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C Fonatsch

Publications and source records attributed to C Fonatsch.

At least 127 records · Page 7Linked to original sources
PubMed1992

Regional mapping of the gene for autosomal dominant spinocerebellar ataxia (SCA1) by localizing the closely linked D6S89 locus to 6p24.2----p23.05.

The locus for one subtype of autosomal dominant spinocerebellar ataxias (SCA1) is closely linked (within 1-2 cM) to D6S89, which contains a highly polymorphic dinucleotide repeat sequence. D6S89 has been mapped previously to 6p24----p21.3, between the HLA and F13A1 loci. Mutant cell lines were used to correlate the absence or presence of D6S89 with cytogenetically detectable interstitial 6p deletions. The results allowed us to map D6S89 to the 6p24.2----p23.05 region. The close linkage of SCA1 to D6S89 indicates that this locus is most likely located in the 6p24----p23 segment.

Cell Line, Transformed↗
PubMed1992

Karyotype instability in myelodysplastic syndromes--a specific step in pathogenesis preceding clonal chromosome anomalies.

In a prospective study, 20 (11.6%) out of 172 patients with myelodysplastic syndromes (MDS) and two patients with aplastic anemia showed an increased spontaneous karyotype instability. No clonal chromosomal aberrations were detectable at the time of first examination. In three patients clonal anomalies developed during the course of the disease. In 17 out of 22 cases (77.2%) chromosomes 1, 5 or 7 were involved in nonclonal anomalies. The same chromosomes were frequently affected in patients with clonal abnormalities too. Our data suggest that spontaneous karyotype instability may be specific to a high proportion of cases with MDS and may constitute the source of clonal chromosome anomalies in these disorders.

Adult↗
PubMed1992

Polymerase chain reaction analysis of BCR-ABL sequences in adult Philadelphia chromosome-negative acute lymphoblastic leukemia patients.

The Philadelphia (Ph) translocation is the most common cytogenetic abnormality in adult acute lymphoblastic leukemia (ALL) and is associated with an adverse prognosis. Using polymerase chain reaction (PCR) technology we recently observed a remarkably high incidence (55%) of BCR-ABL rearrangements in adult common ALL patients. In the present study we asked whether a subset of Ph-negative cALL, similarly to Ph-negative chronic myelocytic leukemia (CML) patients, exhibit BCR-ABL transcripts. PCR analysis of 58 adult Ph-negative cALL patients, including 47 cases with a normal karyotype revealed no evidence of chimeric BCR-ABL genes. We conclude that Ph-negative BCR/ABL-positive ALL is very rare entity if existing at all.

Adult↗
PubMed1991

Partial trisomy 1q. A nonrandom primary chromosomal abnormality in myelodysplastic syndromes?

Cytogenetic and clinical data of 11 patients with de novo myelodysplastic syndromes and partial or total trisomy of the long arm of chromosome 1 are presented. In eight of these patients trisomy 1q was the sole karyotypic change and therefore can be classified as a primary chromosome anomaly. A remarkably young median age of 36.5 years was noticed in this patient group.

Adolescent↗
PubMed1991

Evidence for the identity of human scatter factor and human hepatocyte growth factor.

Scatter factor (SF), a secretory protein of fibroblasts, dissociates and increases the motility of epithelial cells and may be involved in cell migration processes during embryogenesis and tumor progression. Hepatocyte growth factor (HGF), a protein isolated from serum of patients with liver failure, is a potent mitogen for hepatocytes and is thought to play a role in liver regeneration. Here we present structural and functional evidence that human SF and human HGF (and also the human lung fibroblast-derived mitogen) are identical proteins encoded by a single gene, since (i) no major difference could be found by protein sequencing, by cDNA analysis, and by immunological comparison and (ii) SF in fact acts as a hepatocyte growth factor--i.e., stimulates DNA synthesis of activity--i.e., dissociates and induces invasiveness of various epithelial cells. The human SF/HGF gene was localized to chromosome bands 7q11.2-21. These results have important consequences for further studies on the involvement of SF/HGF as a modulator of cellular growth and motility in embryonal, malignant, and regenerative processes.

Amino Acid Sequence↗
PubMed1991

Detection of chimeric BCR-ABL genes in acute lymphoblastic leukaemia by the polymerase chain reaction.

Philadelphia chromosome-positive acute lymphoblastic leukaemia (ALL) is most common in adults and is associated with poor prognosis. Since karyotypic identification of the Philadelphia translocation has been hampered by technical difficulties, we used the polymerase chain reaction (PCR) to look for the BCR-ABL rearrangement in stored samples from a selected group of 314 German ALL patients. BCR-ABL transcripts were found in 77 of 179 adults and were restricted to those with B-precursor leukaemias. 55% of adult common ALL patients had BCR-ABL and its presence correlated with poor overall survival and remission duration. Of 135 children with common ALL, 5 (6%) primary cases and 8 (17%) with recurrent neoplasias were PCR-positive. We recommend prospective evaluation of BCR-ABL analysis with PCR in patients with a B-precursor leukaemia.

