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H Rieder

Publications and source records attributed to H Rieder.

At least 55 records · Page 3Linked to original sources

dic(9;20): a new recurrent chromosome abnormality in adult acute lymphoblastic leukemia.

Loss of chromosome 20 and rearrangement of the short arm of chromosome 9 were identified by banding analysis of three adult patients with acute lymphoblastic leukemia (ALL). The G-banding pattern suggested an identical deletion of 9p, but, also, an unbalanced translocation with chromosome 20 was taken into consideration. Dual-color chromosome painting with probes for chromosomes 9 and 20 revealed the presence of material from chromosome 20 at the short arm of the abnormal chromosome 9 in all three cases. Centromeric alpha-satellite DNA of both chromosome 9 and chromosome 20 was demonstrated by fluorescence in situ hybridization and indicated the presence of a dicentric chromosome. The hybridization of a YAC clone of the short arm of chromosome 20 proved that the dicentric chromosome contained the short arm of chromosome 20, which had been suspected from the G-banding pattern. Thus, the rearrangement was interpreted as dic(9;20)(p11;q11.?1). Because this was the sole chromosome abnormality in two patients, dic(9;20) may be a primary chromosome aberration in ALL. In one case, a 9q+ chromosome derived from a Philadelphia (Ph) translocation was involved in the formation of the dicentric chromosome. Immunophenotyping revealed CD10+ B-cell precursor ALL in all three cases. Whereas the two patients in whom dic(9;20) was the sole cytogenetically detectable change are in continuous complete remission for 10 and 45 months, respectively, the Ph+ patient relapsed with leukemia and died 8 months after diagnosis.

Adult↗

Twenty-three cases of acute lymphoblastic leukemia with translocation t(4;11)(q21;q23): the implication of additional chromosomal aberrations.

The translocation t(4;11)(q21;q23) is one of the most common specific chromosomal aberrations in acute lymphoblastic leukemia (ALL), occurring in 2% of childhood and in 5-6% of adult cases. Especially in adults, the t(4;11) is associated with a poor prognosis. In order to determine the significance of clonal chromosome aberrations that occur in addition to t(4;11), we studied the karyotypes and clinical courses of 23 patients with acute lymphoblastic leukemia and a translocation t(4;11)(q21;q23). Additional clonal chromosome aberrations were found in ten patients. An isochromosome i(7)(q10) and a trisomy 6 were observed most frequently as secondary anomalies. Clonal evolution was detected in four of six patients analyzed at diagnosis as well as at relapse. With treatment carried out according to modern risk-adapted therapy protocols, no difference in outcome was observed between patients with clonal chromosome aberrations in addition to t(4;11) at diagnosis and those without.

Adolescent↗

The fusion of TEL and ABL in human acute lymphoblastic leukaemia is a rare event.

We have recently identified a common ALL patient which harboured a chromosomal fusion between the TEL gene on chromosome 12 and the ABL gene on chromosome 9. We designed an RT-PCR assay to screen 186 adult ALL and 30 childhood ALL patients for this novel translocation. We were unable to identify any additional cases with a TEL/ABL fusion product.

Adult↗

17p anomalies in lymphoid malignancies: diagnostic and prognostic implications.

Eighteen patients with lymphoid malignancies and abnormalities of the short arm of chromosome 17 were evaluated, in order to analyse whether this anomaly was associated with a particular subgroup of lymphoid malignancies. The patients suffered from acute lymphoblastic leukemia, high-grade non-Hodgkin's lymphoma or plasma cell leukemia. No 17p anomaly was found in any patient with chronic lymphocytic leukemia or low-grade non-Hodgkin's lymphoma. In four cases the aberration of the short arm of chromosome 17 was the sole cytogenetic abnormality, in fourteen patients additional chromosomal aberrations were found. Five out of 18 cases were Burkitt's lymphoma/leukemia showing the typical rearrangement of 8q24. In cases with a karyotype evolution the 17p anomaly was always a late event. Concerning the clinical outcome of the patients with abnormalities of the short arm of chromosome 17 eight of nineteen patients died within 90 days after the diagnosis of the 17p anomaly only three were alive at the last follow up (26 months to 40 months after diagnosis of a 17p aberration). Rearrangements of 17p, especially as secondary cytogenetic events, seem to be associated with a poor clinical outcome in lymphoid malignancies.

