used in follow-up of patients with metastazised breast cancer. Because of its high sensitivity and specificity it provides some advantage over other markers used in this disease.

Antigens, Neoplasm↗

[Epstein-Barr virus and malignant lymphomas--studies on incidence and localization of viral DNA].

Tissue specimens from 198 cases of Hodgkin's disease and 151 non-Hodgkin lymphomas as well as 34 non-malignant lymph node biopsies were examined for the presence of Epstein-Barr virus (EBV) DNA by polymerase chain reaction. EBV-specific DNA sequences were detected in DNA extracts of 58% of Hodgkin's disease biopsies. Non-Hodgkin lymphomas and benign lymph node lesions were associated with EBV in far smaller proportions. In Hodgkin's disease biopsies, subsequent in situ hybridization revealed an exclusive localization of EBV DNA in the tumour cells, suggesting an involvement of EBV in the pathogenesis of Hodgkin's disease in a substantial proportion of cases.

Base Sequence↗

High incidence of Epstein-Barr virus genomes in Hodgkin's disease.

Tissue specimens from 198 cases of Hodgkin's disease and 151 non-Hodgkin lymphomas, as well as 34 nonmalignant lymph node biopsies were examined for the presence of Epstein-Barr virus (EBV) DNA by polymerase chain reaction. Epstein-Barr virus-specific DNA sequences were detected in DNA extracts from frozen and/or paraffin-embedded tissues of 58% of Hodgkin's disease cases. High and low grade non-Hodgkin lymphomas as well as chronic lymphocytic leukemia biopsies contained EBV DNA in 26%, 14%, and 7% of the cases, respectively. Ten percent of the control lymph nodes with normal histology were EBV positive. In Hodgkin's disease biopsies, subsequent in situ hybridization revealed an exclusive localization of the viral DNA in the tumor cells. These findings suggest an involvement of EBV in the pathogenesis of Hodgkin's disease in a substantial proportion of cases.

Base Sequence↗

[Balloon catheter arterial occlusion before high-risk splenectomy and nephrectomy].

Balloon catheter occlusion of the splenic or renal artery was undertaken in 10 patients (7 men and 3 women, aged 20-76 years) 30 to 120 min before a splenectomy (n = 8) or nephrectomy (n = 2), for the purpose of preventing a high intra- and post-operative blood loss and facilitating the technical procedure of removing an often markedly enlarged spleen. The operation time after balloon catheter occlusion was only 60-140 min; intra- and post-operative complications did not occur, other than one instance of pneumonia and one of subcutaneous haematoma. This method would seem to be suitable for reducing the operative risk of splenectomy or nephrectomy in the presence of a giant spleen or reduced tolerance of operation.

Adult↗

[Chronic granulocytopenia as a main symptom of T gamma-lymphocytosis].

Routine examination of a 60-year-old woman with long-lasting rheumatic complaints revealed a granulocytopenia in the differential blood count (1% stab cells, 3% segmented) with a normal total leucocyte count (4,200/microliters). It was caused by a lymphoproliferative disease of the granular lymphocytes, which may also be termed T gamma lymphocytosis because of the predominant phenotype. As the lymphocytosis in blood and bone marrow was of minor degree, the diagnosis was confirmed only by immunocytochemical and molecular-genetic demonstration of clonal expansion of the T gamma lymphocytes. The granulocytopenia gradually became more marked and recurrent infections were noted. Treatment with cyclosporin and cortisone brought about remission of the granulocytopenia.

Agranulocytosis↗

[Vaginal tumor--an initial manifestation of malignant histiocytosis].

An anaplastic vaginal tumour was diagnosed in a 29-year-old woman. Before the planned operation leukocytosis and thrombocytopenia developed and further diagnostic tests revealed malignant histiocytosis with bone-marrow infiltration, leukaemic wash-out and tumour formation in the lower pelvis. Intensive chemotherapy, as for acute myeloid leukaemia, achieved full remission. The case demonstrates that, although rare, tumorous organ infiltration may be the initial manifestation of malignant histiocytosis. Its early diagnosis and treatment decisively affects the prognosis.

Adult↗

Characterization of immune complexes detected by the 125I-C1q binding assay in breast cancer.

The aim of the present study was to isolate and characterize immune complexes measured by the 125I-C1q binding assay in breast cancer sera. The C1q binding assay detects immune complexes by their binding to 125I-C1q and subsequent precipitation with PEG. We purified the C1q binding material from these precipitates by superose 6 gel filtration and cation exchange chromatography. The isolation steps were monitored by the C1q binding assay and the purified material was analyzed by SDS--PAGE and immunodiffusion. The C1q binding material isolated from two breast cancer sera contained complexes of IgM, C4b binding protein (C4-bp), and C1q. The C4-bp fraction showed significant C1q binding activity which increased after the addition of IgM. This C4-bp was not different from C4-bp isolated from normal serum. The IgM fraction, however, differed from normal IgM by its binding to C4-bp and C1q and its stronger affinity to the cation exchange column. These unique properties were not due to rheumatoid factor activity. They might be caused by a different glycosylation pattern or by complex formation with an as yet unknown polysaccharide antigen.

Antibodies, Neoplasm↗

[Diagnostic validity of CEA determination in metastasizing breast cancer].

The diagnostic validity of serial CEA determinations in metastatic breast cancer was investigated. First, the CEA values within 8 weeks after start of therapy were correlated with the response to therapy. Second, the CEA levels were used to predict progression after remission or stable disease. These investigations were performed in 150 patients with advanced breast cancer who had clinical follow-ups and serial CEA determinations every one to three months. CEA was not useful for monitoring response to therapy (sensitivity 63%, specifity 58%) or prediction of relapse (sensitivity 61%, specifity 82%) if CEA levels were correlated with clinical course in all patients. However, diagnostic validity of CEA was achieved if the patients were selected and appropriate definitions of significant changes in CEA used. Thus, 83% of the responders (sensitivity) could be identified by a significant decrease of CEA titers in patients with CEA levels of greater than or equal to 10 ng/ml. A decrease of more than 10% of pretreatment levels during the first 4-8 weeks after start of therapy proved to be the appropriate definition of a significant decrease of CEA titers. However, 32% of the nonresponders were misclassified as responders (unspecifity) using these criteria. The positive predictive value of a significant decrease of CEA for response to therapy was 72% (prevalence 45%), the negative predictive value 82% (prevalence 55%). Rising CEA titers specifically predicted progression of disease in patients with remission or stable disease. However, an appropriate sensitivity (86%) was achieved only in patients with baseline CEA levels of greater than or equal to 5 ng/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Antineoplastic Combined Chemotherapy Protocols↗