Adult↗
PubMed1991

Translocation (14; 18) and (8; 22) in three patients with acute leukemia/lymphoma following centrocytic/centroblastic non-Hodgkin's lymphoma.

Three patients with centrocytic/centroblastic lymphoma developed a rapidly fatal leukemic transformation of the disease after a transient remission. At the time of transformation, cytogenetic analysis revealed in all patients abnormal karyotypes with coexistence of t (14; 18) and t (8; 22). Molecular analysis in one patient showed rearrangement of the BCL 2 oncogene and c-myc m-RNA expression. These findings imply that translocation t (14; 18) was present during the first phase of the disease and that acquisition of translocation t (8; 22) was accompanied by leukemic transformation.

Acute Disease↗
PubMed1990

Cytogenetic peculiarities in chronic myelogenous leukemia.

Cytogenetic investigations were performed in 185 patients with chronic myelogenous leukemia (CML) at all stages of the disease; 166 patients were Ph positive-159 (95.8%) of these showing the standard Ph translocation, and 7 (4.2%) variant translocations-17 patients were Ph negative. In 2 patients the cytogenetic analysis was unsuccessful. Additional aberrations were found in 40 (24.1%) of the Ph-positive patients. Nine (52.9%) of the Ph-negative patients showed chromosome anomalies. Besides the well known nonrandom abnormalities (-7, +8, i(17q), +19, +Ph) we found a high frequency of clones with rare or not yet described structural rearrangements--in 14 cases (34.2%) of the Ph-positive patients and in 2 cases (20%) of the Ph-negative patients with other chromosome abnormalities. The clinical significance of these findings is discussed.

Adolescent↗
PubMed1990

Chromosomal in situ hybridization of a Hodgkin's disease-derived cell line (L540) using DNA probes for TCRA, TCRB, MET, and rRNA.

The Hodgkin's lymphoma-derived cell line L540, which exhibits multiple marker chromosomes and a genotype characteristic of T-cell origin, showed expression of MET oncogene. L540 was studied by in situ hybridization for chromosomal rearrangements concerning the regions where genes for TCRA and TCRB chains, for MET oncogene, and for rRNA are located. All four genes were demonstrated to be involved in the formation of marker chromosomes. Especially remarkable was the participation of rDNA-bearing regions in two different translocations.

Cell Line↗
PubMed1990

Karyotype and in vitro-response to GM-CSF. Analysis of bone marrow cultures in leukemia, myelodysplasia and aplastic anemia.

The influence of GM-CSF on bone marrow cultures from 13 patients with aplastic anemia, MDS and acute leukemia was studied in a short-term suspension culture system. In each case combined cytogenetic and proliferation analyses were performed with respect to the question, whether chromosome aberrations play a role in the in vitro response to GM-CSF and in order to search for stimulating effects on malignant cells. The responsiveness was compared of aplastic and myelodysplastic cultures on the one hand and of leukemic cells on the other. Our results show that myelodysplastic and aplastic cells display a tendency for reduced susceptibility to GM-CSF as compared to healthy controls, while in leukemic bone marrow the response to the growth factor was significantly enhanced, indicating a leukemia-specific response pattern. In the majority of leukemias analyzed, the presence of cytogenetically abnormal cells in cultures with excessive response to GM-CSF can be taken as a proof for stimulation of malignant cells. The significance of these findings for pathogenesis and prognosis in aplastic anemia, myelodysplasia and leukemia is discussed.

Adolescent↗
PubMed1990

Analysis of bcr rearrangements in primary (essential) thrombocythaemia.

A clinical and molecular study was performed on 10 patients with the presumptive diagnosis of primary thrombocythaemia (PTH). In all cases conspicuous megakaryocytic proliferation in bone marrow smears was detected in the absence of the Philadelphia chromosome (Ph1), elevated red blood cell mass and evidence for a reactive cause of the thrombocytosis. We analyzed whether rearrangements of the bcr gene occurred in untreated patients. Bcr rearrangements were detected in the bone marrow cells but not in peripheral blood bells of one patient, indicating that this case might be related at the molecular level with Philadelphia chromosome negative CML, in which bcr rearrangements could be demonstrated.

Adult↗
PubMed1990

[Comparison of flow cytometric, static cytometry and tumor cytogenetic investigation results human renal cell carcinomas].

Published data about the frequency of DNA-aneuploidy of renal cell tumours show a great variation. The own study was performed to clarify whether this fact is due to methodological discrepancies or to intratumoural heterogeneity of DNA ploidy. The comparison of DNA ploidy assessed by flow cytometry (fresh and paraffin-embedded tissue) and static cytometry (paraffin-embedded tissue) in equivalent tumour regions showed identical results. 71% of clear cell renal carcinomas showed intratumoural heterogeneity of DNA ploidy. In 55% there was either a combination of diploid and aneuploid stem lines and/or a combination of different aneuploid stem lines ("heterogenous aneuploidy"). The rate of aneuploidy was found to be higher with increasing cytoplasmic eosinophilia of the clear cell renal carcinoma cells. Studies which address the prognostic significance of DNA ploidy of renal carcinomas should specifically investigate on the significance of heterogenous aneuploidy for prognosis.

Aneuploidy↗