Adolescent↗

Pre-pre-B acute lymphoblastic leukemia: high frequency of alternatively spliced ALL1-AF4 transcripts and absence of minimal residual disease during complete remission.

We used the polymerase chain reaction (PCR) to detect ALL1-AF4 rearrangements, the molecular hallmark of t(4;11) in a series of 46 pre-pre-B (CD19+, CD24+, CD10/CD20/cylgM/sIgM-) acute lymphoblastic leukemias (ALL). Eighteen patients (39%) exhibited fusion transcripts including 4 of 12 children and 14 of 34 adults. This genetic defect was associated with hyperleukocytosis (median leukocyte count 176 x 10(9)/L) and expression of myeloid-associated antigens (CDw65+). In contrast, only two patients from a group of 67 common (CD19/CD10+, cylgM/sIgM-) and pre-B ALLs (CD19/cylgM+, CD10 +/-, sIgM-) showed ALL1-AF4 mRNA. All PCR-positive cases showed multiple amplification products representing alternative splicing events. Moreover, reciprocal der (4)-derived AF4-ALL1 transcripts were observed in 65% of the cases analyzed. Eight of the 18 pre-pre-B ALL patients with an ALL1-AF4 recombination are currently in complete continuous remission for up to 54 months (median, 26 months). Twelve remission samples were available from seven cases, and all of them lacked evidence of minimal residual disease. Overall this study documents a similarly high incidence of ALL1-AF4 recombinations in children (infants excluded) and adults with pre-pre-B ALL and demonstrates the decline of the leukemic cell clone below the detection level of PCR in a remarkable proportion of patients under intense treatment protocols.

Adolescent↗

[Can the quality of a modest liver transplantation program compare to international standards? Results in Inselspital Berne].

Today, orthotopic liver transplantation is the treatment of choice for the endstage of various liver diseases, and a 1-year survival rate of over 80% is reported in international surveys. The liver transplant program of the Inselspital is very small compared to international centers and this may raise questions about the results and the justification for such a program. In a 24-month period, 20 liver transplants (including 2 retransplants) have been performed in 18 patients at the Inselspital. 2 patients (11%) died 20 and 268 days respectively after transplantation. 2 patients (11%) had significant morbidity 502 and 529 days respectively after transplantation. After a median follow-up of 11.5 months postoperatively, 14 (80% of all patients) lived an independent life. 9 (50%) were fully reintegrated in the household or in their profession and 5 others (30%) were working part time. We conclude that even a small liver transplant program based only on routine resources can achieve results comparable to international standards.

Adult↗

The human vigilin gene: identification, chromosomal localization and expression pattern.

Chick vigilin cRNA clones were used to isolate the cognate human gene, by screening a pWE15 genomic library. Three independent cosmid clones were isolated and characterized by restriction mapping. The gene was identified by sequencing an internal EcoRI fragment containing two exons homologous to exon 24 and 25 of the chicken vigilin gene and corresponding to nucleotides 1973-2104 of the human HBP-cDNA. The homology between the chicken and human sequences was 77% and 82% at the cDNA level, and 91% and 100% at the amino acid level. In addition, the analyzed intron/exon boundaries were invariantly conserved. The 5' and 3' regions of the human gene were mapped by Southern analysis of the respective clones with synthetic oligonucleotides. The entire vigilin gene spans a region of about 50 kb and has been assigned to chromosome 2q36-q37.2 (FL-pter value of 0.96 +/- 0.03) by fluorescence in situ hybridization to metaphase spreads from normal peripheral blood lymphocytes. The vigilin gene is localized in a chromosomal region comprising a cluster of collagen genes (COLIVA3, COLVIA3) and the locus of the Waardenburg syndrome I. Only one mRNA species of 4.4 kb is transcribed from the human vigilin gene. In accordance with previous observations on chicken mRNA, the expression of the human vigilin mRNA depends on the stage of cytodifferentiation both in vitro and in situ.

Blotting, Northern↗

Detection of HRX-FEL fusion transcripts in pre-pre-B-ALL with and without cytogenetic demonstration of t(4;11).

The t(4;11)(q21;q23) characterizes a distinct clinical entity of childhood and adult acute lymphoblastic leukemia (ALL) with a pre-pre-B-phenotype, monocytoid features, coexpression of CD15 and/or CDw65 and a dismal prognosis. The molecular correlate of the t(4;11) has been identified as a fusion transcript of HRX, a gene on 11q23 with homology to drosophila trithorax gene, and FEL, a serine-proline-rich gene on 4q21 of unknown function. The aim of the current study was to establish a reverse transcription-polymerase chain reaction (RT-PCR) approach for the rapid and sensitive detection of the HRX-FEL fusion transcript associated with the t(4;11). For this purpose, two groups of patients were studied: group A comprised cases with cytogenetically proven t(4;11) including three infant and four adult pre-pre-B-ALL, as well as the two cell lines RS4;11 and MV4;11. Group B consisted of ten adult pre-pre-B-ALL with the identical phenotype, but without cytogenetic confirmation of t(4;11). Using primers complementary to HRX and FEL cDNA sequences 300 to 500 bp 5' and 3' of published breakpoints, respectively, specific amplification products were obtained in all nine cases of group A and in nine of the ten cases of group B. Three different types of fusion transcripts were identified by sequence analysis with HRX breakpoints at nucleotides 4086 and 4218 and FEL breakpoints at nucleotides 1413, 1416, and 1458. These data indicate that RT-PCR allows the detection of HRX-FEL fusion transcripts in the vast majority of cytogenetically proven and immunophenotypically suspected t(4;11) ALL. Hence, this technique may allow identification of a further subset of high risk ALL and may also be useful for the monitoring of minimal residual disease in t(4;11) ALL.

Adult↗

Contribution of sinusoidal endothelial liver cells to liver fibrosis: expression of transforming growth factor-beta 1 receptors and modulation of plasmin-generating enzymes by transforming growth factor-beta 1.

Transforming growth factor-beta 1 is an important cytokine in the pathophysiology of liver fibrosis, stimulating the production of extracellular matrix. Whether this cytokine can also control the degradation of matrix proteins in liver cells has not been investigated. Because plasmin is an important protease for the degradation of matrix glycoproteins, we investigated whether sinusoidal endothelial liver cells could contribute to fibrosing liver disease through the modulation of plasmin-generating enzymes in response to transforming growth factor-beta 1. Sinusoidal endothelial cells from guinea pig liver were investigated in pure monolayer culture. Using 125I-labelled transforming growth factor-beta, we demonstrated high-affinity binding sites on sinusoidal endothelial cells at a density of 9.3 x 10(2) per cell, and a dissociation constant of about 5.5 x 10(-11) mol/L. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the known three classes of membrane receptors for transforming growth factor-beta. Using biosynthetic labeling of proteins with 35S-methionine, immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, we showed that sinusoidal endothelial cells produce and secrete plasminogen activator inhibitor type 1 from the beginning of culture. Treatment of confluent cell cultures for 24 hr with transforming growth factor-beta 1 increased synthesis and release of plasminogen activator inhibitor type 1. The response was almost maximal at a concentration of 1 ng transforming growth factor-beta/ml and paralleled the increased synthesis of fibronectin. On reverse fibrin autography we proved that transforming growth factor-beta 1 stimulated the release of functionally active plasminogen activator inhibitor type 1.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Molecular characteristics of HGF-SF and its role in cell motility and invasion.

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) is a potent mitogen for hepatocytes and other cells, and is thought to play a role in liver regeneration. We have presented structural and functional evidence that human SF and human HGF are identical proteins encoded by a single gene, since (i) no differences could be found by protein sequencing, by cDNA analysis, or by immunological comparison, and (ii) SF acts as a hepatocyte growth factor--i.e., stimulates DNA synthesis of primary hepatocytes and is a morphogen of kidney epithelial cells--whereas HGF exhibits SF activity--i.e., dissociates and induces invasiveness of various epithelial cells. Furthermore, there exists only one gene for human HGF-SF which is located on chromosome 7, bands q11.2-21 (Weidner et al., Proc. Natl. Acad. Sci. USA 88, 7001-7005, 1991). HGF-SF has been found to be the ligand of the c-met receptor tyrosine kinase (Naldini et al., EMBO J. 10, 2867-2878, 1991b). We have recently used transient expression of naturally occurring and in vitro mutagenized cDNAs of HGF-SF in order to delineate the protein domains necessary for biological activity and c-met receptor activation. (i) A single-chain HGF-SF resulting from the destruction of the protease cleavage site between heavy and light chain (Arg494 to Gln) was largely inactive, indicating that proteolytic cleavage is essential for acquisition of the biologically active conformation. (ii) A HGF-SF splice variant encoding a protein with a 5 amino acid deletion in the first kringle domain was as highly active as the wild type molecule. (iii) The separately expressed light chain (with serine protease homology) was inactive in all assays tested. (iv) The separate heavy chain as well as a naturally occurring splice variant consisting of the N-terminus and the first two kringle domains bound the met receptor, stimulated its tyrosine phosphorylation, and induced dissociation of epithelial cells but not mitogenesis. These data indicate that a functional domain in the N-terminal region and/or the first two kringle domains of HGF-SF is sufficient for binding to and activation of the met receptor (Hartmann et al., Proc. Natl. Acad. Sci. USA, in press).

Animals↗

Translocation t(1;22) mimicking t(1;19) in a child with acute lymphoblastic leukemia as revealed by chromosome painting.

The karyotype of a boy with acute lymphoblastic leukemia (ALL) presenting with numerical and structural chromosome aberrations as determined by Giemsa-banding was further investigated using chromosome painting (CP). A translocation t(11;18)(q23;q21) was verified by this approach, and gain of chromosome 21 material due to a structural rearrangement was detected. Moreover, an unbalanced translocation of the long arm of chromosome 1, resembling the well known translocation t(1;19), was demonstrated to involve chromosome 22 instead of chromosome 19. Immunophenotyping of the leukemic blasts led to the diagnosis common ALL (CD19+, CD10+, clg-). Our case indicates that in ALL a translocation t(1;19) may be mimicked by other chromosomal rearrangements, and that CP may efficiently complement conventional cytogenetics in the exact characterization of the involved chromosomes.

Child↗

Antibodies to cathepsin G in Crohn's disease.

Antibodies directed against antigens in human neutrophils have proved to be of great diagnostic value in certain systemic vasculitides. Recent reports have focused the attention on these antigens as targets of antibodies in sera of patients with inflammatory bowel disease. We investigated the sera drawn from 60 patients suffering from biopsy proven Crohn's disease and 15 patients with active ulcerative colitis. Using sensitive enzyme-linked immunosorbent assays with purified antigens and Western blotting the following antibodies could be demonstrated: cathepsin G (cat-G) antibodies IgG 38.3%, IgM 13.3%, IgA 23.3% and antibodies against human leucocyte elastase (HLE) IgG, IgA, IgM 3.3%. Low but significant correlations could be found for cat-G antibodies (IgG) and the van HEES index of activity. 73.9% of the cat-G (IgG) positive patients had colon involvement. In the sera of patients with ulcerative colitis no antibodies to cat-G or HLE were detectable. Only 8.3% of the patients with Crohn's disease had antibodies against proteinase 3 (C-ANCA). Our data indicate that cat-G among other myeloid lysosomal enzymes seems to be an important target antigen of antibodies in sera of patients with Crohn's disease. Cat-G antibodies might be helpful to distinguish Crohn's disease from ulcerative colitis.

Adolescent↗